## What changes were proposed in this pull request?

Currently, if we read a batch and want to display it on the console sink, it will lead a runtime exception.

Changes:

- In this PR, we add a match rule to check whether it is a ConsoleSinkProvider, we will display the Dataset
 if using console format.

## How was this patch tested?

spark.read.schema().json(path).write.format("console").save

Author: Lubo Zhang <lubo.zhang@intel.com>
Author: lubozhan <lubo.zhang@intel.com>

Closes #18347 from lubozhan/dev.

## What changes were proposed in this pull request?
Fix incomplete documentation for `lpad`.

Author: actuaryzhang <actuaryzhang10@gmail.com>

Closes #18367 from actuaryzhang/SQLDoc.

## What changes were proposed in this pull request?

Decode the path generated by File sink to handle special characters.

## How was this patch tested?

The added unit test.

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #18381 from zsxwing/SPARK-21167.

[SPARK-21147][SS] Throws an analysis exception when a user-specified schema is given in socket/rate sources

## What changes were proposed in this pull request?

This PR proposes to throw an exception if a schema is provided by user to socket source as below:

**socket source**

```scala
import org.apache.spark.sql.types._

val userSpecifiedSchema = StructType(
  StructField("name", StringType) ::
  StructField("area", StringType) :: Nil)
val df = spark.readStream.format("socket").option("host", "localhost").option("port", 9999).schema(userSpecifiedSchema).load
df.printSchema
```

Before

```
root
 |-- value: string (nullable = true)
```

After

```
org.apache.spark.sql.AnalysisException: The socket source does not support a user-specified schema.;
  at org.apache.spark.sql.execution.streaming.TextSocketSourceProvider.sourceSchema(socket.scala:199)
  at org.apache.spark.sql.execution.datasources.DataSource.sourceSchema(DataSource.scala:192)
  at org.apache.spark.sql.execution.datasources.DataSource.sourceInfo$lzycompute(DataSource.scala:87)
  at org.apache.spark.sql.execution.datasources.DataSource.sourceInfo(DataSource.scala:87)
  at org.apache.spark.sql.execution.streaming.StreamingRelation$.apply(StreamingRelation.scala:30)
  at org.apache.spark.sql.streaming.DataStreamReader.load(DataStreamReader.scala:150)
  ... 50 elided
```

**rate source**

```scala
spark.readStream.format("rate").schema(spark.range(1).schema).load().printSchema()
```

Before

```
root
 |-- timestamp: timestamp (nullable = true)
 |-- value: long (nullable = true)`
```

After

```
org.apache.spark.sql.AnalysisException: The rate source does not support a user-specified schema.;
  at org.apache.spark.sql.execution.streaming.RateSourceProvider.sourceSchema(RateSourceProvider.scala:57)
  at org.apache.spark.sql.execution.datasources.DataSource.sourceSchema(DataSource.scala:192)
  at org.apache.spark.sql.execution.datasources.DataSource.sourceInfo$lzycompute(DataSource.scala:87)
  at org.apache.spark.sql.execution.datasources.DataSource.sourceInfo(DataSource.scala:87)
  at org.apache.spark.sql.execution.streaming.StreamingRelation$.apply(StreamingRelation.scala:30)
  at org.apache.spark.sql.streaming.DataStreamReader.load(DataStreamReader.scala:150)
  ... 48 elided
```

## How was this patch tested?

Unit test in `TextSocketStreamSuite` and `RateSourceSuite`.

Author: hyukjinkwon <gurwls223@gmail.com>

Closes #18365 from HyukjinKwon/SPARK-21147.

## What changes were proposed in this pull request?

Currently we have several tens of test sqls in catalyst will fail at `SimpleAnalyzer.checkAnalysis`, we should make sure they are valid.

This PR makes the following changes:
1. Apply `checkAnalysis` on plans that tests `Optimizer` rules, but don't require the testcases for `Parser`/`Analyzer` pass `checkAnalysis`;
2. Fix testcases for `Optimizer` that would have fall.
## How was this patch tested?

Apply `SimpleAnalyzer.checkAnalysis` on plans in `PlanTest.comparePlans`, update invalid test cases.

Author: Xingbo Jiang <xingbo.jiang@databricks.com>
Author: jiangxingbo <jiangxb1987@gmail.com>

Closes #15417 from jiangxb1987/cptest.

## What changes were proposed in this pull request?

This PR aims to clarify some outdated comments that i found at **spark-catalyst** and **spark-sql** pom files. Maven bug still happening and in order to track it I have updated the issue link and also the status of the issue.

Author: Marcos P <mpenate@stratio.com>

Closes #18374 from mpenate/fix/mng-3559-comment.

This patch adds DB2 specific data type mappings for decfloat, real, xml , and timestamp with time zone (DB2Z specific type)  types on read and for byte, short data types  on write to the to jdbc data source DB2 dialect. Default mapping does not work for these types when reading/writing from DB2 database.

Added docker test, and a JDBC unit test case.

Author: sureshthalamati <suresh.thalamati@gmail.com>

Closes #9162 from sureshthalamati/db2dialect_enhancements-spark-10655.

## What changes were proposed in this pull request?
QueryPlanConstraints should be part of LogicalPlan, rather than QueryPlan, since the constraint framework is only used for query plan rewriting and not for physical planning.

## How was this patch tested?
Should be covered by existing tests, since it is a simple refactoring.

Author: Reynold Xin <rxin@databricks.com>

Closes #18310 from rxin/SPARK-21103.

## What changes were proposed in this pull request?

This is a regression in Spark 2.2. In Spark 2.2, we introduced a new way to resolve persisted view: https://issues.apache.org/jira/browse/SPARK-18209 , but this makes the persisted view non case-preserving because we store the schema in hive metastore directly. We should follow data source table and store schema in table properties.

## How was this patch tested?

new regression test

Author: Wenchen Fan <wenchen@databricks.com>

Closes #18360 from cloud-fan/view.

## What changes were proposed in this pull request?

Fix some typo of the document.

## How was this patch tested?

Existing tests.

Please review http://spark.apache.org/contributing.html before opening a pull request.

Author: Xianyang Liu <xianyang.liu@intel.com>

Closes #18350 from ConeyLiu/fixtypo.

## What changes were proposed in this pull request?

This PR cleans up a few Java linter errors for Apache Spark 2.2 release.

## How was this patch tested?

```bash
$ dev/lint-java
Using `mvn` from path: /usr/local/bin/mvn
Checkstyle checks passed.
```

We can check the result at Travis CI, [here](https://travis-ci.org/dongjoon-hyun/spark/builds/244297894).

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #18345 from dongjoon-hyun/fix_lint_java_2.

## What changes were proposed in this pull request?

This fix tries to address the issue in SPARK-19975 where we
have `map_keys` and `map_values` functions in SQL yet there
is no Python equivalent functions.

This fix adds `map_keys` and `map_values` functions to Python.

## How was this patch tested?

This fix is tested manually (See Python docs for examples).

Author: Yong Tang <yong.tang.github@outlook.com>

Closes #17328 from yongtang/SPARK-19975.

### What changes were proposed in this pull request?
We should not silently ignore `DISTINCT` when they are not supported in the function arguments. This PR is to block these cases and issue the error messages.

### How was this patch tested?
Added test cases for both regular functions and window functions

Author: Xiao Li <gatorsmile@gmail.com>

Closes #18340 from gatorsmile/firstCount.

## What changes were proposed in this pull request?

Built-in SQL Function UnaryMinus/UnaryPositive support string type, if it's string type, convert it to double type, after this PR:
```sql
spark-sql> select positive('-1.11'), negative('-1.11');
-1.11   1.11
spark-sql>
```

## How was this patch tested?

unit tests

Author: Yuming Wang <wgyumg@gmail.com>

Closes #18173 from wangyum/SPARK-20948.

## What changes were proposed in this pull request?

The function `char_length` is shorthand for `character_length` function. Both Hive and Postgresql support `character_length`,  This PR add support for `character_length`.

Ref:
https://cwiki.apache.org/confluence/display/Hive/LanguageManual+UDF#LanguageManualUDF-StringFunctions
https://www.postgresql.org/docs/current/static/functions-string.html

## How was this patch tested?

unit tests

Author: Yuming Wang <wgyumg@gmail.com>

Closes #18330 from wangyum/SPARK-20749-character_length.

## What changes were proposed in this pull request?

ABS function support string type. Hive/MySQL support this feature.

Ref: https://github.com/apache/hive/blob/4ba713ccd85c3706d195aeef9476e6e6363f1c21/ql/src/java/org/apache/hadoop/hive/ql/udf/generic/GenericUDFAbs.java#L93

## How was this patch tested?
 unit tests

Author: Yuming Wang <wgyumg@gmail.com>

Closes #18153 from wangyum/SPARK-20931.

## What changes were proposed in this pull request?

Previous code mistakenly use `table.properties.get("comment")` to read the existing table comment, we should use `table.comment`

## How was this patch tested?

new regression test

Author: Wenchen Fan <wenchen@databricks.com>

Closes #18325 from cloud-fan/unset.

## What changes were proposed in this pull request?

This PR adds built-in SQL function `BIT_LENGTH()`, `CHAR_LENGTH()`, and `OCTET_LENGTH()` functions.

`BIT_LENGTH()` returns the bit length of the given string or binary expression.
`CHAR_LENGTH()` returns the length of the given string or binary expression. (i.e. equal to `LENGTH()`)
`OCTET_LENGTH()` returns the byte length of the given string or binary expression.

## How was this patch tested?

Added new test suites for these three functions

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

Closes #18046 from kiszk/SPARK-20749.

## What changes were proposed in this pull request?

Just as the function name and comments of `TreeNode.mapChildren` mentioned, the function should be apply to all currently node children. So, the follow code should judge whether it is the children node.

https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/trees/TreeNode.scala#L342

## How was this patch tested?

Existing tests.

Author: Xianyang Liu <xianyang.liu@intel.com>

Closes #18284 from ConeyLiu/treenode.

### What changes were proposed in this pull request?
`ALTER TABLE SET TBLPROPERTIES` should not overwrite `COMMENT` even if the input property does not have the property of `COMMENT`. This PR is to fix the issue.

### How was this patch tested?
Covered by the existing tests.

Author: Xiao Li <gatorsmile@gmail.com>

Closes #18318 from gatorsmile/fixTableComment.

## What changes were proposed in this pull request?

This pull-request exclusively includes the class splitting feature described in #16648. When code for a given class would grow beyond 1600k bytes, a private, nested sub-class is generated into which subsequent functions are inlined. Additional sub-classes are generated as the code threshold is met subsequent times. This code includes 3 changes:

1. Includes helper maps, lists, and functions for keeping track of sub-classes during code generation (included in the `CodeGenerator` class). These helper functions allow nested classes and split functions to be initialized/declared/inlined to the appropriate locations in the various projection classes.
2. Changes `addNewFunction` to return a string to support instances where a split function is inlined to a nested class and not the outer class (and so must be invoked using the class-qualified name). Uses of `addNewFunction` throughout the codebase are modified so that the returned name is properly used.
3. Removes instances of the `this` keyword when used on data inside generated classes. All state declared in the outer class is by default global and accessible to the nested classes. However, if a reference to global state in a nested class is prepended with the `this` keyword, it would attempt to reference state belonging to the nested class (which would not exist), rather than the correct variable belonging to the outer class.

## How was this patch tested?

Added a test case to the `GeneratedProjectionSuite` that increases the number of columns tested in various projections to a threshold that would previously have triggered a `JaninoRuntimeException` for the Constant Pool.

Note: This PR does not address the second Constant Pool issue with code generation (also mentioned in #16648): excess global mutable state. A second PR may be opened to resolve that issue.

Author: ALeksander Eskilson <alek.eskilson@cerner.com>

Closes #18075 from bdrillard/class_splitting_only.

### What changes were proposed in this pull request?
The current option name `wholeFile` is misleading for CSV users. Currently, it is not representing a record per file. Actually, one file could have multiple records. Thus, we should rename it. Now, the proposal is `multiLine`.

### How was this patch tested?
N/A

Author: Xiao Li <gatorsmile@gmail.com>

Closes #18202 from gatorsmile/renameCVSOption.

## What changes were proposed in this pull request?
It is really painful to not have configs in logical plan and expressions. We had to add all sorts of hacks (e.g. pass SQLConf explicitly in functions). This patch exposes SQLConf in logical plan, using a thread local variable and a getter closure that's set once there is an active SparkSession.

The implementation is a bit of a hack, since we didn't anticipate this need in the beginning (config was only exposed in physical plan). The implementation is described in `SQLConf.get`.

In terms of future work, we should follow up to clean up CBO (remove the need for passing in config).

## How was this patch tested?
Updated relevant tests for constraint propagation.

Author: Reynold Xin <rxin@databricks.com>

Closes #18299 from rxin/SPARK-21092.

## What changes were proposed in this pull request?
This patch moves constraint related code into a separate trait QueryPlanConstraints, so we don't litter QueryPlan with a lot of constraint private functions.

## How was this patch tested?
This is a simple move refactoring and should be covered by existing tests.

Author: Reynold Xin <rxin@databricks.com>

Closes #18298 from rxin/SPARK-21091.

This reverts commit f7cf2096.

### What changes were proposed in this pull request?

Since both table properties and storage properties share the same key values, table properties are not shown in the output of DESC EXTENDED/FORMATTED when the storage properties are not empty.

This PR is to fix the above issue by renaming them to different keys.

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

Author: Xiao Li <gatorsmile@gmail.com>

Closes #18294 from gatorsmile/tableProperties.

### What changes were proposed in this pull request?
Before the PR, Spark is unable to read the partitioned table created by Spark 2.1 when the table schema does not put the partitioning column at the end of the schema.
[assert(partitionFields.map(_.name) == partitionColumnNames)](https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/catalog/interface.scala#L234-L236)

When reading the table metadata from the metastore, we also need to reorder the columns.

### How was this patch tested?
Added test cases to check both Hive-serde and data source tables.

Author: gatorsmile <gatorsmile@gmail.com>

Closes #18295 from gatorsmile/reorderReadSchema.

## What changes were proposed in this pull request?

https://github.com/apache/spark/pull/18106 Support TRUNC (number),  We should also add function alias for `MOD `and `POSITION`.

`POSITION(substr IN str) `is a synonym for `LOCATE(substr,str)`. same as MySQL: https://dev.mysql.com/doc/refman/5.7/en/string-functions.html#function_position

## How was this patch tested?

unit tests

Author: Yuming Wang <wgyumg@gmail.com>

Closes #18206 from wangyum/SPARK-20754-mod&position.

## What changes were proposed in this pull request?
After PruneFileSourcePartitions rule, It needs reset table's statistics because PruneFileSourcePartitions can filter some unnecessary partitions. So the statistics need to be changed.

## How was this patch tested?
add unit test.

Author: lianhuiwang <lianhuiwang09@gmail.com>

Closes #18205 from lianhuiwang/SPARK-20986.

## What changes were proposed in this pull request?
When converting `string` to `number`(int, long or double),  if the string has a space before or after,will lead to unnecessary mistakes.

## How was this patch tested?
unit test

Author: liuxian <liu.xian3@zte.com.cn>

Closes #18238 from 10110346/lx-wip-0608.

## What changes were proposed in this pull request?

This adds the average hash map probe metrics to hash aggregate.

`BytesToBytesMap` already has API to get the metrics, this PR adds an API to `UnsafeFixedWidthAggregationMap` to access it.

Preparing a test for this metrics seems tricky, because we don't know what collision keys are. For now, the test case generates random data large enough to have desired probe.

TODO in later PR: add hash map metrics to join.

## How was this patch tested?

Added test to SQLMetricsSuite.

Author: Liang-Chi Hsieh <viirya@gmail.com>

Closes #18258 from viirya/SPARK-20953.

## What changes were proposed in this pull request?
To use treeAggregate instead of aggregate in DataFrame.stat.bloomFilter to parallelize the operation of merging the bloom filters
(Please fill in changes proposed in this fix)

## How was this patch tested?
unit tests passed
(Please explain how this patch was tested. E.g. unit tests, integration tests, manual tests)
(If this patch involves UI changes, please attach a screenshot; otherwise, remove this)

Please review http://spark.apache.org/contributing.html before opening a pull request.

Author: Rishabh Bhardwaj <rbnext29@gmail.com>
Author: Rishabh Bhardwaj <admin@rishabh.local>
Author: Rishabh Bhardwaj <r0b00ko@rishabh.Dlink>
Author: Rishabh Bhardwaj <admin@Admins-MacBook-Pro.local>
Author: Rishabh Bhardwaj <r0b00ko@rishabh.local>

Closes #18263 from rishabhbhardwaj/SPARK-21039.

## What changes were proposed in this pull request?

Don't leave thread pool running from AlterTableRecoverPartitionsCommand DDL command

## How was this patch tested?

Existing tests.

Author: Sean Owen <sowen@cloudera.com>

Closes #18216 from srowen/SPARK-20920.

## What changes were proposed in this pull request?

Since `stack` function generates a table with nullable columns, it should allow mixed null values.

```scala
scala> sql("select stack(3, 1, 2, 3)").printSchema
root
 |-- col0: integer (nullable = true)

scala> sql("select stack(3, 1, 2, null)").printSchema
org.apache.spark.sql.AnalysisException: cannot resolve 'stack(3, 1, 2, NULL)' due to data type mismatch: Argument 1 (IntegerType) != Argument 3 (NullType); line 1 pos 7;
```

## How was this patch tested?

Pass the Jenkins with a new test case.

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #17251 from dongjoon-hyun/SPARK-19910.

This reverts commit 22dd65f5.

## What changes were proposed in this pull request?

This PR adds RateSource for Structured Streaming so that the user can use it to generate data for tests and benchmark easily.

This source generates increment long values with timestamps. Each generated row has two columns: a timestamp column for the generated time and an auto increment long column starting with 0L.

It supports the following options:
- `rowsPerSecond` (e.g. 100, default: 1): How many rows should be generated per second.
- `rampUpTime` (e.g. 5s, default: 0s): How long to ramp up before the generating speed becomes `rowsPerSecond`. Using finer granularities than seconds will be truncated to integer seconds.
- `numPartitions` (e.g. 10, default: Spark's default parallelism): The partition number for the generated rows. The source will try its best to reach `rowsPerSecond`, but the query may be resource constrained, and `numPartitions` can be tweaked to help reach the desired speed.

Here is a simple example that prints 10 rows per seconds:
```
    spark.readStream
      .format("rate")
      .option("rowsPerSecond", "10")
      .load()
      .writeStream
      .format("console")
      .start()
```

The idea came from marmbrus and he did the initial work.

## How was this patch tested?

The added tests.

Author: Shixiong Zhu <shixiong@databricks.com>
Author: Michael Armbrust <michael@databricks.com>

Closes #18199 from zsxwing/rate.

## What changes were proposed in this pull request?
This patch fixes a bug that can cause NullPointerException in LikeSimplification, when the pattern for like is null.

## How was this patch tested?
Added a new unit test case in LikeSimplificationSuite.

Author: Reynold Xin <rxin@databricks.com>

Closes #18273 from rxin/SPARK-21059.

## What changes were proposed in this pull request?

[SPARK-5100](https://github.com/apache/spark/commit/343d3bfafd449a0371feb6a88f78e07302fa7143) added Spark Thrift Server(STS) UI and the following logic to handle exceptions on case `Throwable`.

```scala
HiveThriftServer2.listener.onStatementError(
  statementId, e.getMessage, SparkUtils.exceptionString(e))
```

However, there occurred a missed case after implementing [SPARK-6964](https://github.com/apache/spark/commit/eb19d3f75cbd002f7e72ce02017a8de67f562792)'s `Support Cancellation in the Thrift Server` by adding case `HiveSQLException` before case `Throwable`.

```scala
case e: HiveSQLException =>
  if (getStatus().getState() == OperationState.CANCELED) {
    return
  } else {
    setState(OperationState.ERROR)
    throw e
  }
  // Actually do need to catch Throwable as some failures don't inherit from Exception and
  // HiveServer will silently swallow them.
case e: Throwable =>
  val currentState = getStatus().getState()
  logError(s"Error executing query, currentState $currentState, ", e)
  setState(OperationState.ERROR)
  HiveThriftServer2.listener.onStatementError(
    statementId, e.getMessage, SparkUtils.exceptionString(e))
  throw new HiveSQLException(e.toString)
```

Logically, we had better add `HiveThriftServer2.listener.onStatementError` on case `HiveSQLException`, too.

## How was this patch tested?

N/A

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #17643 from dongjoon-hyun/SPARK-20345.

The PR contains a tiny change to fix the way Spark parses string literals into timestamps. Currently, some timestamps that contain nanoseconds are corrupted during the conversion from internal UTF8Strings into the internal representation of timestamps.

Consider the following example:
```
spark.sql("SELECT cast('2015-01-02 00:00:00.000000001' as TIMESTAMP)").show(false)
+------------------------------------------------+
|CAST(2015-01-02 00:00:00.000000001 AS TIMESTAMP)|
+------------------------------------------------+
|2015-01-02 00:00:00.000001                      |
+------------------------------------------------+
```

The fix was tested with existing tests. Also, there is a new test to cover cases that did not work previously.

Author: aokolnychyi <anton.okolnychyi@sap.com>

Closes #18252 from aokolnychyi/spark-17914.

## What changes were proposed in this pull request?

Currently when a `ColumnVector` stores array type elements, we will use 2 arrays for lengths and offsets and implement them individually in on-heap and off-heap column vector.

In this PR, we use one array to represent both offsets and lengths, so that we can treat it as `ColumnVector` and all the logic can go to the base class `ColumnVector`

## How was this patch tested?

existing tests.

Author: Wenchen Fan <wenchen@databricks.com>

Closes #18260 from cloud-fan/put.