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4190 commits

Author SHA1 Message Date
Wenchen Fan 970ab8f6dd [SPARK-17187][SQL][FOLLOW-UP] improve document of TypedImperativeAggregate
## What changes were proposed in this pull request?

improve the document to make it easier to understand and also mention window operator.

## How was this patch tested?

N/A

Author: Wenchen Fan <wenchen@databricks.com>

Closes #14822 from cloud-fan/object-agg.
2016-08-26 10:56:57 -07:00
Wenchen Fan 28ab17922a [SPARK-17260][MINOR] move CreateTables to HiveStrategies
## What changes were proposed in this pull request?

`CreateTables` rule turns a general `CreateTable` plan to `CreateHiveTableAsSelectCommand` for hive serde table. However, this rule is logically a planner strategy, we should move it to `HiveStrategies`, to be consistent with other DDL commands.

## How was this patch tested?

existing tests.

Author: Wenchen Fan <wenchen@databricks.com>

Closes #14825 from cloud-fan/ctas.
2016-08-26 08:52:10 -07:00
hyukjinkwon 6063d5963f [SPARK-16216][SQL][FOLLOWUP] Enable timestamp type tests for JSON and verify all unsupported types in CSV
## What changes were proposed in this pull request?

This PR enables the tests for `TimestampType` for JSON and unifies the logics for verifying schema when writing in CSV.

In more details, this PR,

- Enables the tests for `TimestampType` for JSON and

  This was disabled due to an issue in `DatatypeConverter.parseDateTime` which parses dates incorrectly, for example as below:

  ```scala
   val d = javax.xml.bind.DatatypeConverter.parseDateTime("0900-01-01T00:00:00.000").getTime
  println(d.toString)
  ```
  ```
  Fri Dec 28 00:00:00 KST 899
  ```

  However, since we use `FastDateFormat`, it seems we are safe now.

  ```scala
  val d = FastDateFormat.getInstance("yyyy-MM-dd'T'HH:mm:ss.SSS").parse("0900-01-01T00:00:00.000")
  println(d)
  ```
  ```
  Tue Jan 01 00:00:00 PST 900
  ```

- Verifies all unsupported types in CSV

  There is a separate logics to verify the schemas in `CSVFileFormat`. This is actually not quite correct enough because we don't support `NullType` and `CalanderIntervalType` as well `StructType`, `ArrayType`, `MapType`. So, this PR adds both types.

## How was this patch tested?

Tests in `JsonHadoopFsRelation` and `CSVSuite`

Author: hyukjinkwon <gurwls223@gmail.com>

Closes #14829 from HyukjinKwon/SPARK-16216-followup.
2016-08-26 17:29:37 +02:00
hyukjinkwon b964a172a8 [SPARK-17212][SQL] TypeCoercion supports widening conversion between DateType and TimestampType
## What changes were proposed in this pull request?

Currently, type-widening does not work between `TimestampType` and `DateType`.

This applies to `SetOperation`, `Union`, `In`, `CaseWhen`, `Greatest`,  `Leatest`, `CreateArray`, `CreateMap`, `Coalesce`, `NullIf`, `IfNull`, `Nvl` and `Nvl2`, .

This PR adds the support for widening `DateType` to `TimestampType` for them.

For a simple example,

**Before**

```scala
Seq(Tuple2(new Timestamp(0), new Date(0))).toDF("a", "b").selectExpr("greatest(a, b)").show()
```

shows below:

```
cannot resolve 'greatest(`a`, `b`)' due to data type mismatch: The expressions should all have the same type, got GREATEST(timestamp, date)
```

or union as below:

```scala
val a = Seq(Tuple1(new Timestamp(0))).toDF()
val b = Seq(Tuple1(new Date(0))).toDF()
a.union(b).show()
```

shows below:

```
Union can only be performed on tables with the compatible column types. DateType <> TimestampType at the first column of the second table;
```

**After**

```scala
Seq(Tuple2(new Timestamp(0), new Date(0))).toDF("a", "b").selectExpr("greatest(a, b)").show()
```

shows below:

```
+----------------------------------------------------+
|greatest(CAST(a AS TIMESTAMP), CAST(b AS TIMESTAMP))|
+----------------------------------------------------+
|                                1969-12-31 16:00:...|
+----------------------------------------------------+
```

or union as below:

```scala
val a = Seq(Tuple1(new Timestamp(0))).toDF()
val b = Seq(Tuple1(new Date(0))).toDF()
a.union(b).show()
```

shows below:

```
+--------------------+
|                  _1|
+--------------------+
|1969-12-31 16:00:...|
|1969-12-31 00:00:...|
+--------------------+
```

## How was this patch tested?

Unit tests in `TypeCoercionSuite`.

Author: hyukjinkwon <gurwls223@gmail.com>
Author: HyukjinKwon <gurwls223@gmail.com>

Closes #14786 from HyukjinKwon/SPARK-17212.
2016-08-26 08:58:43 +08:00
Sean Zhong d96d151563 [SPARK-17187][SQL] Supports using arbitrary Java object as internal aggregation buffer object
## What changes were proposed in this pull request?

This PR introduces an abstract class `TypedImperativeAggregate` so that an aggregation function of TypedImperativeAggregate can use  **arbitrary** user-defined Java object as intermediate aggregation buffer object.

**This has advantages like:**
1. It now can support larger category of aggregation functions. For example, it will be much easier to implement aggregation function `percentile_approx`, which has a complex aggregation buffer definition.
2. It can be used to avoid doing serialization/de-serialization for every call of `update` or `merge` when converting domain specific aggregation object to internal Spark-Sql storage format.
3. It is easier to integrate with other existing monoid libraries like algebird, and supports more aggregation functions with high performance.

Please see `org.apache.spark.sql.TypedImperativeAggregateSuite.TypedMaxAggregate` to find an example of how to defined a `TypedImperativeAggregate` aggregation function.
Please see Java doc of `TypedImperativeAggregate` and Jira ticket SPARK-17187 for more information.

## How was this patch tested?

Unit tests.

Author: Sean Zhong <seanzhong@databricks.com>
Author: Yin Huai <yhuai@databricks.com>

Closes #14753 from clockfly/object_aggregation_buffer_try_2.
2016-08-25 16:36:16 -07:00
Josh Rosen 3e4c7db4d1 [SPARK-17205] Literal.sql should handle Infinity and NaN
This patch updates `Literal.sql` to properly generate SQL for `NaN` and `Infinity` float and double literals: these special values need to be handled differently from regular values, since simply appending a suffix to the value's `toString()` representation will not work for these values.

Author: Josh Rosen <joshrosen@databricks.com>

Closes #14777 from JoshRosen/SPARK-17205.
2016-08-26 00:15:01 +02:00
Josh Rosen a133057ce5 [SPARK-17229][SQL] PostgresDialect shouldn't widen float and short types during reads
## What changes were proposed in this pull request?

When reading float4 and smallint columns from PostgreSQL, Spark's `PostgresDialect` widens these types to Decimal and Integer rather than using the narrower Float and Short types. According to https://www.postgresql.org/docs/7.1/static/datatype.html#DATATYPE-TABLE, Postgres maps the `smallint` type to a signed two-byte integer and the `real` / `float4` types to single precision floating point numbers.

This patch fixes this by adding more special-cases to `getCatalystType`, similar to what was done for the Derby JDBC dialect. I also fixed a similar problem in the write path which causes Spark to create integer columns in Postgres for what should have been ShortType columns.

## How was this patch tested?

New test cases in `PostgresIntegrationSuite` (which I ran manually because Jenkins can't run it right now).

Author: Josh Rosen <joshrosen@databricks.com>

Closes #14796 from JoshRosen/postgres-jdbc-type-fixes.
2016-08-25 23:22:40 +02:00
gatorsmile d2ae6399ee [SPARK-16991][SPARK-17099][SPARK-17120][SQL] Fix Outer Join Elimination when Filter's isNotNull Constraints Unable to Filter Out All Null-supplying Rows
### What changes were proposed in this pull request?
This PR is to fix an incorrect outer join elimination when filter's `isNotNull` constraints is unable to filter out all null-supplying rows. For example, `isnotnull(coalesce(b#227, c#238))`.

Users can hit this error when they try to use `using/natural outer join`, which is converted to a normal outer join with a `coalesce` expression on the `using columns`. For example,
```Scala
    val a = Seq((1, 2), (2, 3)).toDF("a", "b")
    val b = Seq((2, 5), (3, 4)).toDF("a", "c")
    val c = Seq((3, 1)).toDF("a", "d")
    val ab = a.join(b, Seq("a"), "fullouter")
    ab.join(c, "a").explain(true)
```
The dataframe `ab` is doing `using full-outer join`, which is converted to a normal outer join with a `coalesce` expression. Constraints inference generates a `Filter` with constraints `isnotnull(coalesce(b#227, c#238))`. Then, it triggers a wrong outer join elimination and generates a wrong result.
```
Project [a#251, b#227, c#237, d#247]
+- Join Inner, (a#251 = a#246)
   :- Project [coalesce(a#226, a#236) AS a#251, b#227, c#237]
   :  +- Join FullOuter, (a#226 = a#236)
   :     :- Project [_1#223 AS a#226, _2#224 AS b#227]
   :     :  +- LocalRelation [_1#223, _2#224]
   :     +- Project [_1#233 AS a#236, _2#234 AS c#237]
   :        +- LocalRelation [_1#233, _2#234]
   +- Project [_1#243 AS a#246, _2#244 AS d#247]
      +- LocalRelation [_1#243, _2#244]

== Optimized Logical Plan ==
Project [a#251, b#227, c#237, d#247]
+- Join Inner, (a#251 = a#246)
   :- Project [coalesce(a#226, a#236) AS a#251, b#227, c#237]
   :  +- Filter isnotnull(coalesce(a#226, a#236))
   :     +- Join FullOuter, (a#226 = a#236)
   :        :- LocalRelation [a#226, b#227]
   :        +- LocalRelation [a#236, c#237]
   +- LocalRelation [a#246, d#247]
```

**A note to the `Committer`**, please also give the credit to dongjoon-hyun who submitted another PR for fixing this issue. https://github.com/apache/spark/pull/14580

### How was this patch tested?
Added test cases

Author: gatorsmile <gatorsmile@gmail.com>

Closes #14661 from gatorsmile/fixOuterJoinElimination.
2016-08-25 14:18:58 +02:00
Takeshi YAMAMURO 2b0cc4e0df [SPARK-12978][SQL] Skip unnecessary final group-by when input data already clustered with group-by keys
This ticket targets the optimization to skip an unnecessary group-by operation below;

Without opt.:
```
== Physical Plan ==
TungstenAggregate(key=[col0#159], functions=[(sum(col1#160),mode=Final,isDistinct=false),(avg(col2#161),mode=Final,isDistinct=false)], output=[col0#159,sum(col1)#177,avg(col2)#178])
+- TungstenAggregate(key=[col0#159], functions=[(sum(col1#160),mode=Partial,isDistinct=false),(avg(col2#161),mode=Partial,isDistinct=false)], output=[col0#159,sum#200,sum#201,count#202L])
   +- TungstenExchange hashpartitioning(col0#159,200), None
      +- InMemoryColumnarTableScan [col0#159,col1#160,col2#161], InMemoryRelation [col0#159,col1#160,col2#161], true, 10000, StorageLevel(true, true, false, true, 1), ConvertToUnsafe, None
```

With opt.:
```
== Physical Plan ==
TungstenAggregate(key=[col0#159], functions=[(sum(col1#160),mode=Complete,isDistinct=false),(avg(col2#161),mode=Final,isDistinct=false)], output=[col0#159,sum(col1)#177,avg(col2)#178])
+- TungstenExchange hashpartitioning(col0#159,200), None
  +- InMemoryColumnarTableScan [col0#159,col1#160,col2#161], InMemoryRelation [col0#159,col1#160,col2#161], true, 10000, StorageLevel(true, true, false, true, 1), ConvertToUnsafe, None
```

Author: Takeshi YAMAMURO <linguin.m.s@gmail.com>

Closes #10896 from maropu/SkipGroupbySpike.
2016-08-25 12:39:58 +02:00
Liwei Lin e0b20f9f24 [SPARK-17061][SPARK-17093][SQL] MapObjects` should make copies of unsafe-backed data
## What changes were proposed in this pull request?

Currently `MapObjects` does not make copies of unsafe-backed data, leading to problems like [SPARK-17061](https://issues.apache.org/jira/browse/SPARK-17061) [SPARK-17093](https://issues.apache.org/jira/browse/SPARK-17093).

This patch makes `MapObjects` make copies of unsafe-backed data.

Generated code - prior to this patch:
```java
...
/* 295 */ if (isNull12) {
/* 296 */   convertedArray1[loopIndex1] = null;
/* 297 */ } else {
/* 298 */   convertedArray1[loopIndex1] = value12;
/* 299 */ }
...
```

Generated code - after this patch:
```java
...
/* 295 */ if (isNull12) {
/* 296 */   convertedArray1[loopIndex1] = null;
/* 297 */ } else {
/* 298 */   convertedArray1[loopIndex1] = value12 instanceof UnsafeRow? value12.copy() : value12;
/* 299 */ }
...
```

## How was this patch tested?

Add a new test case which would fail without this patch.

Author: Liwei Lin <lwlin7@gmail.com>

Closes #14698 from lw-lin/mapobjects-copy.
2016-08-25 11:24:40 +02:00
jiangxingbo 5f02d2e5b4 [SPARK-17215][SQL] Method SQLContext.parseDataType(dataTypeString: String) could be removed.
## What changes were proposed in this pull request?

Method `SQLContext.parseDataType(dataTypeString: String)` could be removed, we should use `SparkSession.parseDataType(dataTypeString: String)` instead.
This require updating PySpark.

## How was this patch tested?

Existing test cases.

Author: jiangxingbo <jiangxb1987@gmail.com>

Closes #14790 from jiangxb1987/parseDataType.
2016-08-24 23:36:04 -07:00
gatorsmile 4d0706d616 [SPARK-17190][SQL] Removal of HiveSharedState
### What changes were proposed in this pull request?
Since `HiveClient` is used to interact with the Hive metastore, it should be hidden in `HiveExternalCatalog`. After moving `HiveClient` into `HiveExternalCatalog`, `HiveSharedState` becomes a wrapper of `HiveExternalCatalog`. Thus, removal of `HiveSharedState` becomes straightforward. After removal of `HiveSharedState`, the reflection logic is directly applied on the choice of `ExternalCatalog` types, based on the configuration of `CATALOG_IMPLEMENTATION`.

~~`HiveClient` is also used/invoked by the other entities besides HiveExternalCatalog, we defines the following two APIs: getClient and getNewClient~~

### How was this patch tested?
The existing test cases

Author: gatorsmile <gatorsmile@gmail.com>

Closes #14757 from gatorsmile/removeHiveClient.
2016-08-25 12:50:03 +08:00
Sameer Agarwal ac27557eb6 [SPARK-17228][SQL] Not infer/propagate non-deterministic constraints
## What changes were proposed in this pull request?

Given that filters based on non-deterministic constraints shouldn't be pushed down in the query plan, unnecessarily inferring them is confusing and a source of potential bugs. This patch simplifies the inferring logic by simply ignoring them.

## How was this patch tested?

Added a new test in `ConstraintPropagationSuite`.

Author: Sameer Agarwal <sameerag@cs.berkeley.edu>

Closes #14795 from sameeragarwal/deterministic-constraints.
2016-08-24 21:24:24 -07:00
hyukjinkwon 29952ed096 [SPARK-16216][SQL] Read/write timestamps and dates in ISO 8601 and dateFormat/timestampFormat option for CSV and JSON
## What changes were proposed in this pull request?

### Default - ISO 8601

Currently, CSV datasource is writing `Timestamp` and `Date` as numeric form and JSON datasource is writing both as below:

- CSV
  ```
  // TimestampType
  1414459800000000
  // DateType
  16673
  ```

- Json

  ```
  // TimestampType
  1970-01-01 11:46:40.0
  // DateType
  1970-01-01
  ```

So, for CSV we can't read back what we write and for JSON it becomes ambiguous because the timezone is being missed.

So, this PR make both **write** `Timestamp` and `Date` in ISO 8601 formatted string (please refer the [ISO 8601 specification](https://www.w3.org/TR/NOTE-datetime)).

- For `Timestamp` it becomes as below: (`yyyy-MM-dd'T'HH:mm:ss.SSSZZ`)

  ```
  1970-01-01T02:00:01.000-01:00
  ```

- For `Date` it becomes as below (`yyyy-MM-dd`)

  ```
  1970-01-01
  ```

### Custom date format option - `dateFormat`

This PR also adds the support to write and read dates and timestamps in a formatted string as below:

- **DateType**

  - With `dateFormat` option (e.g. `yyyy/MM/dd`)

    ```
    +----------+
    |      date|
    +----------+
    |2015/08/26|
    |2014/10/27|
    |2016/01/28|
    +----------+
    ```

### Custom date format option - `timestampFormat`

- **TimestampType**

  - With `dateFormat` option (e.g. `dd/MM/yyyy HH:mm`)

    ```
    +----------------+
    |            date|
    +----------------+
    |2015/08/26 18:00|
    |2014/10/27 18:30|
    |2016/01/28 20:00|
    +----------------+
    ```

## How was this patch tested?

Unit tests were added in `CSVSuite` and `JsonSuite`. For JSON, existing tests cover the default cases.

Author: hyukjinkwon <gurwls223@gmail.com>

Closes #14279 from HyukjinKwon/SPARK-16216-json-csv.
2016-08-24 22:16:20 +02:00
Dongjoon Hyun 40b30fcf45 [SPARK-16983][SQL] Add prettyName for row_number, dense_rank, percent_rank, cume_dist
## What changes were proposed in this pull request?

Currently, two-word window functions like `row_number`, `dense_rank`, `percent_rank`, and `cume_dist` are expressed without `_` in error messages. We had better show the correct names.

**Before**
```scala
scala> sql("select row_number()").show
java.lang.UnsupportedOperationException: Cannot evaluate expression: rownumber()
```

**After**
```scala
scala> sql("select row_number()").show
java.lang.UnsupportedOperationException: Cannot evaluate expression: row_number()
```

## How was this patch tested?

Pass the Jenkins and manual.

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #14571 from dongjoon-hyun/SPARK-16983.
2016-08-24 21:14:40 +02:00
Wenchen Fan 52fa45d62a [SPARK-17186][SQL] remove catalog table type INDEX
## What changes were proposed in this pull request?

Actually Spark SQL doesn't support index, the catalog table type `INDEX` is from Hive. However, most operations in Spark SQL can't handle index table, e.g. create table, alter table, etc.

Logically index table should be invisible to end users, and Hive also generates special table name for index table to avoid users accessing it directly. Hive has special SQL syntax to create/show/drop index tables.

At Spark SQL side, although we can describe index table directly, but the result is unreadable, we should use the dedicated SQL syntax to do it(e.g. `SHOW INDEX ON tbl`). Spark SQL can also read index table directly, but the result is always empty.(Can hive read index table directly?)

This PR remove the table type `INDEX`, to make it clear that Spark SQL doesn't support index currently.

## How was this patch tested?

existing tests.

Author: Wenchen Fan <wenchen@databricks.com>

Closes #14752 from cloud-fan/minor2.
2016-08-23 23:46:09 -07:00
Weiqing Yang b9994ad056 [MINOR][SQL] Remove implemented functions from comments of 'HiveSessionCatalog.scala'
## What changes were proposed in this pull request?
This PR removes implemented functions from comments of `HiveSessionCatalog.scala`: `java_method`, `posexplode`, `str_to_map`.

## How was this patch tested?
Manual.

Author: Weiqing Yang <yangweiqing001@gmail.com>

Closes #14769 from Sherry302/cleanComment.
2016-08-23 23:44:45 -07:00
Josh Rosen bf8ff833e3 [SPARK-17194] Use single quotes when generating SQL for string literals
When Spark emits SQL for a string literal, it should wrap the string in single quotes, not double quotes. Databases which adhere more strictly to the ANSI SQL standards, such as Postgres, allow only single-quotes to be used for denoting string literals (see http://stackoverflow.com/a/1992331/590203).

Author: Josh Rosen <joshrosen@databricks.com>

Closes #14763 from JoshRosen/SPARK-17194.
2016-08-23 22:31:58 +02:00
Davies Liu 9afdfc94f4 [SPARK-13286] [SQL] add the next expression of SQLException as cause
## What changes were proposed in this pull request?

Some JDBC driver (for example PostgreSQL) does not use the underlying exception as cause, but have another APIs (getNextException) to access that, so it it's included in the error logging, making us hard to find the root cause, especially in batch mode.

This PR will pull out the next exception and add it as cause (if it's different) or suppressed (if there is another different cause).

## How was this patch tested?

Can't reproduce this on the default JDBC driver, so did not add a regression test.

Author: Davies Liu <davies@databricks.com>

Closes #14722 from davies/keep_cause.
2016-08-23 09:45:13 -07:00
Jacek Laskowski 9d376ad76c [SPARK-17199] Use CatalystConf.resolver for case-sensitivity comparison
## What changes were proposed in this pull request?

Use `CatalystConf.resolver` consistently for case-sensitivity comparison (removed dups).

## How was this patch tested?

Local build. Waiting for Jenkins to ensure clean build and test.

Author: Jacek Laskowski <jacek@japila.pl>

Closes #14771 from jaceklaskowski/17199-catalystconf-resolver.
2016-08-23 12:59:25 +02:00
Sean Zhong cc33460a51 [SPARK-17188][SQL] Moves class QuantileSummaries to project catalyst for implementing percentile_approx
## What changes were proposed in this pull request?

This is a sub-task of [SPARK-16283](https://issues.apache.org/jira/browse/SPARK-16283) (Implement percentile_approx SQL function), which moves class QuantileSummaries to project catalyst so that it can be reused when implementing aggregation function `percentile_approx`.

## How was this patch tested?

This PR only does class relocation, class implementation is not changed.

Author: Sean Zhong <seanzhong@databricks.com>

Closes #14754 from clockfly/move_QuantileSummaries_to_catalyst.
2016-08-23 14:57:00 +08:00
Cheng Lian 2cdd92a7cd [SPARK-17182][SQL] Mark Collect as non-deterministic
## What changes were proposed in this pull request?

This PR marks the abstract class `Collect` as non-deterministic since the results of `CollectList` and `CollectSet` depend on the actual order of input rows.

## How was this patch tested?

Existing test cases should be enough.

Author: Cheng Lian <lian@databricks.com>

Closes #14749 from liancheng/spark-17182-non-deterministic-collect.
2016-08-23 09:11:47 +08:00
gatorsmile 6d93f9e023 [SPARK-17144][SQL] Removal of useless CreateHiveTableAsSelectLogicalPlan
## What changes were proposed in this pull request?
`CreateHiveTableAsSelectLogicalPlan` is a dead code after refactoring.

## How was this patch tested?
N/A

Author: gatorsmile <gatorsmile@gmail.com>

Closes #14707 from gatorsmile/removeCreateHiveTable.
2016-08-23 08:03:08 +08:00
Eric Liang 84770b59f7 [SPARK-17162] Range does not support SQL generation
## What changes were proposed in this pull request?

The range operator previously didn't support SQL generation, which made it not possible to use in views.

## How was this patch tested?

Unit tests.

cc hvanhovell

Author: Eric Liang <ekl@databricks.com>

Closes #14724 from ericl/spark-17162.
2016-08-22 15:48:35 -07:00
Sean Zhong 929cb8beed [MINOR][SQL] Fix some typos in comments and test hints
## What changes were proposed in this pull request?

Fix some typos in comments and test hints

## How was this patch tested?

N/A.

Author: Sean Zhong <seanzhong@databricks.com>

Closes #14755 from clockfly/fix_minor_typo.
2016-08-22 13:31:38 -07:00
Davies Liu 8d35a6f68d [SPARK-17115][SQL] decrease the threshold when split expressions
## What changes were proposed in this pull request?

In 2.0, we change the threshold of splitting expressions from 16K to 64K, which cause very bad performance on wide table, because the generated method can't be JIT compiled by default (above the limit of 8K bytecode).

This PR will decrease it to 1K, based on the benchmark results for a wide table with 400 columns of LongType.

It also fix a bug around splitting expression in whole-stage codegen (it should not split them).

## How was this patch tested?

Added benchmark suite.

Author: Davies Liu <davies@databricks.com>

Closes #14692 from davies/split_exprs.
2016-08-22 16:16:03 +08:00
Wenchen Fan b2074b664a [SPARK-16498][SQL] move hive hack for data source table into HiveExternalCatalog
## What changes were proposed in this pull request?

Spark SQL doesn't have its own meta store yet, and use hive's currently. However, hive's meta store has some limitations(e.g. columns can't be too many, not case-preserving, bad decimal type support, etc.), so we have some hacks to successfully store data source table metadata into hive meta store, i.e. put all the information in table properties.

This PR moves these hacks to `HiveExternalCatalog`, tries to isolate hive specific logic in one place.

changes overview:

1.  **before this PR**: we need to put metadata(schema, partition columns, etc.) of data source tables to table properties before saving it to external catalog, even the external catalog doesn't use hive metastore(e.g. `InMemoryCatalog`)
**after this PR**: the table properties tricks are only in `HiveExternalCatalog`, the caller side doesn't need to take care of it anymore.

2. **before this PR**: because the table properties tricks are done outside of external catalog, so we also need to revert these tricks when we read the table metadata from external catalog and use it. e.g. in `DescribeTableCommand` we will read schema and partition columns from table properties.
**after this PR**: The table metadata read from external catalog is exactly the same with what we saved to it.

bonus: now we can create data source table using `SessionCatalog`, if schema is specified.
breaks: `schemaStringLengthThreshold` is not configurable anymore. `hive.default.rcfile.serde` is not configurable anymore.

## How was this patch tested?

existing tests.

Author: Wenchen Fan <wenchen@databricks.com>

Closes #14155 from cloud-fan/catalog-table.
2016-08-21 22:23:14 -07:00
Dongjoon Hyun 91c2397684 [SPARK-17098][SQL] Fix NullPropagation optimizer to handle COUNT(NULL) OVER correctly
## What changes were proposed in this pull request?

Currently, `NullPropagation` optimizer replaces `COUNT` on null literals in a bottom-up fashion. During that, `WindowExpression` is not covered properly. This PR adds the missing propagation logic.

**Before**
```scala
scala> sql("SELECT COUNT(1 + NULL) OVER ()").show
java.lang.UnsupportedOperationException: Cannot evaluate expression: cast(0 as bigint) windowspecdefinition(ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING)
```

**After**
```scala
scala> sql("SELECT COUNT(1 + NULL) OVER ()").show
+----------------------------------------------------------------------------------------------+
|count((1 + CAST(NULL AS INT))) OVER (ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING)|
+----------------------------------------------------------------------------------------------+
|                                                                                             0|
+----------------------------------------------------------------------------------------------+
```

## How was this patch tested?

Pass the Jenkins test with a new test case.

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #14689 from dongjoon-hyun/SPARK-17098.
2016-08-21 22:07:47 +02:00
petermaxlee 9560c8d295 [SPARK-17124][SQL] RelationalGroupedDataset.agg should preserve order and allow multiple aggregates per column
## What changes were proposed in this pull request?
This patch fixes a longstanding issue with one of the RelationalGroupedDataset.agg function. Even though the signature accepts vararg of pairs, the underlying implementation turns the seq into a map, and thus not order preserving nor allowing multiple aggregates per column.

This change also allows users to use this function to run multiple different aggregations for a single column, e.g.
```
agg("age" -> "max", "age" -> "count")
```

## How was this patch tested?
Added a test case in DataFrameAggregateSuite.

Author: petermaxlee <petermaxlee@gmail.com>

Closes #14697 from petermaxlee/SPARK-17124.
2016-08-21 00:25:55 +08:00
Liang-Chi Hsieh 31a0155720 [SPARK-17104][SQL] LogicalRelation.newInstance should follow the semantics of MultiInstanceRelation
## What changes were proposed in this pull request?

Currently `LogicalRelation.newInstance()` simply creates another `LogicalRelation` object with the same parameters. However, the `newInstance()` method inherited from `MultiInstanceRelation` should return a copy of object with unique expression ids. Current `LogicalRelation.newInstance()` can cause failure when doing self-join.

## How was this patch tested?

Jenkins tests.

Author: Liang-Chi Hsieh <simonh@tw.ibm.com>

Closes #14682 from viirya/fix-localrelation.
2016-08-20 23:29:48 +08:00
petermaxlee 45d40d9f66 [SPARK-17150][SQL] Support SQL generation for inline tables
## What changes were proposed in this pull request?
This patch adds support for SQL generation for inline tables. With this, it would be possible to create a view that depends on inline tables.

## How was this patch tested?
Added a test case in LogicalPlanToSQLSuite.

Author: petermaxlee <petermaxlee@gmail.com>

Closes #14709 from petermaxlee/SPARK-17150.
2016-08-20 13:19:38 +08:00
Srinath Shankar ba1737c21a [SPARK-17158][SQL] Change error message for out of range numeric literals
## What changes were proposed in this pull request?

Modifies error message for numeric literals to
Numeric literal <literal> does not fit in range [min, max] for type <T>

## How was this patch tested?

Fixed up the error messages for literals.sql in  SqlQueryTestSuite and re-ran via sbt. Also fixed up error messages in ExpressionParserSuite

Author: Srinath Shankar <srinath@databricks.com>

Closes #14721 from srinathshankar/sc4296.
2016-08-19 19:54:26 -07:00
petermaxlee a117afa7c2 [SPARK-17149][SQL] array.sql for testing array related functions
## What changes were proposed in this pull request?
This patch creates array.sql in SQLQueryTestSuite for testing array related functions, including:

- indexing
- array creation
- size
- array_contains
- sort_array

## How was this patch tested?
The patch itself is about adding tests.

Author: petermaxlee <petermaxlee@gmail.com>

Closes #14708 from petermaxlee/SPARK-17149.
2016-08-19 18:14:45 -07:00
Reynold Xin 67e59d464f [SPARK-16994][SQL] Whitelist operators for predicate pushdown
## What changes were proposed in this pull request?
This patch changes predicate pushdown optimization rule (PushDownPredicate) from using a blacklist to a whitelist. That is to say, operators must be explicitly allowed. This approach is more future-proof: previously it was possible for us to introduce a new operator and then render the optimization rule incorrect.

This also fixes the bug that previously we allowed pushing filter beneath limit, which was incorrect. That is to say, before this patch, the optimizer would rewrite
```
select * from (select * from range(10) limit 5) where id > 3

to

select * from range(10) where id > 3 limit 5
```

## How was this patch tested?
- a unit test case in FilterPushdownSuite
- an end-to-end test in limit.sql

Author: Reynold Xin <rxin@databricks.com>

Closes #14713 from rxin/SPARK-16994.
2016-08-19 21:11:35 +08:00
Reynold Xin b482c09fa2 HOTFIX: compilation broken due to protected ctor. 2016-08-18 19:02:32 -07:00
petermaxlee f5472dda51 [SPARK-16947][SQL] Support type coercion and foldable expression for inline tables
## What changes were proposed in this pull request?
This patch improves inline table support with the following:

1. Support type coercion.
2. Support using foldable expressions. Previously only literals were supported.
3. Improve error message handling.
4. Improve test coverage.

## How was this patch tested?
Added a new unit test suite ResolveInlineTablesSuite and a new file-based end-to-end test inline-table.sql.

Author: petermaxlee <petermaxlee@gmail.com>

Closes #14676 from petermaxlee/SPARK-16947.
2016-08-19 09:19:47 +08:00
petermaxlee 68f5087d21 [SPARK-17117][SQL] 1 / NULL should not fail analysis
## What changes were proposed in this pull request?
This patch fixes the problem described in SPARK-17117, i.e. "SELECT 1 / NULL" throws an analysis exception:

```
org.apache.spark.sql.AnalysisException: cannot resolve '(1 / NULL)' due to data type mismatch: differing types in '(1 / NULL)' (int and null).
```

The problem is that division type coercion did not take null type into account.

## How was this patch tested?
A unit test for the type coercion, and a few end-to-end test cases using SQLQueryTestSuite.

Author: petermaxlee <petermaxlee@gmail.com>

Closes #14695 from petermaxlee/SPARK-17117.
2016-08-18 13:44:13 +02:00
Eric Liang 412dba63b5 [SPARK-17069] Expose spark.range() as table-valued function in SQL
## What changes were proposed in this pull request?

This adds analyzer rules for resolving table-valued functions, and adds one builtin implementation for range(). The arguments for range() are the same as those of `spark.range()`.

## How was this patch tested?

Unit tests.

cc hvanhovell

Author: Eric Liang <ekl@databricks.com>

Closes #14656 from ericl/sc-4309.
2016-08-18 13:33:55 +02:00
Liang-Chi Hsieh e82dbe600e [SPARK-17107][SQL] Remove redundant pushdown rule for Union
## What changes were proposed in this pull request?

The `Optimizer` rules `PushThroughSetOperations` and `PushDownPredicate` have a redundant rule to push down `Filter` through `Union`. We should remove it.

## How was this patch tested?

Jenkins tests.

Author: Liang-Chi Hsieh <simonh@tw.ibm.com>

Closes #14687 from viirya/remove-extra-pushdown.
2016-08-18 12:45:56 +02:00
Reynold Xin 1748f82410 [SPARK-16391][SQL] Support partial aggregation for reduceGroups
## What changes were proposed in this pull request?
This patch introduces a new private ReduceAggregator interface that is a subclass of Aggregator. ReduceAggregator only requires a single associative and commutative reduce function. ReduceAggregator is also used to implement KeyValueGroupedDataset.reduceGroups in order to support partial aggregation.

Note that the pull request was initially done by viirya.

## How was this patch tested?
Covered by original tests for reduceGroups, as well as a new test suite for ReduceAggregator.

Author: Reynold Xin <rxin@databricks.com>
Author: Liang-Chi Hsieh <simonh@tw.ibm.com>

Closes #14576 from rxin/reduceAggregator.
2016-08-18 16:37:25 +08:00
petermaxlee 3e6ef2e8a4 [SPARK-17034][SQL] Minor code cleanup for UnresolvedOrdinal
## What changes were proposed in this pull request?
I was looking at the code for UnresolvedOrdinal and made a few small changes to make it slightly more clear:

1. Rename the rule to SubstituteUnresolvedOrdinals which is more consistent with other rules that start with verbs. Note that this is still inconsistent with CTESubstitution and WindowsSubstitution.
2. Broke the test suite down from a single test case to three test cases.

## How was this patch tested?
This is a minor cleanup.

Author: petermaxlee <petermaxlee@gmail.com>

Closes #14672 from petermaxlee/SPARK-17034.
2016-08-18 16:17:01 +08:00
Liang-Chi Hsieh 10204b9d29 [SPARK-16995][SQL] TreeNodeException when flat mapping RelationalGroupedDataset created from DataFrame containing a column created with lit/expr
## What changes were proposed in this pull request?

A TreeNodeException is thrown when executing the following minimal example in Spark 2.0.

    import spark.implicits._
    case class test (x: Int, q: Int)

    val d = Seq(1).toDF("x")
    d.withColumn("q", lit(0)).as[test].groupByKey(_.x).flatMapGroups{case (x, iter) => List[Int]()}.show
    d.withColumn("q", expr("0")).as[test].groupByKey(_.x).flatMapGroups{case (x, iter) => List[Int]()}.show

The problem is at `FoldablePropagation`. The rule will do `transformExpressions` on `LogicalPlan`. The query above contains a `MapGroups` which has a parameter `dataAttributes:Seq[Attribute]`. One attributes in `dataAttributes` will be transformed to an `Alias(literal(0), _)` in `FoldablePropagation`. `Alias` is not an `Attribute` and causes the error.

We can't easily detect such type inconsistency during transforming expressions. A direct approach to this problem is to skip doing `FoldablePropagation` on object operators as they should not contain such expressions.

## How was this patch tested?

Jenkins tests.

Author: Liang-Chi Hsieh <simonh@tw.ibm.com>

Closes #14648 from viirya/flat-mapping.
2016-08-18 13:24:12 +08:00
Tathagata Das d60af8f6aa [SPARK-17096][SQL][STREAMING] Improve exception string reported through the StreamingQueryListener
## What changes were proposed in this pull request?

Currently, the stackTrace (as `Array[StackTraceElements]`) reported through StreamingQueryListener.onQueryTerminated is useless as it has the stack trace of where StreamingQueryException is defined, not the stack trace of underlying exception.  For example, if a streaming query fails because of a / by zero exception in a task, the `QueryTerminated.stackTrace` will have
```
org.apache.spark.sql.execution.streaming.StreamExecution.org$apache$spark$sql$execution$streaming$StreamExecution$$runBatches(StreamExecution.scala:211)
org.apache.spark.sql.execution.streaming.StreamExecution$$anon$1.run(StreamExecution.scala:124)
```
This is basically useless, as it is location where the StreamingQueryException was defined. What we want is

Here is the right way to reason about what should be posted as through StreamingQueryListener.onQueryTerminated
- The actual exception could either be a SparkException, or an arbitrary exception.
  - SparkException reports the relevant executor stack trace of a failed task as a string in the the exception message. The `Array[StackTraceElements]` returned by `SparkException.stackTrace()` is mostly irrelevant.
  - For any arbitrary exception, the `Array[StackTraceElements]` returned by `exception.stackTrace()` may be relevant.
- When there is an error in a streaming query, it's hard to reason whether the `Array[StackTraceElements]` is useful or not. In fact, it is not clear whether it is even useful to report the stack trace as this array of Java objects. It may be sufficient to report the strack trace as a string, along with the message. This is how Spark reported executor stra
- Hence, this PR simplifies the API by removing the array `stackTrace` from `QueryTerminated`. Instead the `exception` returns a string containing the message and the stack trace of the actual underlying exception that failed the streaming query (i.e. not that of the StreamingQueryException). If anyone is interested in the actual stack trace as an array, can always access them through `streamingQuery.exception` which returns the exception object.

With this change, if a streaming query fails because of a / by zero exception in a task, the `QueryTerminated.exception` will be
```
org.apache.spark.SparkException: Job aborted due to stage failure: Task 1 in stage 0.0 failed 1 times, most recent failure: Lost task 1.0 in stage 0.0 (TID 1, localhost): java.lang.ArithmeticException: / by zero
	at org.apache.spark.sql.streaming.StreamingQueryListenerSuite$$anonfun$5$$anonfun$apply$mcV$sp$4$$anonfun$apply$mcV$sp$5.apply$mcII$sp(StreamingQueryListenerSuite.scala:153)
	at org.apache.spark.sql.streaming.StreamingQueryListenerSuite$$anonfun$5$$anonfun$apply$mcV$sp$4$$anonfun$apply$mcV$sp$5.apply(StreamingQueryListenerSuite.scala:153)
	at org.apache.spark.sql.streaming.StreamingQueryListenerSuite$$anonfun$5$$anonfun$apply$mcV$sp$4$$anonfun$apply$mcV$sp$5.apply(StreamingQueryListenerSuite.scala:153)
	at org.apache.spark.sql.catalyst.expressions.GeneratedClass$GeneratedIterator.processNext(Unknown Source)
	at org.apache.spark.sql.execution.BufferedRowIterator.hasNext(BufferedRowIterator.java:43)
	at org.apache.spark.sql.execution.WholeStageCodegenExec$$anonfun$8$$anon$1.hasNext(WholeStageCodegenExec.scala:370)
	at org.apache.spark.sql.execution.SparkPlan$$anonfun$2.apply(SparkPlan.scala:232)
	at org.apache.spark.sql.execution.SparkPlan$$anonfun$2.apply(SparkPlan.scala:226)
	at org.apache.spark.rdd.RDD$$anonfun$mapPartitionsInternal$1$$anonfun$apply$24.apply(RDD.scala:803)
	at org.apache.spark.rdd.RDD$$anonfun$mapPartitionsInternal$1$$anonfun$apply$24.apply(RDD.scala:803)
	at org.apache.spark.rdd.MapPartitionsRDD.compute(MapPartitionsRDD.scala:38)
	at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:319)
	at org.apache.spark.rdd.RDD.iterator(RDD.scala:283)
	at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:70)
	at org.apache.spark.scheduler.Task.run(Task.scala:86)
	at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:274)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:744)

Driver stacktrace:
	at org.apache.spark.scheduler.DAGScheduler.org$apache$spark$scheduler$DAGScheduler$$failJobAndIndependentStages(DAGScheduler.scala:1429)
	at org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:1417)
	at org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:1416)
	at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:59)
	at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:48)
	at org.apache.spark.scheduler.DAGScheduler.abortStage(DAGScheduler.scala:1416)
	at org.apache.spark.scheduler.DAGScheduler$$anonfun$handleTaskSetFailed$1.apply(DAGScheduler.scala:802)
	at org.apache.spark.scheduler.DAGScheduler$$anonfun$handleTaskSetFailed$1.apply(DAGScheduler.scala:802)
...
```
It contains the relevant executor stack trace. In a case non-SparkException, if the streaming source MemoryStream throws an exception, exception message will have the relevant stack trace.
```
java.lang.RuntimeException: this is the exception message
	at org.apache.spark.sql.execution.streaming.MemoryStream.getBatch(memory.scala:103)
	at org.apache.spark.sql.execution.streaming.StreamExecution$$anonfun$5.apply(StreamExecution.scala:316)
	at org.apache.spark.sql.execution.streaming.StreamExecution$$anonfun$5.apply(StreamExecution.scala:313)
	at scala.collection.TraversableLike$$anonfun$flatMap$1.apply(TraversableLike.scala:241)
	at scala.collection.TraversableLike$$anonfun$flatMap$1.apply(TraversableLike.scala:241)
	at scala.collection.Iterator$class.foreach(Iterator.scala:893)
	at scala.collection.AbstractIterator.foreach(Iterator.scala:1336)
	at scala.collection.IterableLike$class.foreach(IterableLike.scala:72)
	at org.apache.spark.sql.execution.streaming.StreamProgress.foreach(StreamProgress.scala:25)
	at scala.collection.TraversableLike$class.flatMap(TraversableLike.scala:241)
	at org.apache.spark.sql.execution.streaming.StreamProgress.flatMap(StreamProgress.scala:25)
	at org.apache.spark.sql.execution.streaming.StreamExecution.org$apache$spark$sql$execution$streaming$StreamExecution$$runBatch(StreamExecution.scala:313)
	at org.apache.spark.sql.execution.streaming.StreamExecution$$anonfun$org$apache$spark$sql$execution$streaming$StreamExecution$$runBatches$1.apply$mcZ$sp(StreamExecution.scala:197)
	at org.apache.spark.sql.execution.streaming.ProcessingTimeExecutor.execute(TriggerExecutor.scala:43)
	at org.apache.spark.sql.execution.streaming.StreamExecution.org$apache$spark$sql$execution$streaming$StreamExecution$$runBatches(StreamExecution.scala:187)
	at org.apache.spark.sql.execution.streaming.StreamExecution$$anon$1.run(StreamExecution.scala:124)
```

Note that this change in the public `QueryTerminated` class is okay as the APIs are still experimental.

## How was this patch tested?
Unit tests that test whether the right information is present in the exception message reported through QueryTerminated object.

Author: Tathagata Das <tathagata.das1565@gmail.com>

Closes #14675 from tdas/SPARK-17096.
2016-08-17 13:31:34 -07:00
Steve Loughran cc97ea188e [SPARK-16736][CORE][SQL] purge superfluous fs calls
A review of the code, working back from Hadoop's `FileSystem.exists()` and `FileSystem.isDirectory()` code, then removing uses of the calls when superfluous.

1. delete is harmless if called on a nonexistent path, so don't do any checks before deletes
1. any `FileSystem.exists()`  check before `getFileStatus()` or `open()` is superfluous as the operation itself does the check. Instead the `FileNotFoundException` is caught and triggers the downgraded path. When a `FileNotFoundException` was thrown before, the code still creates a new FNFE with the error messages. Though now the inner exceptions are nested, for easier diagnostics.

Initially, relying on Jenkins test runs.

One troublespot here is that some of the codepaths are clearly error situations; it's not clear that they have coverage anyway. Trying to create the failure conditions in tests would be ideal, but it will also be hard.

Author: Steve Loughran <stevel@apache.org>

Closes #14371 from steveloughran/cloud/SPARK-16736-superfluous-fs-calls.
2016-08-17 11:43:01 -07:00
Wenchen Fan 928ca1c6d1 [SPARK-17102][SQL] bypass UserDefinedGenerator for json format check
## What changes were proposed in this pull request?

We use reflection to convert `TreeNode` to json string, and currently don't support arbitrary object. `UserDefinedGenerator` takes a function object, so we should skip json format test for it, or the tests can be flacky, e.g. `DataFrameSuite.simple explode`, this test always fail with scala 2.10(branch 1.6 builds with scala 2.10 by default), but pass with scala 2.11(master branch builds with scala 2.11 by default).

## How was this patch tested?

N/A

Author: Wenchen Fan <wenchen@databricks.com>

Closes #14679 from cloud-fan/json.
2016-08-17 09:31:22 -07:00
Herman van Hovell 0b0c8b95e3 [SPARK-17106] [SQL] Simplify the SubqueryExpression interface
## What changes were proposed in this pull request?
The current subquery expression interface contains a little bit of technical debt in the form of a few different access paths to get and set the query contained by the expression. This is confusing to anyone who goes over this code.

This PR unifies these access paths.

## How was this patch tested?
(Existing tests)

Author: Herman van Hovell <hvanhovell@databricks.com>

Closes #14685 from hvanhovell/SPARK-17106.
2016-08-17 07:03:24 -07:00
Kazuaki Ishizaki 56d86742d2 [SPARK-15285][SQL] Generated SpecificSafeProjection.apply method grows beyond 64 KB
## What changes were proposed in this pull request?

This PR splits the generated code for ```SafeProjection.apply``` by using ```ctx.splitExpressions()```. This is because the large code body for ```NewInstance``` may grow beyond 64KB bytecode size for ```apply()``` method.

Here is [the original PR](https://github.com/apache/spark/pull/13243) for SPARK-15285. However, it breaks a build with Scala 2.10 since Scala 2.10 does not a case class with large number of members. Thus, it was reverted by [this commit](fa244e5a90).

## How was this patch tested?

Added new tests by using `DefinedByConstructorParams` instead of case class for scala-2.10

Author: Kazuaki Ishizaki <ishizaki@jp.ibm.com>

Closes #14670 from kiszk/SPARK-15285-2.
2016-08-17 21:34:57 +08:00
jiangxingbo 4d0cc84afc [SPARK-17032][SQL] Add test cases for methods in ParserUtils.
## What changes were proposed in this pull request?

Currently methods in `ParserUtils` are tested indirectly, we should add test cases in `ParserUtilsSuite` to verify their integrity directly.

## How was this patch tested?

New test cases in `ParserUtilsSuite`

Author: jiangxingbo <jiangxb1987@gmail.com>

Closes #14620 from jiangxb1987/parserUtils.
2016-08-17 14:22:36 +02:00
Herman van Hovell f7c9ff57c1 [SPARK-17068][SQL] Make view-usage visible during analysis
## What changes were proposed in this pull request?
This PR adds a field to subquery alias in order to make the usage of views in a resolved `LogicalPlan` more visible (and more understandable).

For example, the following view and query:
```sql
create view constants as select 1 as id union all select 1 union all select 42
select * from constants;
```
...now yields the following analyzed plan:
```
Project [id#39]
+- SubqueryAlias c, `default`.`constants`
   +- Project [gen_attr_0#36 AS id#39]
      +- SubqueryAlias gen_subquery_0
         +- Union
            :- Union
            :  :- Project [1 AS gen_attr_0#36]
            :  :  +- OneRowRelation$
            :  +- Project [1 AS gen_attr_1#37]
            :     +- OneRowRelation$
            +- Project [42 AS gen_attr_2#38]
               +- OneRowRelation$
```
## How was this patch tested?
Added tests for the two code paths in `SessionCatalogSuite` (sql/core) and `HiveMetastoreCatalogSuite` (sql/hive)

Author: Herman van Hovell <hvanhovell@databricks.com>

Closes #14657 from hvanhovell/SPARK-17068.
2016-08-16 23:09:53 -07:00
Herman van Hovell 4a2c375be2 [SPARK-17084][SQL] Rename ParserUtils.assert to validate
## What changes were proposed in this pull request?
This PR renames `ParserUtils.assert` to `ParserUtils.validate`. This is done because this method is used to check requirements, and not to check if the program is in an invalid state.

## How was this patch tested?
Simple rename. Compilation should do.

Author: Herman van Hovell <hvanhovell@databricks.com>

Closes #14665 from hvanhovell/SPARK-17084.
2016-08-16 21:35:39 -07:00