## What changes were proposed in this pull request?
This is a step towards merging `SQLContext` and `HiveContext`. A new internal Catalog API was introduced in #10982 and extended in #11069. This patch introduces an implementation of this API using `HiveClient`, an existing interface to Hive. It also extends `HiveClient` with additional calls to Hive that are needed to complete the catalog implementation.
*Where should I start reviewing?* The new catalog introduced is `HiveCatalog`. This class is relatively simple because it just calls `HiveClientImpl`, where most of the new logic is. I would not start with `HiveClient`, `HiveQl`, or `HiveMetastoreCatalog`, which are modified mainly because of a refactor.
*Why is this patch so big?* I had to refactor HiveClient to remove an intermediate representation of databases, tables, partitions etc. After this refactor `CatalogTable` convert directly to and from `HiveTable` (etc.). Otherwise we would have to first convert `CatalogTable` to the intermediate representation and then convert that to HiveTable, which is messy.
The new class hierarchy is as follows:
```
org.apache.spark.sql.catalyst.catalog.Catalog
- org.apache.spark.sql.catalyst.catalog.InMemoryCatalog
- org.apache.spark.sql.hive.HiveCatalog
```
Note that, as of this patch, none of these classes are currently used anywhere yet. This will come in the future before the Spark 2.0 release.
## How was the this patch tested?
All existing unit tests, and HiveCatalogSuite that extends CatalogTestCases.
Author: Andrew Or <andrew@databricks.com>
Author: Reynold Xin <rxin@databricks.com>
Closes#11293 from rxin/hive-catalog.
Quite a few Spark SQL join operators broadcast one side of the join to all nodes. The are a few problems with this:
- This conflates broadcasting (a data exchange) with joining. Data exchanges should be managed by a different operator.
- All these nodes implement their own (duplicate) broadcasting logic.
- Re-use of indices is quite hard.
This PR defines both a ```BroadcastDistribution``` and ```BroadcastPartitioning```, these contain a `BroadcastMode`. The `BroadcastMode` defines the way in which we transform the Array of `InternalRow`'s into an index. We currently support the following `BroadcastMode`'s:
- IdentityBroadcastMode: This broadcasts the rows in their original form.
- HashSetBroadcastMode: This applies a projection to the input rows, deduplicates these rows and broadcasts the resulting `Set`.
- HashedRelationBroadcastMode: This transforms the input rows into a `HashedRelation`, and broadcasts this index.
To match this distribution we implement a ```BroadcastExchange``` operator which will perform the broadcast for us, and have ```EnsureRequirements``` plan this operator. The old Exchange operator has been renamed into ShuffleExchange in order to clearly separate between Shuffled and Broadcasted exchanges. Finally the classes in Exchange.scala have been moved to a dedicated package.
cc rxin davies
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#11083 from hvanhovell/SPARK-13136.
## What changes were proposed in this pull request?
This pull request fixes some minor issues (documentation, test flakiness, test organization) with #11190, which was merged earlier tonight.
## How was the this patch tested?
unit tests.
Author: Reynold Xin <rxin@databricks.com>
Closes#11285 from rxin/subquery.
## What changes were proposed in this pull request?
This patch renames logical.Subquery to logical.SubqueryAlias, which is a more appropriate name for this operator (versus subqueries as expressions).
## How was the this patch tested?
Unit tests.
Author: Reynold Xin <rxin@databricks.com>
Closes#11288 from rxin/SPARK-13420.
This PR introduces several major changes:
1. Replacing `Expression.prettyString` with `Expression.sql`
The `prettyString` method is mostly an internal, developer faced facility for debugging purposes, and shouldn't be exposed to users.
1. Using SQL-like representation as column names for selected fields that are not named expression (back-ticks and double quotes should be removed)
Before, we were using `prettyString` as column names when possible, and sometimes the result column names can be weird. Here are several examples:
Expression | `prettyString` | `sql` | Note
------------------ | -------------- | ---------- | ---------------
`a && b` | `a && b` | `a AND b` |
`a.getField("f")` | `a[f]` | `a.f` | `a` is a struct
1. Adding trait `NonSQLExpression` extending from `Expression` for expressions that don't have a SQL representation (e.g. Scala UDF/UDAF and Java/Scala object expressions used for encoders)
`NonSQLExpression.sql` may return an arbitrary user facing string representation of the expression.
Author: Cheng Lian <lian@databricks.com>
Closes#10757 from liancheng/spark-12799.simplify-expression-string-methods.
```scala
// case 1: missing sort columns are resolvable if join is true
sql("SELECT explode(a) AS val, b FROM data WHERE b < 2 order by val, c")
// case 2: missing sort columns are not resolvable if join is false. Thus, issue an error message in this case
sql("SELECT explode(a) AS val FROM data order by val, c")
```
When sort columns are not in `Generate`, we can resolve them when `join` is equal to `true`. Still trying to add more test cases for the other `UnaryNode` types.
Could you review the changes? davies cloud-fan Thanks!
Author: gatorsmile <gatorsmile@gmail.com>
Closes#11198 from gatorsmile/missingInSort.
Conversion of outer joins, if the predicates in filter conditions can restrict the result sets so that all null-supplying rows are eliminated.
- `full outer` -> `inner` if both sides have such predicates
- `left outer` -> `inner` if the right side has such predicates
- `right outer` -> `inner` if the left side has such predicates
- `full outer` -> `left outer` if only the left side has such predicates
- `full outer` -> `right outer` if only the right side has such predicates
If applicable, this can greatly improve the performance, since outer join is much slower than inner join, full outer join is much slower than left/right outer join.
The original PR is https://github.com/apache/spark/pull/10542
Author: gatorsmile <gatorsmile@gmail.com>
Author: xiaoli <lixiao1983@gmail.com>
Author: Xiao Li <xiaoli@Xiaos-MacBook-Pro.local>
Closes#10567 from gatorsmile/outerJoinEliminationByFilterCond.
This PR adds support for rewriting constraints if there are aliases in the query plan. For e.g., if there is a query of form `SELECT a, a AS b`, any constraints on `a` now also apply to `b`.
JIRA: https://issues.apache.org/jira/browse/SPARK-13091
cc marmbrus
Author: Sameer Agarwal <sameer@databricks.com>
Closes#11144 from sameeragarwal/alias.
JIRA: https://issues.apache.org/jira/browse/SPARK-13384
## What changes were proposed in this pull request?
When we de-duplicate attributes in Analyzer, we create new attributes. However, we don't keep original qualifiers. Some plans will be failed to analysed. We should keep original qualifiers in new attributes.
## How was the this patch tested?
Unit test is added.
Author: Liang-Chi Hsieh <viirya@gmail.com>
Closes#11261 from viirya/keep-attr-qualifiers.
`rand` and `randn` functions with a `seed` argument are commonly used. Based on the common sense, the results of `rand` and `randn` should be deterministic if the `seed` parameter value is provided. For example, in MS SQL Server, it also has a function `rand`. Regarding the parameter `seed`, the description is like: ```Seed is an integer expression (tinyint, smallint, or int) that gives the seed value. If seed is not specified, the SQL Server Database Engine assigns a seed value at random. For a specified seed value, the result returned is always the same.```
Update: the current implementation is unable to generate deterministic results when the partitions are not fixed. This PR documents this issue in the function descriptions.
jkbradley hit an issue and provided an example in the following JIRA: https://issues.apache.org/jira/browse/SPARK-13333
Author: gatorsmile <gatorsmile@gmail.com>
Closes#11232 from gatorsmile/randSeed.
Currently, the columns in projects of Expand that are not used by Aggregate are not pruned, this PR fix that.
Author: Davies Liu <davies@databricks.com>
Closes#11225 from davies/fix_pruning_expand.
Add `LazilyGenerateOrdering` to support generated ordering for `RangePartitioner` of `Exchange` instead of `InterpretedOrdering`.
Author: Takuya UESHIN <ueshin@happy-camper.st>
Closes#10894 from ueshin/issues/SPARK-12976.
Using GroupingSets will generate a wrong result when Aggregate Functions containing GroupBy columns.
This PR is to fix it. Since the code changes are very small. Maybe we also can merge it to 1.6
For example, the following query returns a wrong result:
```scala
sql("select course, sum(earnings) as sum from courseSales group by course, earnings" +
" grouping sets((), (course), (course, earnings))" +
" order by course, sum").show()
```
Before the fix, the results are like
```
[null,null]
[Java,null]
[Java,20000.0]
[Java,30000.0]
[dotNET,null]
[dotNET,5000.0]
[dotNET,10000.0]
[dotNET,48000.0]
```
After the fix, the results become correct:
```
[null,113000.0]
[Java,20000.0]
[Java,30000.0]
[Java,50000.0]
[dotNET,5000.0]
[dotNET,10000.0]
[dotNET,48000.0]
[dotNET,63000.0]
```
UPDATE: This PR also deprecated the external column: GROUPING__ID.
Author: gatorsmile <gatorsmile@gmail.com>
Closes#11100 from gatorsmile/groupingSets.
This patch adds a new optimizer rule for performing limit pushdown. Limits will now be pushed down in two cases:
- If a limit is on top of a `UNION ALL` operator, then a partition-local limit operator will be pushed to each of the union operator's children.
- If a limit is on top of an `OUTER JOIN` then a partition-local limit will be pushed to one side of the join. For `LEFT OUTER` and `RIGHT OUTER` joins, the limit will be pushed to the left and right side, respectively. For `FULL OUTER` join, we will only push limits when at most one of the inputs is already limited: if one input is limited we will push a smaller limit on top of it and if neither input is limited then we will limit the input which is estimated to be larger.
These optimizations were proposed previously by gatorsmile in #10451 and #10454, but those earlier PRs were closed and deferred for later because at that time Spark's physical `Limit` operator would trigger a full shuffle to perform global limits so there was a chance that pushdowns could actually harm performance by causing additional shuffles/stages. In #7334, we split the `Limit` operator into separate `LocalLimit` and `GlobalLimit` operators, so we can now push down only local limits (which don't require extra shuffles). This patch is based on both of gatorsmile's patches, with changes and simplifications due to partition-local-limiting.
When we push down the limit, we still keep the original limit in place, so we need a mechanism to ensure that the optimizer rule doesn't keep pattern-matching once the limit has been pushed down. In order to handle this, this patch adds a `maxRows` method to `SparkPlan` which returns the maximum number of rows that the plan can compute, then defines the pushdown rules to only push limits to children if the children's maxRows are greater than the limit's maxRows. This idea is carried over from #10451; see that patch for additional discussion.
Author: Josh Rosen <joshrosen@databricks.com>
Closes#11121 from JoshRosen/limit-pushdown-2.
The java `Calendar` object is expensive to create. I have a sub query like this `SELECT a, b, c FROM table UV WHERE (datediff(UV.visitDate, '1997-01-01')>=0 AND datediff(UV.visitDate, '2015-01-01')<=0))`
The table stores `visitDate` as String type and has 3 billion records. A `Calendar` object is created every time `DateTimeUtils.stringToDate` is called. By reusing the `Calendar` object, I saw about 20 seconds performance improvement for this stage.
Author: Carson Wang <carson.wang@intel.com>
Closes#11090 from carsonwang/SPARK-13185.
The current implementation of ResolveSortReferences can only push one missing attributes into it's child, it failed to analyze TPCDS Q98, because of there are two missing attributes in that (one from Window, another from Aggregate).
Author: Davies Liu <davies@databricks.com>
Closes#11153 from davies/resolve_sort.
JIRA: https://issues.apache.org/jira/browse/SPARK-13277
There is an ANTLR warning during compilation:
warning(200): org/apache/spark/sql/catalyst/parser/SparkSqlParser.g:938:7:
Decision can match input such as "KW_USING Identifier" using multiple alternatives: 2, 3
As a result, alternative(s) 3 were disabled for that input
This patch is to fix it.
Author: Liang-Chi Hsieh <viirya@gmail.com>
Closes#11168 from viirya/fix-parser-using.
The parser currently parses the following strings without a hitch:
* Table Identifier:
* `a.b.c` should fail, but results in the following table identifier `a.b`
* `table!#` should fail, but results in the following table identifier `table`
* Expression
* `1+2 r+e` should fail, but results in the following expression `1 + 2`
This PR fixes this by adding terminated rules for both expression parsing and table identifier parsing.
cc cloud-fan (we discussed this in https://github.com/apache/spark/pull/10649) jayadevanmurali (this causes your PR https://github.com/apache/spark/pull/11051 to fail)
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#11159 from hvanhovell/SPARK-13276.
Grouping() returns a column is aggregated or not, grouping_id() returns the aggregation levels.
grouping()/grouping_id() could be used with window function, but does not work in having/sort clause, will be fixed by another PR.
The GROUPING__ID/grouping_id() in Hive is wrong (according to docs), we also did it wrongly, this PR change that to match the behavior in most databases (also the docs of Hive).
Author: Davies Liu <davies@databricks.com>
Closes#10677 from davies/grouping.
Some analysis rules generate aliases or auxiliary attribute references with the same name but different expression IDs. For example, `ResolveAggregateFunctions` introduces `havingCondition` and `aggOrder`, and `DistinctAggregationRewriter` introduces `gid`.
This is OK for normal query execution since these attribute references get expression IDs. However, it's troublesome when converting resolved query plans back to SQL query strings since expression IDs are erased.
Here's an example Spark 1.6.0 snippet for illustration:
```scala
sqlContext.range(10).select('id as 'a, 'id as 'b).registerTempTable("t")
sqlContext.sql("SELECT SUM(a) FROM t GROUP BY a, b ORDER BY COUNT(a), COUNT(b)").explain(true)
```
The above code produces the following resolved plan:
```
== Analyzed Logical Plan ==
_c0: bigint
Project [_c0#101L]
+- Sort [aggOrder#102L ASC,aggOrder#103L ASC], true
+- Aggregate [a#47L,b#48L], [(sum(a#47L),mode=Complete,isDistinct=false) AS _c0#101L,(count(a#47L),mode=Complete,isDistinct=false) AS aggOrder#102L,(count(b#48L),mode=Complete,isDistinct=false) AS aggOrder#103L]
+- Subquery t
+- Project [id#46L AS a#47L,id#46L AS b#48L]
+- LogicalRDD [id#46L], MapPartitionsRDD[44] at range at <console>:26
```
Here we can see that both aggregate expressions in `ORDER BY` are extracted into an `Aggregate` operator, and both of them are named `aggOrder` with different expression IDs.
The solution is to automatically add the expression IDs into the attribute name for the Alias and AttributeReferences that are generated by Analyzer in SQL Generation.
In this PR, it also resolves another issue. Users could use the same name as the internally generated names. The duplicate names should not cause name ambiguity. When resolving the column, Catalyst should not pick the column that is internally generated.
Could you review the solution? marmbrus liancheng
I did not set the newly added flag for all the alias and attribute reference generated by Analyzers. Please let me know if I should do it? Thank you!
Author: gatorsmile <gatorsmile@gmail.com>
Closes#11050 from gatorsmile/namingConflicts.
This PR improve the lookup of BytesToBytesMap by:
1. Generate code for calculate the hash code of grouping keys.
2. Do not use MemoryLocation, fetch the baseObject and offset for key and value directly (remove the indirection).
Author: Davies Liu <davies@databricks.com>
Closes#11010 from davies/gen_map.
Adds the benchmark results as comments.
The codegen version is slower than the interpreted version for `simple` case becasue of 3 reasons:
1. codegen version use a more complex hash algorithm than interpreted version, i.e. `Murmur3_x86_32.hashInt` vs [simple multiplication and addition](https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/rows.scala#L153).
2. codegen version will write the hash value to a row first and then read it out. I tried to create a `GenerateHasher` that can generate code to return hash value directly and got about 60% speed up for the `simple` case, does it worth?
3. the row in `simple` case only has one int field, so the runtime reflection may be removed because of branch prediction, which makes the interpreted version faster.
The `array` case is also slow for similar reasons, e.g. array elements are of same type, so interpreted version can probably get rid of runtime reflection by branch prediction.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10917 from cloud-fan/hash-benchmark.
nullability should only be considered as an optimization rather than part of the type system, so instead of failing analysis for mismatch nullability, we should pass analysis and add runtime null check.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#11035 from cloud-fan/ignore-nullability.
This patch changes the implementation of the physical `Limit` operator so that it relies on the `Exchange` operator to perform data movement rather than directly using `ShuffledRDD`. In addition to improving efficiency, this lays the necessary groundwork for further optimization of limit, such as limit pushdown or whole-stage codegen.
At a high-level, this replaces the old physical `Limit` operator with two new operators, `LocalLimit` and `GlobalLimit`. `LocalLimit` performs per-partition limits, while `GlobalLimit` applies the final limit to a single partition; `GlobalLimit`'s declares that its `requiredInputDistribution` is `SinglePartition`, which will cause the planner to use an `Exchange` to perform the appropriate shuffles. Thus, a logical `Limit` appearing in the middle of a query plan will be expanded into `LocalLimit -> Exchange to one partition -> GlobalLimit`.
In the old code, calling `someDataFrame.limit(100).collect()` or `someDataFrame.take(100)` would actually skip the shuffle and use a fast-path which used `executeTake()` in order to avoid computing all partitions in case only a small number of rows were requested. This patch preserves this optimization by treating logical `Limit` operators specially when they appear as the terminal operator in a query plan: if a `Limit` is the final operator, then we will plan a special `CollectLimit` physical operator which implements the old `take()`-based logic.
In order to be able to match on operators only at the root of the query plan, this patch introduces a special `ReturnAnswer` logical operator which functions similar to `BroadcastHint`: this dummy operator is inserted at the root of the optimized logical plan before invoking the physical planner, allowing the planner to pattern-match on it.
Author: Josh Rosen <joshrosen@databricks.com>
Closes#7334 from JoshRosen/remove-copy-in-limit.
Trivial search-and-replace to eliminate deprecation warnings in Scala 2.11.
Also works with 2.10
Author: Jakob Odersky <jakob@odersky.com>
Closes#11085 from jodersky/SPARK-13171.
https://issues.apache.org/jira/browse/SPARK-12939
Now we will catch `ObjectOperator` in `Analyzer` and resolve the `fromRowExpression/deserializer` inside it. Also update the `MapGroups` and `CoGroup` to pass in `dataAttributes`, so that we can correctly resolve value deserializer(the `child.output` contains both groupking key and values, which may mess things up if they have same-name attribtues). End-to-end tests are added.
follow-ups:
* remove encoders from typed aggregate expression.
* completely remove resolve/bind in `ExpressionEncoder`
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10852 from cloud-fan/bug.
This patch incorporates review feedback from #11069, which is already merged.
Author: Andrew Or <andrew@databricks.com>
Closes#11080 from andrewor14/catalog-follow-ups.
Spark SQL should collapse adjacent `Repartition` operators and only keep the last one.
Author: Josh Rosen <joshrosen@databricks.com>
Closes#11064 from JoshRosen/collapse-repartition.
This is a small addendum to #10762 to make the code more robust again future changes.
Author: Reynold Xin <rxin@databricks.com>
Closes#11070 from rxin/SPARK-12828-natural-join.
This is a step towards consolidating `SQLContext` and `HiveContext`.
This patch extends the existing Catalog API added in #10982 to include methods for handling table partitions. In particular, a partition is identified by `PartitionSpec`, which is just a `Map[String, String]`. The Catalog is still not used by anything yet, but its API is now more or less complete and an implementation is fully tested.
About 200 lines are test code.
Author: Andrew Or <andrew@databricks.com>
Closes#11069 from andrewor14/catalog.
The ```SparkSqlLexer``` currently swallows characters which have not been defined in the grammar. This causes problems with SQL commands, such as: ```add jar file:///tmp/ab/TestUDTF.jar```. In this example the `````` is swallowed.
This PR adds an extra Lexer rule to handle such input, and makes a tiny modification to the ```ASTNode```.
cc davies liancheng
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#11052 from hvanhovell/SPARK-13157.
Based on the semantics of a query, we can derive a number of data constraints on output of each (logical or physical) operator. For instance, if a filter defines `‘a > 10`, we know that the output data of this filter satisfies 2 constraints:
1. `‘a > 10`
2. `isNotNull(‘a)`
This PR proposes a possible way of keeping track of these constraints and propagating them in the logical plan, which can then help us build more advanced optimizations (such as pruning redundant filters, optimizing joins, among others). We define constraints as a set of (implicitly conjunctive) expressions. For e.g., if a filter operator has constraints = `Set(‘a > 10, ‘b < 100)`, it’s implied that the outputs satisfy both individual constraints (i.e., `‘a > 10` AND `‘b < 100`).
Design Document: https://docs.google.com/a/databricks.com/document/d/1WQRgDurUBV9Y6CWOBS75PQIqJwT-6WftVa18xzm7nCo/edit?usp=sharing
Author: Sameer Agarwal <sameer@databricks.com>
Closes#10844 from sameeragarwal/constraints.
1. try to avoid the suffix (unique id)
2. remove the comment if there is no code generated.
3. re-arrange the order of functions
4. trop the new line for inlined blocks.
Author: Davies Liu <davies@databricks.com>
Closes#11032 from davies/better_suffix.
when we generate map, we first randomly pick a length, then create a seq of key value pair with the expected length, and finally call `toMap`. However, `toMap` will remove all duplicated keys, which makes the actual map size much less than we expected.
This PR fixes this problem by put keys in a set first, to guarantee we have enough keys to build a map with expected length.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10930 from cloud-fan/random-generator.
The example will throw error like
<console>:20: error: not found: value StructType
Need to add this line:
import org.apache.spark.sql.types._
Author: Kevin (Sangwoo) Kim <sangwookim.me@gmail.com>
Closes#10141 from swkimme/patch-1.
As benchmarked and discussed here: https://github.com/apache/spark/pull/10786/files#r50038294, benefits from codegen, the declarative aggregate function could be much faster than imperative one.
Author: Davies Liu <davies@databricks.com>
Closes#10960 from davies/stddev.
Jira:
https://issues.apache.org/jira/browse/SPARK-13056
Create a map like
{ "a": "somestring", "b": null}
Query like
SELECT col["b"] FROM t1;
NPE would be thrown.
Author: Daoyuan Wang <daoyuan.wang@intel.com>
Closes#10964 from adrian-wang/npewriter.
This pull request creates an internal catalog API. The creation of this API is the first step towards consolidating SQLContext and HiveContext. I envision we will have two different implementations in Spark 2.0: (1) a simple in-memory implementation, and (2) an implementation based on the current HiveClient (ClientWrapper).
I took a look at what Hive's internal metastore interface/implementation, and then created this API based on it. I believe this is the minimal set needed in order to achieve all the needed functionality.
Author: Reynold Xin <rxin@databricks.com>
Closes#10982 from rxin/SPARK-13078.
This includes: float, boolean, short, decimal and calendar interval.
Decimal is mapped to long or byte array depending on the size and calendar
interval is mapped to a struct of int and long.
The only remaining type is map. The schema mapping is straightforward but
we might want to revisit how we deal with this in the rest of the execution
engine.
Author: Nong Li <nong@databricks.com>
Closes#10961 from nongli/spark-13043.
JIRA: https://issues.apache.org/jira/browse/SPARK-12705
**Scope:**
This PR is a general fix for sorting reference resolution when the child's `outputSet` does not have the order-by attributes (called, *missing attributes*):
- UnaryNode support is limited to `Project`, `Window`, `Aggregate`, `Distinct`, `Filter`, `RepartitionByExpression`.
- We will not try to resolve the missing references inside a subquery, unless the outputSet of this subquery contains it.
**General Reference Resolution Rules:**
- Jump over the nodes with the following types: `Distinct`, `Filter`, `RepartitionByExpression`. Do not need to add missing attributes. The reason is their `outputSet` is decided by their `inputSet`, which is the `outputSet` of their children.
- Group-by expressions in `Aggregate`: missing order-by attributes are not allowed to be added into group-by expressions since it will change the query result. Thus, in RDBMS, it is not allowed.
- Aggregate expressions in `Aggregate`: if the group-by expressions in `Aggregate` contains the missing attributes but aggregate expressions do not have it, just add them into the aggregate expressions. This can resolve the analysisExceptions thrown by the three TCPDS queries.
- `Project` and `Window` are special. We just need to add the missing attributes to their `projectList`.
**Implementation:**
1. Traverse the whole tree in a pre-order manner to find all the resolvable missing order-by attributes.
2. Traverse the whole tree in a post-order manner to add the found missing order-by attributes to the node if their `inputSet` contains the attributes.
3. If the origins of the missing order-by attributes are different nodes, each pass only resolves the missing attributes that are from the same node.
**Risk:**
Low. This rule will be trigger iff ```!s.resolved && child.resolved``` is true. Thus, very few cases are affected.
Author: gatorsmile <gatorsmile@gmail.com>
Closes#10678 from gatorsmile/sortWindows.
JIRA: https://issues.apache.org/jira/browse/SPARK-12989
In the rule `ExtractWindowExpressions`, we simply replace alias by the corresponding attribute. However, this will cause an issue exposed by the following case:
```scala
val data = Seq(("a", "b", "c", 3), ("c", "b", "a", 3)).toDF("A", "B", "C", "num")
.withColumn("Data", struct("A", "B", "C"))
.drop("A")
.drop("B")
.drop("C")
val winSpec = Window.partitionBy("Data.A", "Data.B").orderBy($"num".desc)
data.select($"*", max("num").over(winSpec) as "max").explain(true)
```
In this case, both `Data.A` and `Data.B` are `alias` in `WindowSpecDefinition`. If we replace these alias expression by their alias names, we are unable to know what they are since they will not be put in `missingExpr` too.
Author: gatorsmile <gatorsmile@gmail.com>
Author: xiaoli <lixiao1983@gmail.com>
Author: Xiao Li <xiaoli@Xiaos-MacBook-Pro.local>
Closes#10963 from gatorsmile/seletStarAfterColDrop.
The current implementation is sub-optimal:
* If an expression is always nullable, e.g. `Unhex`, we can still remove null check for children if they are not nullable.
* If an expression has some non-nullable children, we can still remove null check for these children and keep null check for others.
This PR improves this by making the null check elimination more fine-grained.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10987 from cloud-fan/null-check.
JIRA: https://issues.apache.org/jira/browse/SPARK-12689
DDLParser processes three commands: createTable, describeTable and refreshTable.
This patch migrates the three commands to newly absorbed parser.
Author: Liang-Chi Hsieh <viirya@gmail.com>
Author: Liang-Chi Hsieh <viirya@appier.com>
Closes#10723 from viirya/migrate-ddl-describe.
Make sure we throw better error messages when Parquet schema merging fails.
Author: Cheng Lian <lian@databricks.com>
Author: Liang-Chi Hsieh <viirya@gmail.com>
Closes#10979 from viirya/schema-merging-failure-message.
In jdk1.7 TimeZone.getTimeZone() is synchronized, so use an instance variable to hold an GMT TimeZone object instead of instantiate it every time.
Author: wangyang <wangyang@haizhi.com>
Closes#10994 from wangyang1992/datetimeUtil.
This patch changes Spark's build to make Scala 2.11 the default Scala version. To be clear, this does not mean that Spark will stop supporting Scala 2.10: users will still be able to compile Spark for Scala 2.10 by following the instructions on the "Building Spark" page; however, it does mean that Scala 2.11 will be the default Scala version used by our CI builds (including pull request builds).
The Scala 2.11 compiler is faster than 2.10, so I think we'll be able to look forward to a slight speedup in our CI builds (it looks like it's about 2X faster for the Maven compile-only builds, for instance).
After this patch is merged, I'll update Jenkins to add new compile-only jobs to ensure that Scala 2.10 compilation doesn't break.
Author: Josh Rosen <joshrosen@databricks.com>
Closes#10608 from JoshRosen/SPARK-6363.
This class is only used for serialization of Python DataFrame. However, we don't require internal row there, so `GenericRowWithSchema` can also do the job.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10992 from cloud-fan/python.
This PR add support for grouping keys for generated TungstenAggregate.
Spilling and performance improvements for BytesToBytesMap will be done by followup PR.
Author: Davies Liu <davies@databricks.com>
Closes#10855 from davies/gen_keys.
Our current Intersect physical operator simply delegates to RDD.intersect. We should remove the Intersect physical operator and simply transform a logical intersect into a semi-join with distinct. This way, we can take advantage of all the benefits of join implementations (e.g. managed memory, code generation, broadcast joins).
After a search, I found one of the mainstream RDBMS did the same. In their query explain, Intersect is replaced by Left-semi Join. Left-semi Join could help outer-join elimination in Optimizer, as shown in the PR: https://github.com/apache/spark/pull/10566
Author: gatorsmile <gatorsmile@gmail.com>
Author: xiaoli <lixiao1983@gmail.com>
Author: Xiao Li <xiaoli@Xiaos-MacBook-Pro.local>
Closes#10630 from gatorsmile/IntersectBySemiJoin.
1. enable whole stage codegen during tests even there is only one operator supports that.
2. split doProduce() into two APIs: upstream() and doProduce()
3. generate prefix for fresh names of each operator
4. pass UnsafeRow to parent directly (avoid getters and create UnsafeRow again)
5. fix bugs and tests.
This PR re-open #10944 and fix the bug.
Author: Davies Liu <davies@databricks.com>
Closes#10977 from davies/gen_refactor.
A simple workaround to avoid getting parameter types when convert a
logical plan to json.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10970 from cloud-fan/reflection.
JIRA: https://issues.apache.org/jira/browse/SPARK-12968
Implement command to set current database.
Author: Liang-Chi Hsieh <viirya@gmail.com>
Author: Liang-Chi Hsieh <viirya@appier.com>
Closes#10916 from viirya/ddl-use-database.
JIRA: https://issues.apache.org/jira/browse/SPARK-11955
Currently we simply skip pushdowning filters in parquet if we enable schema merging.
However, we can actually mark particular fields in merging schema for safely pushdowning filters in parquet.
Author: Liang-Chi Hsieh <viirya@appier.com>
Author: Liang-Chi Hsieh <viirya@gmail.com>
Closes#9940 from viirya/safe-pushdown-parquet-filters.
1. enable whole stage codegen during tests even there is only one operator supports that.
2. split doProduce() into two APIs: upstream() and doProduce()
3. generate prefix for fresh names of each operator
4. pass UnsafeRow to parent directly (avoid getters and create UnsafeRow again)
5. fix bugs and tests.
Author: Davies Liu <davies@databricks.com>
Closes#10944 from davies/gen_refactor.
This PR moves all the functionality provided by the SparkSQLParser/ExtendedHiveQlParser to the new Parser hierarchy (SparkQl/HiveQl). This also improves the current SET command parsing: the current implementation swallows ```set role ...``` and ```set autocommit ...``` commands, this PR respects these commands (and passes them on to Hive).
This PR and https://github.com/apache/spark/pull/10723 end the use of Parser-Combinator parsers for SQL parsing. As a result we can also remove the ```AbstractSQLParser``` in Catalyst.
The PR is marked WIP as long as it doesn't pass all tests.
cc rxin viirya winningsix (this touches https://github.com/apache/spark/pull/10144)
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#10905 from hvanhovell/SPARK-12866.
The error message is now changed from "Do not support type class scala.Tuple2." to "Do not support type class org.json4s.JsonAST$JNull$" to be more informative about what is not supported. Also, StructType metadata now handles JNull correctly, i.e., {'a': None}. test_metadata_null is added to tests.py to show the fix works.
Author: Jason Lee <cjlee@us.ibm.com>
Closes#8969 from jasoncl/SPARK-10847.
This patch adds support for complex types for ColumnarBatch. ColumnarBatch supports structs
and arrays. There is a simple mapping between the richer catalyst types to these two. Strings
are treated as an array of bytes.
ColumnarBatch will contain a column for each node of the schema. Non-complex schemas consists
of just leaf nodes. Structs represent an internal node with one child for each field. Arrays
are internal nodes with one child. Structs just contain nullability. Arrays contain offsets
and lengths into the child array. This structure is able to handle arbitrary nesting. It has
the key property that we maintain columnar throughout and that primitive types are only stored
in the leaf nodes and contiguous across rows. For example, if the schema is
```
array<array<int>>
```
There are three columns in the schema. The internal nodes each have one children. The leaf node contains all the int data stored consecutively.
As part of this, this patch adds append APIs in addition to the Put APIs (e.g. putLong(rowid, v)
vs appendLong(v)). These APIs are necessary when the batch contains variable length elements.
The vectors are not fixed length and will grow as necessary. This should make the usage a lot
simpler for the writer.
Author: Nong Li <nong@databricks.com>
Closes#10820 from nongli/spark-12854.
Otherwise the `^` character is always marked as error in IntelliJ since it represents an unclosed superscript markup tag.
Author: Cheng Lian <lian@databricks.com>
Closes#10926 from liancheng/agg-doc-fix.
As we begin to use unsafe row writing framework(`BufferHolder` and `UnsafeRowWriter`) in more and more places(`UnsafeProjection`, `UnsafeRowParquetRecordReader`, `GenerateColumnAccessor`, etc.), we should add more doc to it and make it easier to use.
This PR abstract the technique used in `UnsafeRowParquetRecordReader`: avoid unnecessary operatition as more as possible. For example, do not always point the row to the buffer at the end, we only need to update the size of row. If all fields are of primitive type, we can even save the row size updating. Then we can apply this technique to more places easily.
a local benchmark shows `UnsafeProjection` is up to 1.7x faster after this PR:
**old version**
```
Intel(R) Core(TM) i7-4960HQ CPU 2.60GHz
unsafe projection: Avg Time(ms) Avg Rate(M/s) Relative Rate
-------------------------------------------------------------------------------
single long 2616.04 102.61 1.00 X
single nullable long 3032.54 88.52 0.86 X
primitive types 9121.05 29.43 0.29 X
nullable primitive types 12410.60 21.63 0.21 X
```
**new version**
```
Intel(R) Core(TM) i7-4960HQ CPU 2.60GHz
unsafe projection: Avg Time(ms) Avg Rate(M/s) Relative Rate
-------------------------------------------------------------------------------
single long 1533.34 175.07 1.00 X
single nullable long 2306.73 116.37 0.66 X
primitive types 8403.93 31.94 0.18 X
nullable primitive types 12448.39 21.56 0.12 X
```
For single non-nullable long(the best case), we can have about 1.7x speed up. Even it's nullable, we can still have 1.3x speed up. For other cases, it's not such a boost as the saved operations only take a little proportion of the whole process. The benchmark code is included in this PR.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10809 from cloud-fan/unsafe-projection.
This pull request implements strength reduction for comparing integral expressions and decimal literals, which is more common now because we switch to parsing fractional literals as decimal types (rather than doubles). I added the rules to the existing DecimalPrecision rule with some refactoring to simplify the control flow. I also moved DecimalPrecision rule into its own file due to the growing size.
Author: Reynold Xin <rxin@databricks.com>
Closes#10882 from rxin/SPARK-12904-1.
The current parser turns a decimal literal, for example ```12.1```, into a Double. The problem with this approach is that we convert an exact literal into a non-exact ```Double```. The PR changes this behavior, a Decimal literal is now converted into an extact ```BigDecimal```.
The behavior for scientific decimals, for example ```12.1e01```, is unchanged. This will be converted into a Double.
This PR replaces the ```BigDecimal``` literal by a ```Double``` literal, because the ```BigDecimal``` is the default now. You can use the double literal by appending a 'D' to the value, for instance: ```3.141527D```
cc davies rxin
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#10796 from hvanhovell/SPARK-12848.
Benchmark it on 4 different schemas, the result:
```
Intel(R) Core(TM) i7-4960HQ CPU 2.60GHz
Hash For simple: Avg Time(ms) Avg Rate(M/s) Relative Rate
-------------------------------------------------------------------------------
interpreted version 31.47 266.54 1.00 X
codegen version 64.52 130.01 0.49 X
```
```
Intel(R) Core(TM) i7-4960HQ CPU 2.60GHz
Hash For normal: Avg Time(ms) Avg Rate(M/s) Relative Rate
-------------------------------------------------------------------------------
interpreted version 4068.11 0.26 1.00 X
codegen version 1175.92 0.89 3.46 X
```
```
Intel(R) Core(TM) i7-4960HQ CPU 2.60GHz
Hash For array: Avg Time(ms) Avg Rate(M/s) Relative Rate
-------------------------------------------------------------------------------
interpreted version 9276.70 0.06 1.00 X
codegen version 14762.23 0.04 0.63 X
```
```
Intel(R) Core(TM) i7-4960HQ CPU 2.60GHz
Hash For map: Avg Time(ms) Avg Rate(M/s) Relative Rate
-------------------------------------------------------------------------------
interpreted version 58869.79 0.01 1.00 X
codegen version 9285.36 0.06 6.34 X
```
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10816 from cloud-fan/hash-benchmark.
The existing `Union` logical operator only supports two children. Thus, adding a new logical operator `Unions` which can have arbitrary number of children to replace the existing one.
`Union` logical plan is a binary node. However, a typical use case for union is to union a very large number of input sources (DataFrames, RDDs, or files). It is not uncommon to union hundreds of thousands of files. In this case, our optimizer can become very slow due to the large number of logical unions. We should change the Union logical plan to support an arbitrary number of children, and add a single rule in the optimizer to collapse all adjacent `Unions` into a single `Unions`. Note that this problem doesn't exist in physical plan, because the physical `Unions` already supports arbitrary number of children.
Author: gatorsmile <gatorsmile@gmail.com>
Author: xiaoli <lixiao1983@gmail.com>
Author: Xiao Li <xiaoli@Xiaos-MacBook-Pro.local>
Closes#10577 from gatorsmile/unionAllMultiChildren.
Also updated documentation to explain why ComputeCurrentTime and EliminateSubQueries are in the optimizer rather than analyzer.
Author: Reynold Xin <rxin@databricks.com>
Closes#10837 from rxin/optimizer-analyzer-comment.
The three optimization cases are:
1. If the first branch's condition is a true literal, remove the CaseWhen and use the value from that branch.
2. If a branch's condition is a false or null literal, remove that branch.
3. If only the else branch is left, remove the CaseWhen and use the value from the else branch.
Author: Reynold Xin <rxin@databricks.com>
Closes#10827 from rxin/SPARK-12770.
Call `dealias` on local types to fix schema generation for abstract type members, such as
```scala
type KeyValue = (Int, String)
```
Add simple test
Author: Jakob Odersky <jodersky@gmail.com>
Closes#10749 from jodersky/aliased-schema.
JIRA: https://issues.apache.org/jira/browse/SPARK-12867
When intersecting one nullable column with one non-nullable column, the result will not contain any null. Thus, we can make nullability of `intersect` stricter.
liancheng Could you please check if the code changes are appropriate? Also added test cases to verify the results. Thanks!
Author: gatorsmile <gatorsmile@gmail.com>
Closes#10812 from gatorsmile/nullabilityIntersect.
Based on discussions in #10801, I'm submitting a pull request to rename ParserDialect to ParserInterface.
Author: Reynold Xin <rxin@databricks.com>
Closes#10817 from rxin/SPARK-12889.
In SPARK-10743 we wrap cast with `UnresolvedAlias` to give `Cast` a better alias if possible. However, for cases like `filter`, the `UnresolvedAlias` can't be resolved and actually we don't need a better alias for this case. This PR move the cast wrapping logic to `Column.named` so that we will only do it when we need a alias name.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10781 from cloud-fan/bug.
This pull request removes the public developer parser API for external parsers. Given everything a parser depends on (e.g. logical plans and expressions) are internal and not stable, external parsers will break with every release of Spark. It is a bad idea to create the illusion that Spark actually supports pluggable parsers. In addition, this also reduces incentives for 3rd party projects to contribute parse improvements back to Spark.
Author: Reynold Xin <rxin@databricks.com>
Closes#10801 from rxin/SPARK-12855.
I was reading this part of the analyzer code again and got confused by the difference between findWiderTypeForTwo and findTightestCommonTypeOfTwo.
I also simplified WidenSetOperationTypes to make it a lot simpler. The easiest way to review this one is to just read the original code, and the new code. The logic is super simple.
Author: Reynold Xin <rxin@databricks.com>
Closes#10802 from rxin/SPARK-12873.
This is the initial work for whole stage codegen, it support Projection/Filter/Range, we will continue work on this to support more physical operators.
A micro benchmark show that a query with range, filter and projection could be 3X faster then before.
It's turned on by default. For a tree that have at least two chained plans, a WholeStageCodegen will be inserted into it, for example, the following plan
```
Limit 10
+- Project [(id#5L + 1) AS (id + 1)#6L]
+- Filter ((id#5L & 1) = 1)
+- Range 0, 1, 4, 10, [id#5L]
```
will be translated into
```
Limit 10
+- WholeStageCodegen
+- Project [(id#1L + 1) AS (id + 1)#2L]
+- Filter ((id#1L & 1) = 1)
+- Range 0, 1, 4, 10, [id#1L]
```
Here is the call graph to generate Java source for A and B (A support codegen, but B does not):
```
* WholeStageCodegen Plan A FakeInput Plan B
* =========================================================================
*
* -> execute()
* |
* doExecute() --------> produce()
* |
* doProduce() -------> produce()
* |
* doProduce() ---> execute()
* |
* consume()
* doConsume() ------------|
* |
* doConsume() <----- consume()
```
A SparkPlan that support codegen need to implement doProduce() and doConsume():
```
def doProduce(ctx: CodegenContext): (RDD[InternalRow], String)
def doConsume(ctx: CodegenContext, child: SparkPlan, input: Seq[ExprCode]): String
```
Author: Davies Liu <davies@databricks.com>
Closes#10735 from davies/whole2.
We iterate the bytes to calculate hashCode before, but now we have `Murmur3_x86_32.hashUnsafeBytes` that don't require the bytes to be word algned, we should use that instead.
A simple benchmark shows it's about 3 X faster, benchmark code: https://gist.github.com/cloud-fan/fa77713ccebf0823b2ab#file-arrayhashbenchmark-scala
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10784 from cloud-fan/array-hashcode.
In this PR the new CatalystQl parser stack reaches grammar parity with the old Parser-Combinator based SQL Parser. This PR also replaces all uses of the old Parser, and removes it from the code base.
Although the existing Hive and SQL parser dialects were mostly the same, some kinks had to be worked out:
- The SQL Parser allowed syntax like ```APPROXIMATE(0.01) COUNT(DISTINCT a)```. In order to make this work we needed to hardcode approximate operators in the parser, or we would have to create an approximate expression. ```APPROXIMATE_COUNT_DISTINCT(a, 0.01)``` would also do the job and is much easier to maintain. So, this PR **removes** this keyword.
- The old SQL Parser supports ```LIMIT``` clauses in nested queries. This is **not supported** anymore. See https://github.com/apache/spark/pull/10689 for the rationale for this.
- Hive has a charset name char set literal combination it supports, for instance the following expression ```_ISO-8859-1 0x4341464562616265``` would yield this string: ```CAFEbabe```. Hive will only allow charset names to start with an underscore. This is quite annoying in spark because as soon as you use a tuple names will start with an underscore. In this PR we **remove** this feature from the parser. It would be quite easy to implement such a feature as an Expression later on.
- Hive and the SQL Parser treat decimal literals differently. Hive will turn any decimal into a ```Double``` whereas the SQL Parser would convert a non-scientific decimal into a ```BigDecimal```, and would turn a scientific decimal into a Double. We follow Hive's behavior here. The new parser supports a big decimal literal, for instance: ```81923801.42BD```, which can be used when a big decimal is needed.
cc rxin viirya marmbrus yhuai cloud-fan
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#10745 from hvanhovell/SPARK-12575-2.
We made it a `NamedExpression` to workaroud some hacky cases long time ago, and now seems it's safe to remove it.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10765 from cloud-fan/minor.
The goal of this PR is to eliminate unnecessary translations when there are back-to-back `MapPartitions` operations. In order to achieve this I also made the following simplifications:
- Operators no longer have hold encoders, instead they have only the expressions that they need. The benefits here are twofold: the expressions are visible to transformations so go through the normal resolution/binding process. now that they are visible we can change them on a case by case basis.
- Operators no longer have type parameters. Since the engine is responsible for its own type checking, having the types visible to the complier was an unnecessary complication. We still leverage the scala compiler in the companion factory when constructing a new operator, but after this the types are discarded.
Deferred to a follow up PR:
- Remove as much of the resolution/binding from Dataset/GroupedDataset as possible. We should still eagerly check resolution and throw an error though in the case of mismatches for an `as` operation.
- Eliminate serializations in more cases by adding more cases to `EliminateSerialization`
Author: Michael Armbrust <michael@databricks.com>
Closes#10747 from marmbrus/encoderExpressions.
The generated code for CaseWhen uses a control variable "got" to make sure we do not evaluate more branches once a branch is true. Changing that to generate just simple "if / else" would be slightly more efficient.
This closes#10737.
Author: Reynold Xin <rxin@databricks.com>
Closes#10755 from rxin/SPARK-12771.
This PR makes bucketing and exchange share one common hash algorithm, so that we can guarantee the data distribution is same between shuffle and bucketed data source, which enables us to only shuffle one side when join a bucketed table and a normal one.
This PR also fixes the tests that are broken by the new hash behaviour in shuffle.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10703 from cloud-fan/use-hash-expr-in-shuffle.
This pull request rewrites CaseWhen expression to break the single, monolithic "branches" field into a sequence of tuples (Seq[(condition, value)]) and an explicit optional elseValue field.
Prior to this pull request, each even position in "branches" represents the condition for each branch, and each odd position represents the value for each branch. The use of them have been pretty confusing with a lot sliding windows or grouped(2) calls.
Author: Reynold Xin <rxin@databricks.com>
Closes#10734 from rxin/simplify-case.
Fix the style violation (space before , and :).
This PR is a followup for #10643 and rework of #10685 .
Author: Kousuke Saruta <sarutak@oss.nttdata.co.jp>
Closes#10732 from sarutak/SPARK-12692-followup-sql.
This patch removes CaseKeyWhen expression and replaces it with a factory method that generates the equivalent CaseWhen. This reduces the amount of code we'd need to maintain in the future for both code generation and optimizer.
Note that we introduced CaseKeyWhen to avoid duplicate evaluations of the key. This is no longer a problem because we now have common subexpression elimination.
Author: Reynold Xin <rxin@databricks.com>
Closes#10722 from rxin/SPARK-12768.
This pull request does a few small things:
1. Separated if simplification from BooleanSimplification and created a new rule SimplifyConditionals. In the future we can also simplify other conditional expressions here.
2. Added unit test for SimplifyConditionals.
3. Renamed SimplifyCaseConversionExpressionsSuite to SimplifyStringCaseConversionSuite
Author: Reynold Xin <rxin@databricks.com>
Closes#10716 from rxin/SPARK-12762.
Fix the style violation (space before , and :).
This PR is a followup for #10643.
Author: Kousuke Saruta <sarutak@oss.nttdata.co.jp>
Closes#10718 from sarutak/SPARK-12692-followup-sql.
Scala syntax allows binary case classes to be used as infix operator in pattern matching. This PR makes use of this syntax sugar to make `BooleanSimplification` more readable.
Author: Cheng Lian <lian@databricks.com>
Closes#10445 from liancheng/boolean-simplification-simplification.
The PR allows us to use the new SQL parser to parse SQL expressions such as: ```1 + sin(x*x)```
We enable this functionality in this PR, but we will not start using this actively yet. This will be done as soon as we have reached grammar parity with the existing parser stack.
cc rxin
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#10649 from hvanhovell/SPARK-12576.
Turn import ordering violations into build errors, plus a few adjustments
to account for how the checker behaves. I'm a little on the fence about
whether the existing code is right, but it's easier to appease the checker
than to discuss what's the more correct order here.
Plus a few fixes to imports that cropped in since my recent cleanups.
Author: Marcelo Vanzin <vanzin@cloudera.com>
Closes#10612 from vanzin/SPARK-3873-enable.
This PR tries to enable Spark SQL to convert resolved logical plans back to SQL query strings. For now, the major use case is to canonicalize Spark SQL native view support. The major entry point is `SQLBuilder.toSQL`, which returns an `Option[String]` if the logical plan is recognized.
The current version is still in WIP status, and is quite limited. Known limitations include:
1. The logical plan must be analyzed but not optimized
The optimizer erases `Subquery` operators, which contain necessary scope information for SQL generation. Future versions should be able to recover erased scope information by inserting subqueries when necessary.
1. The logical plan must be created using HiveQL query string
Query plans generated by composing arbitrary DataFrame API combinations are not supported yet. Operators within these query plans need to be rearranged into a canonical form that is more suitable for direct SQL generation. For example, the following query plan
```
Filter (a#1 < 10)
+- MetastoreRelation default, src, None
```
need to be canonicalized into the following form before SQL generation:
```
Project [a#1, b#2, c#3]
+- Filter (a#1 < 10)
+- MetastoreRelation default, src, None
```
Otherwise, the SQL generation process will have to handle a large number of special cases.
1. Only a fraction of expressions and basic logical plan operators are supported in this PR
Currently, 95.7% (1720 out of 1798) query plans in `HiveCompatibilitySuite` can be successfully converted to SQL query strings.
Known unsupported components are:
- Expressions
- Part of math expressions
- Part of string expressions (buggy?)
- Null expressions
- Calendar interval literal
- Part of date time expressions
- Complex type creators
- Special `NOT` expressions, e.g. `NOT LIKE` and `NOT IN`
- Logical plan operators/patterns
- Cube, rollup, and grouping set
- Script transformation
- Generator
- Distinct aggregation patterns that fit `DistinctAggregationRewriter` analysis rule
- Window functions
Support for window functions, generators, and cubes etc. will be added in follow-up PRs.
This PR leverages `HiveCompatibilitySuite` for testing SQL generation in a "round-trip" manner:
* For all select queries, we try to convert it back to SQL
* If the query plan is convertible, we parse the generated SQL into a new logical plan
* Run the new logical plan instead of the original one
If the query plan is inconvertible, the test case simply falls back to the original logic.
TODO
- [x] Fix failed test cases
- [x] Support for more basic expressions and logical plan operators (e.g. distinct aggregation etc.)
- [x] Comments and documentation
Author: Cheng Lian <lian@databricks.com>
Closes#10541 from liancheng/sql-generation.
JIRA: https://issues.apache.org/jira/browse/SPARK-12687
Some queries such as `(select 1 as a) union (select 2 as a)` can't work. This patch fixes it.
Author: Liang-Chi Hsieh <viirya@gmail.com>
Closes#10660 from viirya/fix-union.
Fix most build warnings: mostly deprecated API usages. I'll annotate some of the changes below. CC rxin who is leading the charge to remove the deprecated APIs.
Author: Sean Owen <sowen@cloudera.com>
Closes#10570 from srowen/SPARK-12618.
Use multi-line string literals for ExpressionDescription with ``// scalastyle:off line.size.limit`` and ``// scalastyle:on line.size.limit``
The policy is here, as describe at https://github.com/apache/spark/pull/10488
Let's use multi-line string literals. If we have to have a line with more than 100 characters, let's use ``// scalastyle:off line.size.limit`` and ``// scalastyle:on line.size.limit`` to just bypass the line number requirement.
Author: Kazuaki Ishizaki <ishizaki@jp.ibm.com>
Closes#10524 from kiszk/SPARK-12580.
To avoid to have a huge Java source (over 64K loc), that can't be compiled.
cc hvanhovell
Author: Davies Liu <davies@databricks.com>
Closes#10624 from davies/split_ident.
This PR moves a major part of the new SQL parser to Catalyst. This is a prelude to start using this parser for all of our SQL parsing. The following key changes have been made:
The ANTLR Parser & Supporting classes have been moved to the Catalyst project. They are now part of the ```org.apache.spark.sql.catalyst.parser``` package. These classes contained quite a bit of code that was originally from the Hive project, I have added aknowledgements whenever this applied. All Hive dependencies have been factored out. I have also taken this chance to clean-up the ```ASTNode``` class, and to improve the error handling.
The HiveQl object that provides the functionality to convert an AST into a LogicalPlan has been refactored into three different classes, one for every SQL sub-project:
- ```CatalystQl```: This implements Query and Expression parsing functionality.
- ```SparkQl```: This is a subclass of CatalystQL and provides SQL/Core only functionality such as Explain and Describe.
- ```HiveQl```: This is a subclass of ```SparkQl``` and this adds Hive-only functionality to the parser such as Analyze, Drop, Views, CTAS & Transforms. This class still depends on Hive.
cc rxin
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#10583 from hvanhovell/SPARK-12575.
JIRA: https://issues.apache.org/jira/browse/SPARK-12439
In toCatalystArray, we should look at the data type returned by dataTypeFor instead of silentSchemaFor, to determine if the element is native type. An obvious problem is when the element is Option[Int] class, catalsilentSchemaFor will return Int, then we will wrongly recognize the element is native type.
There is another problem when using Option as array element. When we encode data like Seq(Some(1), Some(2), None) with encoder, we will use MapObjects to construct an array for it later. But in MapObjects, we don't check if the return value of lambdaFunction is null or not. That causes a bug that the decoded data for Seq(Some(1), Some(2), None) would be Seq(1, 2, -1), instead of Seq(1, 2, null).
Author: Liang-Chi Hsieh <viirya@gmail.com>
Closes#10391 from viirya/fix-catalystarray.
address comments in #10435
This makes the API easier to use if user programmatically generate the call to hash, and they will get analysis exception if the arguments of hash is empty.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10588 from cloud-fan/hash.
just write the arguments into unsafe row and use murmur3 to calculate hash code
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10435 from cloud-fan/hash-expr.
The reader was previously not setting the row length meaning it was wrong if there were variable
length columns. This problem does not manifest usually, since the value in the column is correct and
projecting the row fixes the issue.
Author: Nong Li <nong@databricks.com>
Closes#10576 from nongli/spark-12589.
This PR enable cube/rollup as function, so they can be used as this:
```
select a, b, sum(c) from t group by rollup(a, b)
```
Author: Davies Liu <davies@databricks.com>
Closes#10522 from davies/rollup.
It is currently possible to change the values of the supposedly immutable ```GenericRow``` and ```GenericInternalRow``` classes. This is caused by the fact that scala's ArrayOps ```toArray``` (returned by calling ```toSeq```) will return the backing array instead of a copy. This PR fixes this problem.
This PR was inspired by https://github.com/apache/spark/pull/10374 by apo1.
cc apo1 sarutak marmbrus cloud-fan nongli (everyone in the previous conversation).
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#10553 from hvanhovell/SPARK-12421.
Avoiding the the No such table exception and throwing analysis exception as per the bug: SPARK-12533
Author: thomastechs <thomas.sebastian@tcs.com>
Closes#10529 from thomastechs/topic-branch.
Right now, numFields will be passed in by pointTo(), then bitSetWidthInBytes is calculated, making pointTo() a little bit heavy.
It should be part of constructor of UnsafeRow.
Author: Davies Liu <davies@databricks.com>
Closes#10528 from davies/numFields.
Most of cases we should propagate null when call `NewInstance`, and so far there is only one case we should stop null propagation: create product/java bean. So I think it makes more sense to propagate null by dafault.
This also fixes a bug when encode null array/map, which is firstly discovered in https://github.com/apache/spark/pull/10401
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10443 from cloud-fan/encoder.
```
org.apache.spark.sql.AnalysisException: cannot resolve 'value' given input columns text;
```
lets put a `:` after `columns` and put the columns in `[]` so that they match the toString of DataFrame.
Author: gatorsmile <gatorsmile@gmail.com>
Closes#10518 from gatorsmile/improveAnalysisExceptionMsg.
In Spark we allow UDFs to declare its expected input types in order to apply type coercion. The expected input type parameter takes a Seq[DataType] and uses Nil when no type coercion is applied. It makes more sense to take Option[Seq[DataType]] instead, so we can differentiate a no-arg function vs function with no expected input type specified.
Author: Reynold Xin <rxin@databricks.com>
Closes#10504 from rxin/SPARK-12549.
When explain any plan with Generate, we will see an exclamation mark in the plan. Normally, when we see this mark, it means the plan has an error. This PR is to correct the `missingInput` in `Generate`.
For example,
```scala
val df = Seq((1, "a b c"), (2, "a b"), (3, "a")).toDF("number", "letters")
val df2 =
df.explode('letters) {
case Row(letters: String) => letters.split(" ").map(Tuple1(_)).toSeq
}
df2.explain(true)
```
Before the fix, the plan is like
```
== Parsed Logical Plan ==
'Generate UserDefinedGenerator('letters), true, false, None
+- Project [_1#0 AS number#2,_2#1 AS letters#3]
+- LocalRelation [_1#0,_2#1], [[1,a b c],[2,a b],[3,a]]
== Analyzed Logical Plan ==
number: int, letters: string, _1: string
Generate UserDefinedGenerator(letters#3), true, false, None, [_1#8]
+- Project [_1#0 AS number#2,_2#1 AS letters#3]
+- LocalRelation [_1#0,_2#1], [[1,a b c],[2,a b],[3,a]]
== Optimized Logical Plan ==
Generate UserDefinedGenerator(letters#3), true, false, None, [_1#8]
+- LocalRelation [number#2,letters#3], [[1,a b c],[2,a b],[3,a]]
== Physical Plan ==
!Generate UserDefinedGenerator(letters#3), true, false, [number#2,letters#3,_1#8]
+- LocalTableScan [number#2,letters#3], [[1,a b c],[2,a b],[3,a]]
```
**Updates**: The same issues are also found in the other four Dataset operators: `MapPartitions`/`AppendColumns`/`MapGroups`/`CoGroup`. Fixed all these four.
Author: gatorsmile <gatorsmile@gmail.com>
Author: xiaoli <lixiao1983@gmail.com>
Author: Xiao Li <xiaoli@Xiaos-MacBook-Pro.local>
Closes#10393 from gatorsmile/generateExplain.
Moved (case) classes Strategy, Once, FixedPoint and Batch to the companion object. This is necessary if we want to have the Optimizer easily extendable in the following sense: Usually a user wants to add additional rules, and just take the ones that are already there. However, inner classes made that impossible since the code did not compile
This allows easy extension of existing Optimizers see the DefaultOptimizerExtendableSuite for a corresponding test case.
Author: Stephan Kessler <stephan.kessler@sap.com>
Closes#10174 from stephankessler/SPARK-7727.
Accessing null elements in an array field fails when tungsten is enabled.
It works in Spark 1.3.1, and in Spark > 1.5 with Tungsten disabled.
This PR solves this by checking if the accessed element in the array field is null, in the generated code.
Example:
```
// Array of String
case class AS( as: Seq[String] )
val dfAS = sc.parallelize( Seq( AS ( Seq("a",null,"b") ) ) ).toDF
dfAS.registerTempTable("T_AS")
for (i <- 0 to 2) { println(i + " = " + sqlContext.sql(s"select as[$i] from T_AS").collect.mkString(","))}
```
With Tungsten disabled:
```
0 = [a]
1 = [null]
2 = [b]
```
With Tungsten enabled:
```
0 = [a]
15/12/22 09:32:50 ERROR Executor: Exception in task 7.0 in stage 1.0 (TID 15)
java.lang.NullPointerException
at org.apache.spark.sql.catalyst.expressions.UnsafeRowWriters$UTF8StringWriter.getSize(UnsafeRowWriters.java:90)
at org.apache.spark.sql.catalyst.expressions.GeneratedClass$SpecificUnsafeProjection.apply(Unknown Source)
at org.apache.spark.sql.execution.TungstenProject$$anonfun$3$$anonfun$apply$3.apply(basicOperators.scala:90)
at org.apache.spark.sql.execution.TungstenProject$$anonfun$3$$anonfun$apply$3.apply(basicOperators.scala:88)
at scala.collection.Iterator$$anon$11.next(Iterator.scala:328)
at scala.collection.Iterator$$anon$11.next(Iterator.scala:328)
at scala.collection.Iterator$class.foreach(Iterator.scala:727)
at scala.collection.AbstractIterator.foreach(Iterator.scala:1157)
```
Author: pierre-borckmans <pierre.borckmans@realimpactanalytics.com>
Closes#10429 from pierre-borckmans/SPARK-12477_Tungsten-Projection-Null-Element-In-Array.
When the filter is ```"b in ('1', '2')"```, the filter is not pushed down to Parquet. Thanks!
Author: gatorsmile <gatorsmile@gmail.com>
Author: xiaoli <lixiao1983@gmail.com>
Author: Xiao Li <xiaoli@Xiaos-MacBook-Pro.local>
Closes#10278 from gatorsmile/parquetFilterNot.
When creating extractors for product types (i.e. case classes and tuples), a null check is missing, thus we always assume input product values are non-null.
This PR adds a null check in the extractor expression for product types. The null check is stripped off for top level product fields, which are mapped to the outermost `Row`s, since they can't be null.
Thanks cloud-fan for helping investigating this issue!
Author: Cheng Lian <lian@databricks.com>
Closes#10431 from liancheng/spark-12478.top-level-null-field.
Compare both left and right side of the case expression ignoring nullablity when checking for type equality.
Author: Dilip Biswal <dbiswal@us.ibm.com>
Closes#10156 from dilipbiswal/spark-12102.
First try, not sure how much information we need to provide in the usage part.
Author: Xiu Guo <xguo27@gmail.com>
Closes#10423 from xguo27/SPARK-12456.
This PR adds a new expression `AssertNotNull` to ensure non-nullable fields of products and case classes don't receive null values at runtime.
Author: Cheng Lian <lian@databricks.com>
Closes#10331 from liancheng/dataset-nullability-check.
Based on the suggestions from marmbrus , added logical/physical operators for Range for improving the performance.
Also added another API for resolving the JIRA Spark-12150.
Could you take a look at my implementation, marmbrus ? If not good, I can rework it. : )
Thank you very much!
Author: gatorsmile <gatorsmile@gmail.com>
Closes#10335 from gatorsmile/rangeOperators.
When a DataFrame or Dataset has a long schema, we should intelligently truncate to avoid flooding the screen with unreadable information.
// Standard output
[a: int, b: int]
// Truncate many top level fields
[a: int, b, string ... 10 more fields]
// Truncate long inner structs
[a: struct<a: Int ... 10 more fields>]
Author: Dilip Biswal <dbiswal@us.ibm.com>
Closes#10373 from dilipbiswal/spark-12398.
Now `StaticInvoke` receives `Any` as a object and `StaticInvoke` can be serialized but sometimes the object passed is not serializable.
For example, following code raises Exception because `RowEncoder#extractorsFor` invoked indirectly makes `StaticInvoke`.
```
case class TimestampContainer(timestamp: java.sql.Timestamp)
val rdd = sc.parallelize(1 to 2).map(_ => TimestampContainer(System.currentTimeMillis))
val df = rdd.toDF
val ds = df.as[TimestampContainer]
val rdd2 = ds.rdd <----------------- invokes extractorsFor indirectory
```
I'll add test cases.
Author: Kousuke Saruta <sarutak@oss.nttdata.co.jp>
Author: Michael Armbrust <michael@databricks.com>
Closes#10357 from sarutak/SPARK-12404.
This could simplify the generated code for expressions that is not nullable.
This PR fix lots of bugs about nullability.
Author: Davies Liu <davies@databricks.com>
Closes#10333 from davies/skip_nullable.
Description of the problem from cloud-fan
Actually this line: https://github.com/apache/spark/blob/branch-1.5/sql/core/src/main/scala/org/apache/spark/sql/DataFrame.scala#L689
When we use `selectExpr`, we pass in `UnresolvedFunction` to `DataFrame.select` and fall in the last case. A workaround is to do special handling for UDTF like we did for `explode`(and `json_tuple` in 1.6), wrap it with `MultiAlias`.
Another workaround is using `expr`, for example, `df.select(expr("explode(a)").as(Nil))`, I think `selectExpr` is no longer needed after we have the `expr` function....
Author: Dilip Biswal <dbiswal@us.ibm.com>
Closes#9981 from dilipbiswal/spark-11619.
This PR removes Hive windows functions from Spark and replaces them with (native) Spark ones. The PR is on par with Hive in terms of features.
This has the following advantages:
* Better memory management.
* The ability to use spark UDAFs in Window functions.
cc rxin / yhuai
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#9819 from hvanhovell/SPARK-8641-2.
I think it was a mistake, and we have not catched it so far until https://github.com/apache/spark/pull/10260 which begin to check if the `fromRowExpression` is resolved.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10263 from cloud-fan/encoder.
Currently, we could generate different plans for query with single distinct (depends on spark.sql.specializeSingleDistinctAggPlanning), one works better on low cardinality columns, the other
works better for high cardinality column (default one).
This PR change to generate a single plan (three aggregations and two exchanges), which work better in both cases, then we could safely remove the flag `spark.sql.specializeSingleDistinctAggPlanning` (introduced in 1.6).
For a query like `SELECT COUNT(DISTINCT a) FROM table` will be
```
AGG-4 (count distinct)
Shuffle to a single reducer
Partial-AGG-3 (count distinct, no grouping)
Partial-AGG-2 (grouping on a)
Shuffle by a
Partial-AGG-1 (grouping on a)
```
This PR also includes large refactor for aggregation (reduce 500+ lines of code)
cc yhuai nongli marmbrus
Author: Davies Liu <davies@databricks.com>
Closes#10228 from davies/single_distinct.
in https://github.com/apache/spark/pull/10133 we found that, we shoud ensure the children of `TreeNode` are all accessible in the `productIterator`, or the behavior will be very confusing.
In this PR, I try to fix this problem by expsing the `loopVar`.
This also fixes SPARK-12131 which is caused by the hacky `MapObjects`.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10239 from cloud-fan/map-objects.
Delays application of ResolvePivot until all aggregates are resolved to prevent problems with UnresolvedFunction and adds unit test
Author: Andrew Ray <ray.andrew@gmail.com>
Closes#10202 from aray/sql-pivot-unresolved-function.
This PR is to add three more data types into Encoder, including `BigDecimal`, `Date` and `Timestamp`.
marmbrus cloud-fan rxin Could you take a quick look at these three types? Not sure if it can be merged to 1.6. Thank you very much!
Author: gatorsmile <gatorsmile@gmail.com>
Closes#10188 from gatorsmile/dataTypesinEncoder.
checked with hive, greatest/least should cast their children to a tightest common type,
i.e. `(int, long) => long`, `(int, string) => error`, `(decimal(10,5), decimal(5, 10)) => error`
Author: Wenchen Fan <wenchen@databricks.com>
Closes#10196 from cloud-fan/type-coercion.
Currently, the order of joins is exactly the same as SQL query, some conditions may not pushed down to the correct join, then those join will become cross product and is extremely slow.
This patch try to re-order the inner joins (which are common in SQL query), pick the joins that have self-contain conditions first, delay those that does not have conditions.
After this patch, the TPCDS query Q64/65 can run hundreds times faster.
cc marmbrus nongli
Author: Davies Liu <davies@databricks.com>
Closes#10073 from davies/reorder_joins.
When \u appears in a comment block (i.e. in /**/), code gen will break. So, in Expression and CodegenFallback, we escape \u to \\u.
yhuai Please review it. I did reproduce it and it works after the fix. Thanks!
Author: gatorsmile <gatorsmile@gmail.com>
Closes#10155 from gatorsmile/escapeU.
We should upgrade to SBT 0.13.9, since this is a requirement in order to use SBT's new Maven-style resolution features (which will be done in a separate patch, because it's blocked by some binary compatibility issues in the POM reader plugin).
I also upgraded Scalastyle to version 0.8.0, which was necessary in order to fix a Scala 2.10.5 compatibility issue (see https://github.com/scalastyle/scalastyle/issues/156). The newer Scalastyle is slightly stricter about whitespace surrounding tokens, so I fixed the new style violations.
Author: Josh Rosen <joshrosen@databricks.com>
Closes#10112 from JoshRosen/upgrade-to-sbt-0.13.9.
This replaces https://github.com/apache/spark/pull/9696
Invoke Checkstyle and print any errors to the console, failing the step.
Use Google's style rules modified according to
https://cwiki.apache.org/confluence/display/SPARK/Spark+Code+Style+Guide
Some important checks are disabled (see TODOs in `checkstyle.xml`) due to
multiple violations being present in the codebase.
Suggest fixing those TODOs in a separate PR(s).
More on Checkstyle can be found on the [official website](http://checkstyle.sourceforge.net/).
Sample output (from [build 46345](https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/46345/consoleFull)) (duplicated because I run the build twice with different profiles):
> Checkstyle checks failed at following occurrences:
[ERROR] src/main/java/org/apache/spark/sql/execution/datasources/parquet/UnsafeRowParquetRecordReader.java:[217,7] (coding) MissingSwitchDefault: switch without "default" clause.
> [ERROR] src/main/java/org/apache/spark/sql/execution/datasources/parquet/SpecificParquetRecordReaderBase.java:[198,10] (modifier) ModifierOrder: 'protected' modifier out of order with the JLS suggestions.
> [ERROR] src/main/java/org/apache/spark/sql/execution/datasources/parquet/UnsafeRowParquetRecordReader.java:[217,7] (coding) MissingSwitchDefault: switch without "default" clause.
> [ERROR] src/main/java/org/apache/spark/sql/execution/datasources/parquet/SpecificParquetRecordReaderBase.java:[198,10] (modifier) ModifierOrder: 'protected' modifier out of order with the JLS suggestions.
> [error] running /home/jenkins/workspace/SparkPullRequestBuilder2/dev/lint-java ; received return code 1
Also fix some of the minor violations that didn't require sweeping changes.
Apologies for the previous botched PRs - I finally figured out the issue.
cr: JoshRosen, pwendell
> I state that the contribution is my original work, and I license the work to the project under the project's open source license.
Author: Dmitry Erastov <derastov@gmail.com>
Closes#9867 from dskrvk/master.
When examining plans of complex queries with multiple joins, a pain point of mine is that, it's hard to immediately see the sibling node of a specific query plan node. This PR adds tree lines for the tree string of a `TreeNode`, so that the result can be visually more intuitive.
Author: Cheng Lian <lian@databricks.com>
Closes#10099 from liancheng/prettier-tree-string.
Following up #10038.
We can use bitmasks to determine which grouping expressions need to be set as nullable.
cc yhuai
Author: Liang-Chi Hsieh <viirya@appier.com>
Closes#10067 from viirya/fix-cube-following.
create java version of `constructorFor` and `extractorFor` in `JavaTypeInference`
Author: Wenchen Fan <wenchen@databricks.com>
This patch had conflicts when merged, resolved by
Committer: Michael Armbrust <michael@databricks.com>
Closes#9937 from cloud-fan/pojo.
When we build the `fromRowExpression` for an encoder, we set up a lot of "unresolved" stuff and lost the required data type, which may lead to runtime error if the real type doesn't match the encoder's schema.
For example, we build an encoder for `case class Data(a: Int, b: String)` and the real type is `[a: int, b: long]`, then we will hit runtime error and say that we can't construct class `Data` with int and long, because we lost the information that `b` should be a string.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9840 from cloud-fan/err-msg.
JIRA: https://issues.apache.org/jira/browse/SPARK-11949
The result of cube plan uses incorrect schema. The schema of cube result should set nullable property to true because the grouping expressions will have null values.
Author: Liang-Chi Hsieh <viirya@appier.com>
Closes#10038 from viirya/fix-cube.
JIRA: https://issues.apache.org/jira/browse/SPARK-12018
The code of common subexpression elimination can be factored and simplified. Some unnecessary variables can be removed.
Author: Liang-Chi Hsieh <viirya@appier.com>
Closes#10009 from viirya/refactor-subexpr-eliminate.
In https://github.com/apache/spark/pull/9409 we enabled multi-column counting. The approach taken in that PR introduces a bit of overhead by first creating a row only to check if all of the columns are non-null.
This PR fixes that technical debt. Count now takes multiple columns as its input. In order to make this work I have also added support for multiple columns in the single distinct code path.
cc yhuai
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#10015 from hvanhovell/SPARK-12024.
When calling `get_json_object` for the following two cases, both results are `"null"`:
```scala
val tuple: Seq[(String, String)] = ("5", """{"f1": null}""") :: Nil
val df: DataFrame = tuple.toDF("key", "jstring")
val res = df.select(functions.get_json_object($"jstring", "$.f1")).collect()
```
```scala
val tuple2: Seq[(String, String)] = ("5", """{"f1": "null"}""") :: Nil
val df2: DataFrame = tuple2.toDF("key", "jstring")
val res3 = df2.select(functions.get_json_object($"jstring", "$.f1")).collect()
```
Fixed the problem and also added a test case.
Author: gatorsmile <gatorsmile@gmail.com>
Closes#10018 from gatorsmile/get_json_object.
This is a followup for https://github.com/apache/spark/pull/9959.
I added more documentation and rewrote some monadic code into simpler ifs.
Author: Reynold Xin <rxin@databricks.com>
Closes#9995 from rxin/SPARK-11973.
this is based on https://github.com/apache/spark/pull/9844, with some bug fix and clean up.
The problems is that, normal operator should be resolved based on its child, but `Sort` operator can also be resolved based on its grandchild. So we have 3 rules that can resolve `Sort`: `ResolveReferences`, `ResolveSortReferences`(if grandchild is `Project`) and `ResolveAggregateFunctions`(if grandchild is `Aggregate`).
For example, `select c1 as a , c2 as b from tab group by c1, c2 order by a, c2`, we need to resolve `a` and `c2` for `Sort`. Firstly `a` will be resolved in `ResolveReferences` based on its child, and when we reach `ResolveAggregateFunctions`, we will try to resolve both `a` and `c2` based on its grandchild, but failed because `a` is not a legal aggregate expression.
whoever merge this PR, please give the credit to dilipbiswal
Author: Dilip Biswal <dbiswal@us.ibm.com>
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9961 from cloud-fan/sort.
Currently, filter can't be pushed through aggregation with alias or literals, this patch fix that.
After this patch, the time of TPC-DS query 4 go down to 13 seconds from 141 seconds (10x improvements).
cc nongli yhuai
Author: Davies Liu <davies@databricks.com>
Closes#9959 from davies/push_filter2.
Right now, the expended start will include the name of expression as prefix for column, that's not better than without expending, we should not have the prefix.
Author: Davies Liu <davies@databricks.com>
Closes#9984 from davies/expand_star.
Currently pivot's signature looks like
```scala
scala.annotation.varargs
def pivot(pivotColumn: Column, values: Column*): GroupedData
scala.annotation.varargs
def pivot(pivotColumn: String, values: Any*): GroupedData
```
I think we can remove the one that takes "Column" types, since callers should always be passing in literals. It'd also be more clear if the values are not varargs, but rather Seq or java.util.List.
I also made similar changes for Python.
Author: Reynold Xin <rxin@databricks.com>
Closes#9929 from rxin/SPARK-11946.
we should pass in resolved encodera to logical `CoGroup` and bind them in physical `CoGroup`
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9928 from cloud-fan/cogroup.
We should use `InternalRow.isNullAt` to check if the field is null before calling `InternalRow.getXXX`
Thanks gatorsmile who discovered this bug.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9904 from cloud-fan/null.
Can someone review my code to make sure I'm not missing anything? Thanks!
Author: Xiu Guo <xguo27@gmail.com>
Author: Xiu Guo <guoxi@us.ibm.com>
Closes#9612 from xguo27/SPARK-11628.
1. Renamed map to mapGroup, flatMap to flatMapGroup.
2. Renamed asKey -> keyAs.
3. Added more documentation.
4. Changed type parameter T to V on GroupedDataset.
5. Added since versions for all functions.
Author: Reynold Xin <rxin@databricks.com>
Closes#9880 from rxin/SPARK-11899.
seems scala 2.11 doesn't support: define private methods in `trait xxx` and use it in `object xxx extend xxx`.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9879 from cloud-fan/follow.
This mainly moves SqlNewHadoopRDD to the sql package. There is some state that is
shared between core and I've left that in core. This allows some other associated
minor cleanup.
Author: Nong Li <nong@databricks.com>
Closes#9845 from nongli/spark-11787.
#theScaryParts (i.e. changes to the repl, executor classloaders and codegen)...
Author: Michael Armbrust <michael@databricks.com>
Author: Yin Huai <yhuai@databricks.com>
Closes#9825 from marmbrus/dataset-replClasses2.
Hive has since changed this behavior as well. https://issues.apache.org/jira/browse/HIVE-3454
Author: Nong Li <nong@databricks.com>
Author: Nong Li <nongli@gmail.com>
Author: Yin Huai <yhuai@databricks.com>
Closes#9685 from nongli/spark-11724.
before this PR, when users try to get an encoder for an un-supported class, they will only get a very simple error message like `Encoder for type xxx is not supported`.
After this PR, the error message become more friendly, for example:
```
No Encoder found for abc.xyz.NonEncodable
- array element class: "abc.xyz.NonEncodable"
- field (class: "scala.Array", name: "arrayField")
- root class: "abc.xyz.AnotherClass"
```
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9810 from cloud-fan/error-message.
JIRA: https://issues.apache.org/jira/browse/SPARK-11817
Instead of return None, we should truncate the fractional seconds to prevent inserting NULL.
Author: Liang-Chi Hsieh <viirya@appier.com>
Closes#9834 from viirya/truncate-fractional-sec.
This PR has the following optimization:
1) The greatest/least already does the null-check, so the `If` and `IsNull` are not necessary.
2) In greatest/least, it should initialize the result using the first child (removing one block).
3) For primitive types, the generated greater expression is too complicated (`a > b ? 1 : (a < b) ? -1 : 0) > 0`), should be as simple as `a > b`
Combine these optimization, this could improve the performance of `ss_max` query by 30%.
Author: Davies Liu <davies@databricks.com>
Closes#9846 from davies/improve_max.
Fixes bug with grouping sets (including cube/rollup) where aggregates that included grouping expressions would return the wrong (null) result.
Also simplifies the analyzer rule a bit and leaves column pruning to the optimizer.
Added multiple unit tests to DataFrameAggregateSuite and verified it passes hive compatibility suite:
```
build/sbt -Phive -Dspark.hive.whitelist='groupby.*_grouping.*' 'test-only org.apache.spark.sql.hive.execution.HiveCompatibilitySuite'
```
This is an alternative to pr https://github.com/apache/spark/pull/9419 but I think its better as it simplifies the analyzer rule instead of adding another special case to it.
Author: Andrew Ray <ray.andrew@gmail.com>
Closes#9815 from aray/groupingset-agg-fix.
After some experiment, I found it's not convenient to have separate encoder builders: `FlatEncoder` and `ProductEncoder`. For example, when create encoders for `ScalaUDF`, we have no idea if the type `T` is flat or not. So I revert the splitting change in https://github.com/apache/spark/pull/9693, while still keeping the bug fixes and tests.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9726 from cloud-fan/follow.
The impact of this change is for a query that has a single distinct column and does not have any grouping expression like
`SELECT COUNT(DISTINCT a) FROM table`
The plan will be changed from
```
AGG-2 (count distinct)
Shuffle to a single reducer
Partial-AGG-2 (count distinct)
AGG-1 (grouping on a)
Shuffle by a
Partial-AGG-1 (grouping on 1)
```
to the following one (1.5 uses this)
```
AGG-2
AGG-1 (grouping on a)
Shuffle to a single reducer
Partial-AGG-1(grouping on a)
```
The first plan is more robust. However, to better benchmark the impact of this change, we should use 1.5's plan and use the conf of `spark.sql.specializeSingleDistinctAggPlanning` to control the plan.
Author: Yin Huai <yhuai@databricks.com>
Closes#9828 from yhuai/distinctRewriter.
We currently rely on the optimizer's constant folding to replace current_timestamp and current_date. However, this can still result in different values for different instances of current_timestamp/current_date if the optimizer is not running fast enough.
A better solution is to replace these functions in the analyzer in one shot.
Author: Reynold Xin <rxin@databricks.com>
Closes#9833 from rxin/SPARK-11849.
This patch adds an alternate to the Parquet RecordReader from the parquet-mr project
that is much faster for flat schemas. Instead of using the general converter mechanism
from parquet-mr, this directly uses the lower level APIs from parquet-columnar and a
customer RecordReader that directly assembles into UnsafeRows.
This is optionally disabled and only used for supported schemas.
Using the tpcds store sales table and doing a sum of increasingly more columns, the results
are:
For 1 Column:
Before: 11.3M rows/second
After: 18.2M rows/second
For 2 Columns:
Before: 7.2M rows/second
After: 11.2M rows/second
For 5 Columns:
Before: 2.9M rows/second
After: 4.5M rows/second
Author: Nong Li <nong@databricks.com>
Closes#9774 from nongli/parquet.
Also added some nicer error messages for incompatible types (private types and primitive types) for Kryo/Java encoder.
Author: Reynold Xin <rxin@databricks.com>
Closes#9823 from rxin/SPARK-11833.
Before this PR there were two things that would blow up if you called `df.as[MyClass]` if `MyClass` was defined in the REPL:
- [x] Because `classForName` doesn't work on the munged names returned by `tpe.erasure.typeSymbol.asClass.fullName`
- [x] Because we don't have anything to pass into the constructor for the `$outer` pointer.
Note that this PR is just adding the infrastructure for working with inner classes in encoder and is not yet sufficient to make them work in the REPL. Currently, the implementation show in 95cec7d413 is causing a bug that breaks code gen due to some interaction between janino and the `ExecutorClassLoader`. This will be addressed in a follow-up PR.
Author: Michael Armbrust <michael@databricks.com>
Closes#9602 from marmbrus/dataset-replClasses.
This patch refactors the existing Kryo encoder expressions and adds support for Java serialization.
Author: Reynold Xin <rxin@databricks.com>
Closes#9802 from rxin/SPARK-11810.
return Double.NaN for mean/average when count == 0 for all numeric types that is converted to Double, Decimal type continue to return null.
Author: JihongMa <linlin200605@gmail.com>
Closes#9705 from JihongMA/SPARK-11720.
If user use primitive parameters in UDF, there is no way for him to do the null-check for primitive inputs, so we are assuming the primitive input is null-propagatable for this case and return null if the input is null.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9770 from cloud-fan/udf.
I also found a bug with self-joins returning incorrect results in the Dataset API. Two test cases attached and filed SPARK-11803.
Author: Reynold Xin <rxin@databricks.com>
Closes#9789 from rxin/SPARK-11802.
Based on the comment of cloud-fan in https://github.com/apache/spark/pull/9216, update the AttributeReference's hashCode function by including the hashCode of the other attributes including name, nullable and qualifiers.
Here, I am not 100% sure if we should include name in the hashCode calculation, since the original hashCode calculation does not include it.
marmbrus cloud-fan Please review if the changes are good.
Author: gatorsmile <gatorsmile@gmail.com>
Closes#9761 from gatorsmile/hashCodeNamedExpression.
In the previous method, fields.toArray will cast java.util.List[StructField] into Array[Object] which can not cast into Array[StructField], thus when invoking this method will throw "java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to [Lorg.apache.spark.sql.types.StructField;"
I directly cast java.util.List[StructField] into Array[StructField] in this patch.
Author: mayuanwen <mayuanwen@qiyi.com>
Closes#9649 from jackieMaKing/Spark-11679.
The randomly generated ArrayData used for the UDT `ExamplePoint` in `RowEncoderSuite` sometimes doesn't have enough elements. In this case, this test will fail. This patch is to fix it.
Author: Liang-Chi Hsieh <viirya@appier.com>
Closes#9757 from viirya/fix-randomgenerated-udt.
During executing PromoteStrings rule, if one side of binaryComparison is StringType and the other side is not StringType, the current code will promote(cast) the StringType to DoubleType, and if the StringType doesn't contain the numbers, it will get null value. So if it is doing <=> (NULL-safe equal) with Null, it will not filter anything, caused the problem reported by this jira.
I proposal to the changes through this PR, can you review my code changes ?
This problem only happen for <=>, other operators works fine.
scala> val filteredDF = df.filter(df("column") > (new Column(Literal(null))))
filteredDF: org.apache.spark.sql.DataFrame = [column: string]
scala> filteredDF.show
+------+
|column|
+------+
+------+
scala> val filteredDF = df.filter(df("column") === (new Column(Literal(null))))
filteredDF: org.apache.spark.sql.DataFrame = [column: string]
scala> filteredDF.show
+------+
|column|
+------+
+------+
scala> df.registerTempTable("DF")
scala> sqlContext.sql("select * from DF where 'column' = NULL")
res27: org.apache.spark.sql.DataFrame = [column: string]
scala> res27.show
+------+
|column|
+------+
+------+
Author: Kevin Yu <qyu@us.ibm.com>
Closes#9720 from kevinyu98/working_on_spark-11447.
This patch adds an alias for current_timestamp (now function).
Also fixes SPARK-9196 to re-enable the test case for current_timestamp.
Author: Reynold Xin <rxin@databricks.com>
Closes#9753 from rxin/SPARK-11768.
This fix is to change the equals method to check all of the specified fields for equality of AttributeReference.
Author: gatorsmile <gatorsmile@gmail.com>
Closes#9216 from gatorsmile/namedExpressEqual.
Invocation of getters for type extending AnyVal returns default value (if field value is null) instead of throwing NPE. Please check comments for SPARK-11553 issue for more details.
Author: Bartlomiej Alberski <bartlomiej.alberski@allegrogroup.com>
Closes#9642 from alberskib/bugfix/SPARK-11553.
These 2 are very similar, we can consolidate them into one.
Also add tests for it and fix a bug.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9729 from cloud-fan/tuple.
JIRA: https://issues.apache.org/jira/browse/SPARK-11743
RowEncoder doesn't support UserDefinedType now. We should add the support for it.
Author: Liang-Chi Hsieh <viirya@appier.com>
Closes#9712 from viirya/rowencoder-udt.
code snippet to reproduce it:
```
TimeZone.setDefault(TimeZone.getTimeZone("Asia/Shanghai"))
val t = Timestamp.valueOf("1900-06-11 12:14:50.789")
val us = fromJavaTimestamp(t)
assert(getSeconds(us) === t.getSeconds)
```
it will be good to add a regression test for it, but the reproducing code need to change the default timezone, and even we change it back, the `lazy val defaultTimeZone` in `DataTimeUtils` is fixed.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9728 from cloud-fan/seconds.
also add more tests for encoders, and fix bugs that I found:
* when convert array to catalyst array, we can only skip element conversion for native types(e.g. int, long, boolean), not `AtomicType`(String is AtomicType but we need to convert it)
* we should also handle scala `BigDecimal` when convert from catalyst `Decimal`.
* complex map type should be supported
other issues that still in investigation:
* encode java `BigDecimal` and decode it back, seems we will loss precision info.
* when encode case class that defined inside a object, `ClassNotFound` exception will be thrown.
I'll remove unused code in a follow-up PR.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9693 from cloud-fan/split.
* rename `AppendColumn` to `AppendColumns` to be consistent with the physical plan name.
* clean up stale comments.
* always pass in resolved encoder to `TypedColumn.withInputType`(test added)
* enable a mistakenly disabled java test.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9688 from cloud-fan/follow.
This PR adds a new method, `reduce`, to `GroupedDataset`, which allows similar operations to `reduceByKey` on a traditional `PairRDD`.
```scala
val ds = Seq("abc", "xyz", "hello").toDS()
ds.groupBy(_.length).reduce(_ + _).collect() // not actually commutative :P
res0: Array(3 -> "abcxyz", 5 -> "hello")
```
While implementing this method and its test cases several more deficiencies were found in our encoder handling. Specifically, in order to support positional resolution, named resolution and tuple composition, it is important to keep the unresolved encoder around and to use it when constructing new `Datasets` with the same object type but different output attributes. We now divide the encoder lifecycle into three phases (that mirror the lifecycle of standard expressions) and have checks at various boundaries:
- Unresoved Encoders: all users facing encoders (those constructed by implicits, static methods, or tuple composition) are unresolved, meaning they have only `UnresolvedAttributes` for named fields and `BoundReferences` for fields accessed by ordinal.
- Resolved Encoders: internal to a `[Grouped]Dataset` the encoder is resolved, meaning all input has been resolved to a specific `AttributeReference`. Any encoders that are placed into a logical plan for use in object construction should be resolved.
- BoundEncoder: Are constructed by physical plans, right before actual conversion from row -> object is performed.
It is left to future work to add explicit checks for resolution and provide good error messages when it fails. We might also consider enforcing the above constraints in the type system (i.e. `fromRow` only exists on a `ResolvedEncoder`), but we should probably wait before spending too much time on this.
Author: Michael Armbrust <michael@databricks.com>
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9673 from marmbrus/pr/9628.
switched stddev support from DeclarativeAggregate to ImperativeAggregate.
Author: JihongMa <linlin200605@gmail.com>
Closes#9380 from JihongMA/SPARK-11420.
`to_unix_timestamp` is the deterministic version of `unix_timestamp`, as it accepts at least one parameters.
Since the behavior here is quite similar to `unix_timestamp`, I think the dataframe API is not necessary here.
Author: Daoyuan Wang <daoyuan.wang@intel.com>
Closes#9347 from adrian-wang/to_unix_timestamp.
This adds a pivot method to the dataframe api.
Following the lead of cube and rollup this adds a Pivot operator that is translated into an Aggregate by the analyzer.
Currently the syntax is like:
~~courseSales.pivot(Seq($"year"), $"course", Seq("dotNET", "Java"), sum($"earnings"))~~
~~Would we be interested in the following syntax also/alternatively? and~~
courseSales.groupBy($"year").pivot($"course", "dotNET", "Java").agg(sum($"earnings"))
//or
courseSales.groupBy($"year").pivot($"course").agg(sum($"earnings"))
Later we can add it to `SQLParser`, but as Hive doesn't support it we cant add it there, right?
~~Also what would be the suggested Java friendly method signature for this?~~
Author: Andrew Ray <ray.andrew@gmail.com>
Closes#7841 from aray/sql-pivot.
We need to support custom classes like java beans and combine them into tuple, and it's very hard to do it with the TypeTag-based approach.
We should keep only the compose-based way to create tuple encoder.
This PR also move `Encoder` to `org.apache.spark.sql`
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9567 from cloud-fan/java.
This PR is a 2nd follow-up for [SPARK-9241](https://issues.apache.org/jira/browse/SPARK-9241). It contains the following improvements:
* Fix for a potential bug in distinct child expression and attribute alignment.
* Improved handling of duplicate distinct child expressions.
* Added test for distinct UDAF with multiple children.
cc yhuai
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#9566 from hvanhovell/SPARK-9241-followup-2.
This patch adds the building blocks for codegening subexpr elimination and implements
it end to end for UnsafeProjection. The building blocks can be used to do the same thing
for other operators.
It introduces some utilities to compute common sub expressions. Expressions can be added to
this data structure. The expr and its children will be recursively matched against existing
expressions (ones previously added) and grouped into common groups. This is built using
the existing `semanticEquals`. It does not understand things like commutative or associative
expressions. This can be done as future work.
After building this data structure, the codegen process takes advantage of it by:
1. Generating a helper function in the generated class that computes the common
subexpression. This is done for all common subexpressions that have at least
two occurrences and the expression tree is sufficiently complex.
2. When generating the apply() function, if the helper function exists, call that
instead of regenerating the expression tree. Repeated calls to the helper function
shortcircuit the evaluation logic.
Author: Nong Li <nong@databricks.com>
Author: Nong Li <nongli@gmail.com>
This patch had conflicts when merged, resolved by
Committer: Michael Armbrust <michael@databricks.com>
Closes#9480 from nongli/spark-10371.
Currently the user facing api for typed aggregation has some limitations:
* the customized typed aggregation must be the first of aggregation list
* the customized typed aggregation can only use long as buffer type
* the customized typed aggregation can only use flat type as result type
This PR tries to remove these limitations.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9599 from cloud-fan/agg.
https://issues.apache.org/jira/browse/SPARK-9830
This PR contains the following main changes.
* Removing `AggregateExpression1`.
* Removing `Aggregate` operator, which is used to evaluate `AggregateExpression1`.
* Removing planner rule used to plan `Aggregate`.
* Linking `MultipleDistinctRewriter` to analyzer.
* Renaming `AggregateExpression2` to `AggregateExpression` and `AggregateFunction2` to `AggregateFunction`.
* Updating places where we create aggregate expression. The way to create aggregate expressions is `AggregateExpression(aggregateFunction, mode, isDistinct)`.
* Changing `val`s in `DeclarativeAggregate`s that touch children of this function to `lazy val`s (when we create aggregate expression in DataFrame API, children of an aggregate function can be unresolved).
Author: Yin Huai <yhuai@databricks.com>
Closes#9556 from yhuai/removeAgg1.
A few changes:
1. Removed fold, since it can be confusing for distributed collections.
2. Created specific interfaces for each Dataset function (e.g. MapFunction, ReduceFunction, MapPartitionsFunction)
3. Added more documentation and test cases.
The other thing I'm considering doing is to have a "collector" interface for FlatMapFunction and MapPartitionsFunction, similar to MapReduce's map function.
Author: Reynold Xin <rxin@databricks.com>
Closes#9531 from rxin/SPARK-11564.
This PR adds support for multiple column in a single count distinct aggregate to the new aggregation path.
cc yhuai
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#9409 from hvanhovell/SPARK-11451.
This PR is a follow up for PR https://github.com/apache/spark/pull/9406. It adds more documentation to the rewriting rule, removes a redundant if expression in the non-distinct aggregation path and adds a multiple distinct test to the AggregationQuerySuite.
cc yhuai marmbrus
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#9541 from hvanhovell/SPARK-9241-followup.
The second PR for SPARK-9241, this adds support for multiple distinct columns to the new aggregation code path.
This PR solves the multiple DISTINCT column problem by rewriting these Aggregates into an Expand-Aggregate-Aggregate combination. See the [JIRA ticket](https://issues.apache.org/jira/browse/SPARK-9241) for some information on this. The advantages over the - competing - [first PR](https://github.com/apache/spark/pull/9280) are:
- This can use the faster TungstenAggregate code path.
- It is impossible to OOM due to an ```OpenHashSet``` allocating to much memory. However, this will multiply the number of input rows by the number of distinct clauses (plus one), and puts a lot more memory pressure on the aggregation code path itself.
The location of this Rule is a bit funny, and should probably change when the old aggregation path is changed.
cc yhuai - Could you also tell me where to add tests for this?
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#9406 from hvanhovell/SPARK-9241-rewriter.
This PR enables the Expand operator to process and produce Unsafe Rows.
Author: Herman van Hovell <hvanhovell@questtec.nl>
Closes#9414 from hvanhovell/SPARK-11450.
https://issues.apache.org/jira/browse/SPARK-10116
This is really trivial, just happened to notice it -- if `XORShiftRandom.hashSeed` is really supposed to have random bits throughout (as the comment implies), it needs to do something for the conversion to `long`.
mengxr mkolod
Author: Imran Rashid <irashid@cloudera.com>
Closes#8314 from squito/SPARK-10116.
JIRA: https://issues.apache.org/jira/browse/SPARK-9162
Currently ScalaUDF extends CodegenFallback and doesn't provide code generation implementation. This path implements code generation for ScalaUDF.
Author: Liang-Chi Hsieh <viirya@appier.com>
Closes#9270 from viirya/scalaudf-codegen.
A cleanup for https://github.com/apache/spark/pull/9085.
The `DecimalLit` is very similar to `FloatLit`, we can just keep one of them.
Also added low level unit test at `SqlParserSuite`
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9482 from cloud-fan/parser.
This PR adds the ability to do typed SQL aggregations. We will likely also want to provide an interface to allow users to do aggregations on objects, but this is deferred to another PR.
```scala
val ds = Seq(("a", 10), ("a", 20), ("b", 1), ("b", 2), ("c", 1)).toDS()
ds.groupBy(_._1).agg(sum("_2").as[Int]).collect()
res0: Array(("a", 30), ("b", 3), ("c", 1))
```
Author: Michael Armbrust <michael@databricks.com>
Closes#9499 from marmbrus/dataset-agg.
Currently, if the Timestamp is before epoch (1970/01/01), the hours, minutes and seconds will be negative (also rounding up).
Author: Davies Liu <davies@databricks.com>
Closes#9502 from davies/neg_hour.
functions.scala was getting pretty long. I broke it into multiple files.
I also added explicit data types for some public vals, and renamed aggregate function pretty names to lower case, which is more consistent with rest of the functions.
Author: Reynold Xin <rxin@databricks.com>
Closes#9471 from rxin/SPARK-11505.
stddev is an alias for stddev_samp. variance should be consistent with stddev.
Also took the chance to remove internal Stddev and Variance, and only kept StddevSamp/StddevPop and VarianceSamp/VariancePop.
Author: Reynold Xin <rxin@databricks.com>
Closes#9449 from rxin/SPARK-11490.
Right now, SQL's mutable projection updates every value of the mutable project after it evaluates the corresponding expression. This makes the behavior of MutableProjection confusing and complicate the implementation of common aggregate functions like stddev because developers need to be aware that when evaluating {{i+1}}th expression of a mutable projection, {{i}}th slot of the mutable row has already been updated.
This PR make the MutableProjection atomic, by generating all the results of expressions first, then copy them into mutableRow.
Had run a mircro-benchmark, there is no notable performance difference between using class members and local variables.
cc yhuai
Author: Davies Liu <davies@databricks.com>
Closes#9422 from davies/atomic_mutable and squashes the following commits:
bbc1758 [Davies Liu] support wide table
8a0ae14 [Davies Liu] fix bug
bec07da [Davies Liu] refactor
2891628 [Davies Liu] make mutableProjection atomic
Hive GenericUDTF#initialize() defines field names in a returned schema though,
the current HiveGenericUDTF drops these names.
We might need to reflect these in a logical plan tree.
Author: navis.ryu <navis@apache.org>
Closes#8456 from navis/SPARK-9034.
1. Supporting expanding structs in Projections. i.e.
"SELECT s.*" where s is a struct type.
This is fixed by allowing the expand function to handle structs in addition to tables.
2. Supporting expanding * inside aggregate functions of structs.
"SELECT max(struct(col1, structCol.*))"
This requires recursively expanding the expressions. In this case, it it the aggregate
expression "max(...)" and we need to recursively expand its children inputs.
Author: Nong Li <nongli@gmail.com>
Closes#9343 from nongli/spark-11329.
From Reynold in the thread 'Exception when using some aggregate operators' (http://search-hadoop.com/m/q3RTt0xFr22nXB4/):
I don't think these are bugs. The SQL standard for average is "avg", not "mean". Similarly, a distinct count is supposed to be written as "count(distinct col)", not "countDistinct(col)".
We can, however, make "mean" an alias for "avg" to improve compatibility between DataFrame and SQL.
Author: tedyu <yuzhihong@gmail.com>
Closes#9332 from ted-yu/master.
JIRA: https://issues.apache.org/jira/browse/SPARK-9298
This patch adds pearson correlation aggregation function based on `AggregateExpression2`.
Author: Liang-Chi Hsieh <viirya@appier.com>
Closes#8587 from viirya/corr_aggregation.
DISTRIBUTE BY allows the user to hash partition the data by specified exprs. It also allows for
optioning sorting within each resulting partition. There is no required relationship between the
exprs for partitioning and sorting (i.e. one does not need to be a prefix of the other).
This patch adds to APIs to DataFrames which can be used together to provide this functionality:
1. distributeBy() which partitions the data frame into a specified number of partitions using the
partitioning exprs.
2. localSort() which sorts each partition using the provided sorting exprs.
To get the DISTRIBUTE BY functionality, the user simply does: df.distributeBy(...).localSort(...)
Author: Nong Li <nongli@gmail.com>
Closes#9364 from nongli/spark-11410.
Add a rule in optimizer to convert NULL [NOT] IN (expr1,...,expr2) to
Literal(null).
This is a follow up defect to SPARK-8654
cloud-fan Can you please take a look ?
Author: Dilip Biswal <dbiswal@us.ibm.com>
Closes#9348 from dilipbiswal/spark_11024.
Older version of Janino (>2.7) does not support Override, we should not use that in codegen.
Author: Davies Liu <davies@databricks.com>
Closes#9372 from davies/no_override.
This PR introduce a mechanism to call spill() on those SQL operators that support spilling (for example, BytesToBytesMap, UnsafeExternalSorter and ShuffleExternalSorter) if there is not enough memory for execution. The preserved first page is needed anymore, so removed.
Other Spillable objects in Spark core (ExternalSorter and AppendOnlyMap) are not included in this PR, but those could benefit from this (trigger others' spilling).
The PrepareRDD may be not needed anymore, could be removed in follow up PR.
The following script will fail with OOM before this PR, finished in 150 seconds with 2G heap (also works in 1.5 branch, with similar duration).
```python
sqlContext.setConf("spark.sql.shuffle.partitions", "1")
df = sqlContext.range(1<<25).selectExpr("id", "repeat(id, 2) as s")
df2 = df.select(df.id.alias('id2'), df.s.alias('s2'))
j = df.join(df2, df.id==df2.id2).groupBy(df.id).max("id", "id2")
j.explain()
print j.count()
```
For thread-safety, here what I'm got:
1) Without calling spill(), the operators should only be used by single thread, no safety problems.
2) spill() could be triggered in two cases, triggered by itself, or by other operators. we can check trigger == this in spill(), so it's still in the same thread, so safety problems.
3) if it's triggered by other operators (right now cache will not trigger spill()), we only spill the data into disk when it's in scanning stage (building is finished), so the in-memory sorter or memory pages are read-only, we only need to synchronize the iterator and change it.
4) During scanning, the iterator will only use one record in one page, we can't free this page, because the downstream is currently using it (used by UnsafeRow or other objects). In BytesToBytesMap, we just skip the current page, and dump all others into disk. In UnsafeExternalSorter, we keep the page that is used by current record (having the same baseObject), free it when loading the next record. In ShuffleExternalSorter, the spill() will not trigger during scanning.
5) In order to avoid deadlock, we didn't call acquireMemory during spill (so we reused the pointer array in InMemorySorter).
Author: Davies Liu <davies@databricks.com>
Closes#9241 from davies/force_spill.
This is minor, but I ran into while writing Datasets and while it wasn't needed for the final solution, it was super confusing so we should fix it.
Basically we recurse into `Seq` to see if they have children. This breaks because we don't preserve the original subclass of `Seq` (and `StructType <:< Seq[StructField]`). Since a struct can never contain children, lets just not recurse into it.
Author: Michael Armbrust <michael@databricks.com>
Closes#9334 from marmbrus/structMakeCopy.
This PR adds a new operation `joinWith` to a `Dataset`, which returns a `Tuple` for each pair where a given `condition` evaluates to true.
```scala
case class ClassData(a: String, b: Int)
val ds1 = Seq(ClassData("a", 1), ClassData("b", 2)).toDS()
val ds2 = Seq(("a", 1), ("b", 2)).toDS()
> ds1.joinWith(ds2, $"_1" === $"a").collect()
res0: Array((ClassData("a", 1), ("a", 1)), (ClassData("b", 2), ("b", 2)))
```
This operation is similar to the relation `join` function with one important difference in the result schema. Since `joinWith` preserves objects present on either side of the join, the result schema is similarly nested into a tuple under the column names `_1` and `_2`.
This type of join can be useful both for preserving type-safety with the original object types as well as working with relational data where either side of the join has column names in common.
## Required Changes to Encoders
In the process of working on this patch, several deficiencies to the way that we were handling encoders were discovered. Specifically, it turned out to be very difficult to `rebind` the non-expression based encoders to extract the nested objects from the results of joins (and also typed selects that return tuples).
As a result the following changes were made.
- `ClassEncoder` has been renamed to `ExpressionEncoder` and has been improved to also handle primitive types. Additionally, it is now possible to take arbitrary expression encoders and rewrite them into a single encoder that returns a tuple.
- All internal operations on `Dataset`s now require an `ExpressionEncoder`. If the users tries to pass a non-`ExpressionEncoder` in, an error will be thrown. We can relax this requirement in the future by constructing a wrapper class that uses expressions to project the row to the expected schema, shielding the users code from the required remapping. This will give us a nice balance where we don't force user encoders to understand attribute references and binding, but still allow our native encoder to leverage runtime code generation to construct specific encoders for a given schema that avoid an extra remapping step.
- Additionally, the semantics for different types of objects are now better defined. As stated in the `ExpressionEncoder` scaladoc:
- Classes will have their sub fields extracted by name using `UnresolvedAttribute` expressions
and `UnresolvedExtractValue` expressions.
- Tuples will have their subfields extracted by position using `BoundReference` expressions.
- Primitives will have their values extracted from the first ordinal with a schema that defaults
to the name `value`.
- Finally, the binding lifecycle for `Encoders` has now been unified across the codebase. Encoders are now `resolved` to the appropriate schema in the constructor of `Dataset`. This process replaces an unresolved expressions with concrete `AttributeReference` expressions. Binding then happens on demand, when an encoder is going to be used to construct an object. This closely mirrors the lifecycle for standard expressions when executing normal SQL or `DataFrame` queries.
Author: Michael Armbrust <michael@databricks.com>
Closes#9300 from marmbrus/datasets-tuples.
When sampling and then filtering DataFrame, the SQL Optimizer will push down filter into sample and produce wrong result. This is due to the sampler is calculated based on the original scope rather than the scope after filtering.
Author: Yanbo Liang <ybliang8@gmail.com>
Closes#9294 from yanboliang/spark-11303.
I'm new to spark. I was trying out the sort_array function then hit this exception. I looked into the spark source code. I found the root cause is that sort_array does not check for an array of NULLs. It's not meaningful to sort an array of entirely NULLs anyway.
I'm adding a check on the input array type to SortArray. If the array consists of NULLs entirely, there is no need to sort such array. I have also added a test case for this.
Please help to review my fix. Thanks!
Author: Jia Li <jiali@us.ibm.com>
Closes#9247 from jliwork/SPARK-11277.
This patch refactors the MemoryManager class structure. After #9000, Spark had the following classes:
- MemoryManager
- StaticMemoryManager
- ExecutorMemoryManager
- TaskMemoryManager
- ShuffleMemoryManager
This is fairly confusing. To simplify things, this patch consolidates several of these classes:
- ShuffleMemoryManager and ExecutorMemoryManager were merged into MemoryManager.
- TaskMemoryManager is moved into Spark Core.
**Key changes and tasks**:
- [x] Merge ExecutorMemoryManager into MemoryManager.
- [x] Move pooling logic into Allocator.
- [x] Move TaskMemoryManager from `spark-unsafe` to `spark-core`.
- [x] Refactor the existing Tungsten TaskMemoryManager interactions so Tungsten code use only this and not both this and ShuffleMemoryManager.
- [x] Refactor non-Tungsten code to use the TaskMemoryManager instead of ShuffleMemoryManager.
- [x] Merge ShuffleMemoryManager into MemoryManager.
- [x] Move code
- [x] ~~Simplify 1/n calculation.~~ **Will defer to followup, since this needs more work.**
- [x] Port ShuffleMemoryManagerSuite tests.
- [x] Move classes from `unsafe` package to `memory` package.
- [ ] Figure out how to handle the hacky use of the memory managers in HashedRelation's broadcast variable construction.
- [x] Test porting and cleanup: several tests relied on mock functionality (such as `TestShuffleMemoryManager.markAsOutOfMemory`) which has been changed or broken during the memory manager consolidation
- [x] AbstractBytesToBytesMapSuite
- [x] UnsafeExternalSorterSuite
- [x] UnsafeFixedWidthAggregationMapSuite
- [x] UnsafeKVExternalSorterSuite
**Compatiblity notes**:
- This patch introduces breaking changes in `ExternalAppendOnlyMap`, which is marked as `DevloperAPI` (likely for legacy reasons): this class now cannot be used outside of a task.
Author: Josh Rosen <joshrosen@databricks.com>
Closes#9127 from JoshRosen/SPARK-10984.
marmbrus rxin I believe these typecasts are not required in the presence of explicit return types.
Author: Alexander Slesarenko <avslesarenko@gmail.com>
Closes#9262 from aslesarenko/remove-typecasts.
For nested StructType, the underline buffer could be used for others before, we should zero out the padding bytes for those primitive types that have less than 8 bytes.
cc cloud-fan
Author: Davies Liu <davies@databricks.com>
Closes#9217 from davies/zero_out.
*This PR adds a new experimental API to Spark, tentitively named Datasets.*
A `Dataset` is a strongly-typed collection of objects that can be transformed in parallel using functional or relational operations. Example usage is as follows:
### Functional
```scala
> val ds: Dataset[Int] = Seq(1, 2, 3).toDS()
> ds.filter(_ % 1 == 0).collect()
res1: Array[Int] = Array(1, 2, 3)
```
### Relational
```scala
scala> ds.toDF().show()
+-----+
|value|
+-----+
| 1|
| 2|
| 3|
+-----+
> ds.select(expr("value + 1").as[Int]).collect()
res11: Array[Int] = Array(2, 3, 4)
```
## Comparison to RDDs
A `Dataset` differs from an `RDD` in the following ways:
- The creation of a `Dataset` requires the presence of an explicit `Encoder` that can be
used to serialize the object into a binary format. Encoders are also capable of mapping the
schema of a given object to the Spark SQL type system. In contrast, RDDs rely on runtime
reflection based serialization.
- Internally, a `Dataset` is represented by a Catalyst logical plan and the data is stored
in the encoded form. This representation allows for additional logical operations and
enables many operations (sorting, shuffling, etc.) to be performed without deserializing to
an object.
A `Dataset` can be converted to an `RDD` by calling the `.rdd` method.
## Comparison to DataFrames
A `Dataset` can be thought of as a specialized DataFrame, where the elements map to a specific
JVM object type, instead of to a generic `Row` container. A DataFrame can be transformed into
specific Dataset by calling `df.as[ElementType]`. Similarly you can transform a strongly-typed
`Dataset` to a generic DataFrame by calling `ds.toDF()`.
## Implementation Status and TODOs
This is a rough cut at the least controversial parts of the API. The primary purpose here is to get something committed so that we can better parallelize further work and get early feedback on the API. The following is being deferred to future PRs:
- Joins and Aggregations (prototype here f11f91e6f0)
- Support for Java
Additionally, the responsibility for binding an encoder to a given schema is currently done in a fairly ad-hoc fashion. This is an internal detail, and what we are doing today works for the cases we care about. However, as we add more APIs we'll probably need to do this in a more principled way (i.e. separate resolution from binding as we do in DataFrames).
## COMPATIBILITY NOTE
Long term we plan to make `DataFrame` extend `Dataset[Row]`. However,
making this change to che class hierarchy would break the function signatures for the existing
function operations (map, flatMap, etc). As such, this class should be considered a preview
of the final API. Changes will be made to the interface after Spark 1.6.
Author: Michael Armbrust <michael@databricks.com>
Closes#9190 from marmbrus/dataset-infra.
This PR change InMemoryTableScan to output UnsafeRow, and optimize the unrolling and scanning by coping the bytes for var-length types between UnsafeRow and ByteBuffer directly without creating the wrapper objects. When scanning the decimals in TPC-DS store_sales table, it's 80% faster (copy it as long without create Decimal objects).
Author: Davies Liu <davies@databricks.com>
Closes#9203 from davies/unsafe_cache.
In the analysis phase , while processing the rules for IN predicate, we
compare the in-list types to the lhs expression type and generate
cast operation if necessary. In the case of NULL [NOT] IN expr1 , we end up
generating cast between in list types to NULL like cast (1 as NULL) which
is not a valid cast.
The fix is to find a common type between LHS and RHS expressions and cast
all the expression to the common type.
Author: Dilip Biswal <dbiswal@us.ibm.com>
This patch had conflicts when merged, resolved by
Committer: Michael Armbrust <michael@databricks.com>
Closes#9036 from dilipbiswal/spark_8654_new.
I am changing the default behavior of `First`/`Last` to respect null values (the SQL standard default behavior).
https://issues.apache.org/jira/browse/SPARK-9740
Author: Yin Huai <yhuai@databricks.com>
Closes#8113 from yhuai/firstLast.
This PR introduce a new feature to run SQL directly on files without create a table, for example:
```
select id from json.`path/to/json/files` as j
```
Author: Davies Liu <davies@databricks.com>
Closes#9173 from davies/source.
Find out the missing attributes by recursively looking
at the sort order expression and rest of the code
takes care of projecting them out.
Added description from cloud-fan
I wanna explain a bit more about this bug.
When we resolve sort ordering, we will use a special method, which only resolves UnresolvedAttributes and UnresolvedExtractValue. However, for something like Floor('a), even the 'a is resolved, the floor expression may still being unresolved as data type mismatch(for example, 'a is string type and Floor need double type), thus can't pass this filter, and we can't push down this missing attribute 'a
Author: Dilip Biswal <dbiswal@us.ibm.com>
Closes#9123 from dilipbiswal/SPARK-10534.
Implement encode/decode for external row based on `ClassEncoder`.
TODO:
* code cleanup
* ~~fix corner cases~~
* refactor the encoder interface
* improve test for product codegen, to cover more corner cases.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9184 from cloud-fan/encoder.
Push conjunctive predicates though Aggregate operators when their references are a subset of the groupingExpressions.
Query plan before optimisation :-
Filter ((c#138L = 2) && (a#0 = 3))
Aggregate [a#0], [a#0,count(b#1) AS c#138L]
Project [a#0,b#1]
LocalRelation [a#0,b#1,c#2]
Query plan after optimisation :-
Filter (c#138L = 2)
Aggregate [a#0], [a#0,count(b#1) AS c#138L]
Filter (a#0 = 3)
Project [a#0,b#1]
LocalRelation [a#0,b#1,c#2]
Author: nitin goyal <nitin.goyal@guavus.com>
Author: nitin.goyal <nitin.goyal@guavus.com>
Closes#9167 from nitin2goyal/master.
This PR improve the performance by:
1) Generate an Iterator that take Iterator[CachedBatch] as input, and call accessors (unroll the loop for columns), avoid the expensive Iterator.flatMap.
2) Use Unsafe.getInt/getLong/getFloat/getDouble instead of ByteBuffer.getInt/getLong/getFloat/getDouble, the later one actually read byte by byte.
3) Remove the unnecessary copy() in Coalesce(), which is not related to memory cache, found during benchmark.
The following benchmark showed that we can speedup the columnar cache of int by 2x.
```
path = '/opt/tpcds/store_sales/'
int_cols = ['ss_sold_date_sk', 'ss_sold_time_sk', 'ss_item_sk','ss_customer_sk']
df = sqlContext.read.parquet(path).select(int_cols).cache()
df.count()
t = time.time()
print df.select("*")._jdf.queryExecution().toRdd().count()
print time.time() - t
```
Author: Davies Liu <davies@databricks.com>
Closes#9145 from davies/byte_buffer.
Currently, we use CartesianProduct for join with null-safe-equal condition.
```
scala> sqlContext.sql("select * from t a join t b on (a.i <=> b.i)").explain
== Physical Plan ==
TungstenProject [i#2,j#3,i#7,j#8]
Filter (i#2 <=> i#7)
CartesianProduct
LocalTableScan [i#2,j#3], [[1,1]]
LocalTableScan [i#7,j#8], [[1,1]]
```
Actually, we can have an equal-join condition as `coalesce(i, default) = coalesce(b.i, default)`, then an partitioned join algorithm could be used.
After this PR, the plan will become:
```
>>> sqlContext.sql("select * from a join b ON a.id <=> b.id").explain()
TungstenProject [id#0L,id#1L]
Filter (id#0L <=> id#1L)
SortMergeJoin [coalesce(id#0L,0)], [coalesce(id#1L,0)]
TungstenSort [coalesce(id#0L,0) ASC], false, 0
TungstenExchange hashpartitioning(coalesce(id#0L,0),200)
ConvertToUnsafe
Scan PhysicalRDD[id#0L]
TungstenSort [coalesce(id#1L,0) ASC], false, 0
TungstenExchange hashpartitioning(coalesce(id#1L,0),200)
ConvertToUnsafe
Scan PhysicalRDD[id#1L]
```
Author: Davies Liu <davies@databricks.com>
Closes#9120 from davies/null_safe.
We can't parse `NOT` operator with comparison operations like `SELECT NOT TRUE > TRUE`, this PR fixed it.
Takes over https://github.com/apache/spark/pull/6326.
Author: Wenchen Fan <cloud0fan@outlook.com>
Closes#8617 from cloud-fan/not.
The purpose of this PR is to keep the unsafe format detail only inside the unsafe class itself, so when we use them(like use unsafe array in unsafe map, use unsafe array and map in columnar cache), we don't need to understand the format before use them.
change list:
* unsafe array's 4-bytes numElements header is now required(was optional), and become a part of unsafe array format.
* w.r.t the previous changing, the `sizeInBytes` of unsafe array now counts the 4-bytes header.
* unsafe map's format was `[numElements] [key array numBytes] [key array content(without numElements header)] [value array content(without numElements header)]` before, which is a little hacky as it makes unsafe array's header optional. I think saving 4 bytes is not a big deal, so the format is now: `[key array numBytes] [unsafe key array] [unsafe value array]`.
* w.r.t the previous changing, the `sizeInBytes` of unsafe map now counts both map's header and array's header.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9131 from cloud-fan/unsafe.
