For now they are thin wrappers around the corresponding Hive UDAFs.
One limitation with these in Hive 0.13.0 is they only support aggregating primitive types.
I chose snake_case here instead of camelCase because it seems to be used in the majority of the multi-word fns.
Do we also want to add these to `functions.py`?
This approach was recommended here: https://github.com/apache/spark/pull/8592#issuecomment-154247089
marmbrus rxin
Author: Nick Buroojy <nick.buroojy@civitaslearning.com>
Closes#9526 from nburoojy/nick/udaf-alias.
(cherry picked from commit a6ee4f989d)
Signed-off-by: Michael Armbrust <michael@databricks.com>
The reason is that:
1. For partitioned hive table, we will move the partitioned columns after data columns. (e.g. `<a: Int, b: Int>` partition by `a` will become `<b: Int, a: Int>`)
2. When append data to table, we use position to figure out how to match input columns to table's columns.
So when we append data to partitioned table, we will match wrong columns between input and table. A solution is reordering the input columns before match by position, like what we did for [`InsertIntoHadoopFsRelation`](https://github.com/apache/spark/blob/master/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/InsertIntoHadoopFsRelation.scala#L101-L105)
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9408 from cloud-fan/append.
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.
JIRA: https://issues.apache.org/jira/browse/SPARK-11362
We use scala.collection.mutable.BitSet in BroadcastNestedLoopJoin now. We should use Spark's BitSet.
Author: Liang-Chi Hsieh <viirya@appier.com>
Closes#9316 from viirya/use-spark-bitset.
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.
This PR adds test cases that test various column pruning and filter push-down cases.
Author: Cheng Lian <lian@databricks.com>
Closes#9468 from liancheng/spark-10978.follow-up.
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.
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.
This brings the support of off-heap memory for array inside BytesToBytesMap and InMemorySorter, then we could allocate all the memory from off-heap for execution.
Closes#8068
Author: Davies Liu <davies@databricks.com>
Closes#9477 from davies/unsafe_timsort.
the main problem is: we interpret column name with special handling of `.` for DataFrame. This enables us to write something like `df("a.b")` to get the field `b` of `a`. However, we don't need this feature in `DataFrame.apply("*")` or `DataFrame.withColumnRenamed`. In these 2 cases, the column name is the final name already, we don't need extra process to interpret it.
The solution is simple, use `queryExecution.analyzed.output` to get resolved column directly, instead of using `DataFrame.resolve`.
close https://github.com/apache/spark/pull/8811
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9462 from cloud-fan/special-chars.
This is the alternative/agreed upon solution to PR #8780.
Creating an OracleDialect to handle the nonspecific numeric types that can be defined in oracle.
Author: Travis Hegner <thegner@trilliumit.com>
Closes#9495 from travishegner/OracleDialect.
This internal implicit conversion has been a source of confusion for a lot of new developers.
Author: Reynold Xin <rxin@databricks.com>
Closes#9479 from rxin/SPARK-11513.
In DefaultDataSource.scala, it has
override def createRelation(
sqlContext: SQLContext,
parameters: Map[String, String]): BaseRelation
The parameters is CaseInsensitiveMap.
After this line
parameters.foreach(kv => properties.setProperty(kv._1, kv._2))
properties is set to all lower case key/value pairs and fetchSize becomes fetchsize.
However, in compute method in JDBCRDD, it has
val fetchSize = properties.getProperty("fetchSize", "0").toInt
so fetchSize value is always 0 and never gets set correctly.
Author: Huaxin Gao <huaxing@oc0558782468.ibm.com>
Closes#9473 from huaxingao/spark-11474.
After aggregation, the dataset could be smaller than inputs, so it's better to do hash based aggregation for all inputs, then using sort based aggregation to merge them.
Author: Davies Liu <davies@databricks.com>
Closes#9383 from davies/fix_switch.
1. def dialectClassName in HiveContext is unnecessary.
In HiveContext, if conf.dialect == "hiveql", getSQLDialect() will return new HiveQLDialect(this);
else it will use super.getSQLDialect(). Then in super.getSQLDialect(), it calls dialectClassName, which is overriden in HiveContext and still return super.dialectClassName.
So we'll never reach the code "classOf[HiveQLDialect].getCanonicalName" of def dialectClassName in HiveContext.
2. When we start bin/spark-sql, the default context is HiveContext, and the corresponding dialect is hiveql.
However, if we type "set spark.sql.dialect;", the result is "sql", which is inconsistent with the actual dialect and is misleading. For example, we can use sql like "create table" which is only allowed in hiveql, but this dialect conf shows it's "sql".
Although this problem will not cause any execution error, it's misleading to spark sql users. Therefore I think we should fix it.
In this pr, while procesing “set spark.sql.dialect” in SetCommand, I use "conf.dialect" instead of "getConf()" for the case of key == SQLConf.DIALECT.key, so that it will return the right dialect conf.
Author: Zhenhua Wang <wangzhenhua@huawei.com>
Closes#9349 from wzhfy/dialect.
We have some aggregate function tests in both DataFrameAggregateSuite and SQLQuerySuite. The two have almost the same coverage and we should just remove the SQL one.
Author: Reynold Xin <rxin@databricks.com>
Closes#9475 from rxin/SPARK-11510.
1. Renamed localSort -> sortWithinPartitions to avoid ambiguity in "local"
2. distributeBy -> repartition to match the existing repartition.
Author: Reynold Xin <rxin@databricks.com>
Closes#9470 from rxin/SPARK-11504.
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.
depend on `caseSensitive` to do column name equality check, instead of just `==`
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9410 from cloud-fan/partition.
We added a bunch of higher order statistics such as skewness and kurtosis to GroupedData. I don't think they are common enough to justify being listed, since users can always use the normal statistics aggregate functions.
That is to say, after this change, we won't support
```scala
df.groupBy("key").kurtosis("colA", "colB")
```
However, we will still support
```scala
df.groupBy("key").agg(kurtosis(col("colA")), kurtosis(col("colB")))
```
Author: Reynold Xin <rxin@databricks.com>
Closes#9446 from rxin/SPARK-11489.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9434 from cloud-fan/rdd2ds and squashes the following commits:
0892d72 [Wenchen Fan] support create Dataset from RDD
Add Python API for stddev/stddev_pop/stddev_samp/variance/var_pop/var_samp/skewness/kurtosis
Author: Davies Liu <davies@databricks.com>
Closes#9424 from davies/py_var.
This PR adds a new method `unhandledFilters` to `BaseRelation`. Data sources which implement this method properly may avoid the overhead of defensive filtering done by Spark SQL.
Author: Cheng Lian <lian@databricks.com>
Closes#9399 from liancheng/spark-10978.unhandled-filters.
JIRA: https://issues.apache.org/jira/browse/SPARK-10304
This patch detects if the structure of partition directories is not valid.
The test cases are from #8547. Thanks zhzhan.
cc liancheng
Author: Liang-Chi Hsieh <viirya@appier.com>
Closes#8840 from viirya/detect_invalid_part_dir.
This PR adds a new method `groupBy(cols: Column*)` to `Dataset` that allows users to group using column expressions instead of a lambda function. Since the return type of these expressions is not known at compile time, we just set the key type as a generic `Row`. If the user would like to work the key in a type-safe way, they can call `grouped.asKey[Type]`, which is also added in this PR.
```scala
val ds = Seq(("a", 10), ("a", 20), ("b", 1), ("b", 2), ("c", 1)).toDS()
val grouped = ds.groupBy($"_1").asKey[String]
val agged = grouped.mapGroups { case (g, iter) =>
Iterator((g, iter.map(_._2).sum))
}
agged.collect()
res0: Array(("a", 30), ("b", 3), ("c", 1))
```
Author: Michael Armbrust <michael@databricks.com>
Closes#9359 from marmbrus/columnGroupBy and squashes the following commits:
bbcb03b [Michael Armbrust] Update DatasetSuite.scala
8fd2908 [Michael Armbrust] Update DatasetSuite.scala
0b0e2f8 [Michael Armbrust] [SPARK-11404] [SQL] Support for groupBy using column expressions
When we join 2 datasets, we will combine 2 encoders into a tupled one, and use it as the encoder for the jioned dataset. Assume both of the 2 encoders are flat, their `constructExpression`s both reference to the first element of input row. However, when we combine 2 encoders, the schema of input row changed, now the right encoder should reference to second element of input row. So we should rebind right encoder to let it know the new schema of input row before combine it.
Author: Wenchen Fan <wenchen@databricks.com>
Closes#9391 from cloud-fan/join and squashes the following commits:
846d3ab [Wenchen Fan] rebind right encoder when join 2 datasets
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.
…ering.
For cached tables, we can just maintain the partitioning and ordering from the
source relation.
Author: Nong Li <nongli@gmail.com>
Closes#9404 from nongli/spark-5354.
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.
This PR fixes two issues:
1. `PhysicalRDD.outputsUnsafeRows` is always `false`
Thus a `ConvertToUnsafe` operator is often required even if the underlying data source relation does output `UnsafeRow`.
1. Internal/external row conversion for `HadoopFsRelation` is kinda messy
Currently we're using `HadoopFsRelation.needConversion` and [dirty type erasure hacks][1] to indicate whether the relation outputs external row or internal row and apply external-to-internal conversion when necessary. Basically, all builtin `HadoopFsRelation` data sources, i.e. Parquet, JSON, ORC, and Text output `InternalRow`, while typical external `HadoopFsRelation` data sources, e.g. spark-avro and spark-csv, output `Row`.
This PR adds a `private[sql]` interface method `HadoopFsRelation.buildInternalScan`, which by default invokes `HadoopFsRelation.buildScan` and converts `Row`s to `UnsafeRow`s (which are also `InternalRow`s). All builtin `HadoopFsRelation` data sources override this method and directly output `UnsafeRow`s. In this way, now `HadoopFsRelation` always produces `UnsafeRow`s. Thus `PhysicalRDD.outputsUnsafeRows` can be properly set by checking whether the underlying data source is a `HadoopFsRelation`.
A remaining question is that, can we assume that all non-builtin `HadoopFsRelation` data sources output external rows? At least all well known ones do so. However it's possible that some users implemented their own `HadoopFsRelation` data sources that leverages `InternalRow` and thus all those unstable internal data representations. If this assumption is safe, we can deprecate `HadoopFsRelation.needConversion` and cleanup some more conversion code (like [here][2] and [here][3]).
This PR supersedes #9125.
Follow-ups:
1. Makes JSON and ORC data sources output `UnsafeRow` directly
1. Makes `HiveTableScan` output `UnsafeRow` directly
This is related to 1 since ORC data source shares the same `Writable` unwrapping code with `HiveTableScan`.
[1]: https://github.com/apache/spark/blob/v1.5.1/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/parquet/ParquetRelation.scala#L353
[2]: https://github.com/apache/spark/blob/v1.5.1/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/DataSourceStrategy.scala#L331-L335
[3]: https://github.com/apache/spark/blob/v1.5.1/sql/core/src/main/scala/org/apache/spark/sql/sources/interfaces.scala#L630-L669
Author: Cheng Lian <lian@databricks.com>
Closes#9305 from liancheng/spark-11345.unsafe-hadoop-fs-relation.
