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985 commits

Author SHA1 Message Date
HyukjinKwon 6ab29b37cf [SPARK-32179][SPARK-32188][PYTHON][DOCS] Replace and redesign the documentation base
### What changes were proposed in this pull request?

This PR proposes to redesign the PySpark documentation.

I made a demo site to make it easier to review: https://hyukjin-spark.readthedocs.io/en/stable/reference/index.html.

Here is the initial draft for the final PySpark docs shape: https://hyukjin-spark.readthedocs.io/en/latest/index.html.

In more details, this PR proposes:
1. Use [pydata_sphinx_theme](https://github.com/pandas-dev/pydata-sphinx-theme) theme - [pandas](https://pandas.pydata.org/docs/) and [Koalas](https://koalas.readthedocs.io/en/latest/) use this theme. The CSS overwrite is ported from Koalas. The colours in the CSS were actually chosen by designers to use in Spark.
2. Use the Sphinx option to separate `source` and `build` directories as the documentation pages will likely grow.
3. Port current API documentation into the new style. It mimics Koalas and pandas to use the theme most effectively.

    One disadvantage of this approach is that you should list up APIs or classes; however, I think this isn't a big issue in PySpark since we're being conservative on adding APIs. I also intentionally listed classes only instead of functions in ML and MLlib to make it relatively easier to manage.

### Why are the changes needed?

Often I hear the complaints, from the users, that current PySpark documentation is pretty messy to read - https://spark.apache.org/docs/latest/api/python/index.html compared other projects such as [pandas](https://pandas.pydata.org/docs/) and [Koalas](https://koalas.readthedocs.io/en/latest/).

It would be nicer if we can make it more organised instead of just listing all classes, methods and attributes to make it easier to navigate.

Also, the documentation has been there from almost the very first version of PySpark. Maybe it's time to update it.

### Does this PR introduce _any_ user-facing change?

Yes, PySpark API documentation will be redesigned.

### How was this patch tested?

Manually tested, and the demo site was made to show.

Closes #29188 from HyukjinKwon/SPARK-32179.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-07-27 17:49:21 +09:00
Takuya UESHIN 7b66882c9d [SPARK-32338][SQL][PYSPARK][FOLLOW-UP] Update slice to accept Column for start and length
### What changes were proposed in this pull request?

This is a follow-up of #29138 which added overload `slice` function to accept `Column` for `start` and `length` in Scala.

This PR is updating the equivalent Python function to accept `Column` as well.

### Why are the changes needed?

Now that Scala version accepts `Column`, Python version should also accept it.

### Does this PR introduce _any_ user-facing change?

Yes, PySpark users will also be able to pass Column object to `start` and `length` parameter in `slice` function.

### How was this patch tested?

Added tests.

Closes #29195 from ueshin/issues/SPARK-32338/slice.

Authored-by: Takuya UESHIN <ueshin@databricks.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-07-23 13:53:50 +09:00
zero323 ef3cad17a6 [SPARK-29157][SQL][PYSPARK] Add DataFrameWriterV2 to Python API
### What changes were proposed in this pull request?

- Adds `DataFramWriterV2` class.
- Adds `writeTo` method to `pyspark.sql.DataFrame`.
- Adds related SQL partitioning functions (`years`, `months`, ..., `bucket`).

### Why are the changes needed?

Feature parity.

### Does this PR introduce any user-facing change?

No.

### How was this patch tested?

Added new unit tests.

TODO: Should we test against `org.apache.spark.sql.connector.InMemoryTableCatalog`? If so, how to expose it in Python tests?

Closes #27331 from zero323/SPARK-29157.

Authored-by: zero323 <mszymkiewicz@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-07-20 10:42:33 +09:00
Erik Krogen cf22d947fb [SPARK-32036] Replace references to blacklist/whitelist language with more appropriate terminology, excluding the blacklisting feature
### What changes were proposed in this pull request?

This PR will remove references to these "blacklist" and "whitelist" terms besides the blacklisting feature as a whole, which can be handled in a separate JIRA/PR.

This touches quite a few files, but the changes are straightforward (variable/method/etc. name changes) and most quite self-contained.

### Why are the changes needed?

As per discussion on the Spark dev list, it will be beneficial to remove references to problematic language that can alienate potential community members. One such reference is "blacklist" and "whitelist". While it seems to me that there is some valid debate as to whether these terms have racist origins, the cultural connotations are inescapable in today's world.

### Does this PR introduce _any_ user-facing change?

In the test file `HiveQueryFileTest`, a developer has the ability to specify the system property `spark.hive.whitelist` to specify a list of Hive query files that should be tested. This system property has been renamed to `spark.hive.includelist`. The old property has been kept for compatibility, but will log a warning if used. I am open to feedback from others on whether keeping a deprecated property here is unnecessary given that this is just for developers running tests.

### How was this patch tested?

Existing tests should be suitable since no behavior changes are expected as a result of this PR.

Closes #28874 from xkrogen/xkrogen-SPARK-32036-rename-blacklists.

Authored-by: Erik Krogen <ekrogen@linkedin.com>
Signed-off-by: Thomas Graves <tgraves@apache.org>
2020-07-15 11:40:55 -05:00
HyukjinKwon 676d92ecce [SPARK-32301][PYTHON][TESTS] Add a test case for toPandas to work with empty partitioned Spark DataFrame
### What changes were proposed in this pull request?

This PR proposes to port the test case from https://github.com/apache/spark/pull/29098 to branch-3.0 and master.  In the master and branch-3.0, this was fixed together at ecaa495b1f but no partition case is not being tested.

### Why are the changes needed?

To improve test coverage.

### Does this PR introduce _any_ user-facing change?

No, test-only.

### How was this patch tested?

Unit test was forward-ported.

Closes #29099 from HyukjinKwon/SPARK-32300-1.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-07-15 08:44:48 +09:00
Fokko Driesprong c602d79f89 [SPARK-32311][PYSPARK][TESTS] Remove duplicate import
### What changes were proposed in this pull request?

`datetime` is already imported a few lines below :)

ce27cc54c1/python/pyspark/sql/tests/test_pandas_udf_scalar.py (L24)

### Why are the changes needed?

This is the last instance of the duplicate import.

### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

Manual.

Closes #29109 from Fokko/SPARK-32311.

Authored-by: Fokko Driesprong <fokko@apache.org>
Signed-off-by: Dongjoon Hyun <dongjoon@apache.org>
2020-07-14 12:46:11 -07:00
HyukjinKwon 4ad9bfd53b [SPARK-32138] Drop Python 2.7, 3.4 and 3.5
### What changes were proposed in this pull request?

This PR aims to drop Python 2.7, 3.4 and 3.5.

Roughly speaking, it removes all the widely known Python 2 compatibility workarounds such as `sys.version` comparison, `__future__`. Also, it removes the Python 2 dedicated codes such as `ArrayConstructor` in Spark.

### Why are the changes needed?

 1. Unsupport EOL Python versions
 2. Reduce maintenance overhead and remove a bit of legacy codes and hacks for Python 2.
 3. PyPy2 has a critical bug that causes a flaky test, SPARK-28358 given my testing and investigation.
 4. Users can use Python type hints with Pandas UDFs without thinking about Python version
 5. Users can leverage one latest cloudpickle, https://github.com/apache/spark/pull/28950. With Python 3.8+ it can also leverage C pickle.

### Does this PR introduce _any_ user-facing change?

Yes, users cannot use Python 2.7, 3.4 and 3.5 in the upcoming Spark version.

### How was this patch tested?

Manually tested and also tested in Jenkins.

Closes #28957 from HyukjinKwon/SPARK-32138.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-07-14 11:22:44 +09:00
HyukjinKwon b84ed4146d [SPARK-32245][INFRA] Run Spark tests in Github Actions
### What changes were proposed in this pull request?

This PR aims to run the Spark tests in Github Actions.

To briefly explain the main idea:

- Reuse `dev/run-tests.py` with SBT build
- Reuse the modules in `dev/sparktestsupport/modules.py` to test each module
- Pass the modules to test into `dev/run-tests.py` directly via `TEST_ONLY_MODULES` environment variable. For example, `pyspark-sql,core,sql,hive`.
- `dev/run-tests.py` _does not_ take the dependent modules into account but solely the specified modules to test.

Another thing to note might be `SlowHiveTest` annotation. Running the tests in Hive modules takes too much so the slow tests are extracted and it runs as a separate job. It was extracted from the actual elapsed time in Jenkins:

![Screen Shot 2020-07-09 at 7 48 13 PM](https://user-images.githubusercontent.com/6477701/87050238-f6098e80-c238-11ea-9c4a-ab505af61381.png)

So, Hive tests are separated into to jobs. One is slow test cases, and the other one is the other test cases.

_Note that_ the current GitHub Actions build virtually copies what the default PR builder on Jenkins does (without other profiles such as JDK 11, Hadoop 2, etc.). The only exception is Kinesis https://github.com/apache/spark/pull/29057/files#diff-04eb107ee163a50b61281ca08f4e4c7bR23

### Why are the changes needed?

Last week and onwards, the Jenkins machines became very unstable for many reasons:
  - Apparently, the machines became extremely slow. Almost all tests can't pass.
  - One machine (worker 4) started to have the corrupt `.m2` which fails the build.
  - Documentation build fails time to time for an unknown reason in Jenkins machine specifically. This is disabled for now at https://github.com/apache/spark/pull/29017.
  - Almost all PRs are basically blocked by this instability currently.

The advantages of using Github Actions:
  - To avoid depending on few persons who can access to the cluster.
  - To reduce the elapsed time in the build - we could split the tests (e.g., SQL, ML, CORE), and run them in parallel so the total build time will significantly reduce.
  - To control the environment more flexibly.
  - Other contributors can test and propose to fix Github Actions configurations so we can distribute this build management cost.

Note that:
- The current build in Jenkins takes _more than 7 hours_. With Github actions it takes _less than 2 hours_
- We can now control the environments especially for Python easily.
- The test and build look more stable than the Jenkins'.

### Does this PR introduce _any_ user-facing change?

No, dev-only change.

### How was this patch tested?

Tested at https://github.com/HyukjinKwon/spark/pull/4

Closes #29057 from HyukjinKwon/migrate-to-github-actions.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: Dongjoon Hyun <dongjoon@apache.org>
2020-07-11 13:09:06 -07:00
HyukjinKwon 01e9dd9050 [SPARK-20680][SQL][FOLLOW-UP] Revert NullType.simpleString from 'unknown' to 'null'
### What changes were proposed in this pull request?

This PR proposes to partially reverts the simple string in `NullType` at https://github.com/apache/spark/pull/28833: `NullType.simpleString` back from `unknown` to `null`.

### Why are the changes needed?

- Technically speaking, it's orthogonal with the issue itself, SPARK-20680.
- It needs some more discussion, see https://github.com/apache/spark/pull/28833#issuecomment-655277714

### Does this PR introduce _any_ user-facing change?

It reverts back the user-facing changes at https://github.com/apache/spark/pull/28833.
The simple string of `NullType` is back to `null`.

### How was this patch tested?

I just logically reverted. Jenkins should test it out.

Closes #29041 from HyukjinKwon/SPARK-20680.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: Dongjoon Hyun <dongjoon@apache.org>
2020-07-09 19:44:08 -07:00
LantaoJin b5297c43b0 [SPARK-20680][SQL] Spark-sql do not support for creating table with void column datatype
### What changes were proposed in this pull request?

This is the new PR which to address the close one #17953

1. support "void" primitive data type in the `AstBuilder`, point it to `NullType`
2. forbid creating tables with VOID/NULL column type

### Why are the changes needed?

1. Spark is incompatible with hive void type. When Hive table schema contains void type, DESC table will throw an exception in Spark.

>hive> create table bad as select 1 x, null z from dual;
>hive> describe bad;
OK
x	int
z	void

In Spark2.0.x, the behaviour to read this view is normal:
>spark-sql> describe bad;
x       int     NULL
z       void    NULL
Time taken: 4.431 seconds, Fetched 2 row(s)

But in lastest Spark version, it failed with SparkException: Cannot recognize hive type string: void

>spark-sql> describe bad;
17/05/09 03:12:08 ERROR thriftserver.SparkSQLDriver: Failed in [describe bad]
org.apache.spark.SparkException: Cannot recognize hive type string: void
Caused by: org.apache.spark.sql.catalyst.parser.ParseException:
DataType void() is not supported.(line 1, pos 0)
== SQL ==
void
^^^
        ... 61 more
org.apache.spark.SparkException: Cannot recognize hive type string: void

2. Hive CTAS statements throws error when select clause has NULL/VOID type column since HIVE-11217
In Spark, creating table with a VOID/NULL column should throw readable exception message, include

- create data source table (using parquet, json, ...)
- create hive table (with or without stored as)
- CTAS

### Does this PR introduce any user-facing change?

No

### How was this patch tested?

Add unit tests

Closes #28833 from LantaoJin/SPARK-20680_COPY.

Authored-by: LantaoJin <jinlantao@gmail.com>
Signed-off-by: Dongjoon Hyun <dongjoon@apache.org>
2020-07-07 18:58:01 -07:00
Bryan Cutler 1d1809636b [SPARK-32162][PYTHON][TESTS] Improve error message of Pandas grouped map test with window
### What changes were proposed in this pull request?

Improve the error message in test GroupedMapInPandasTests.test_grouped_over_window_with_key to show the incorrect values.

### Why are the changes needed?

This test failure has come up often in Arrow testing because it tests a struct  with timestamp values through a Pandas UDF. The current error message is not helpful as it doesn't show the incorrect values, only that it failed. This change will instead raise an assertion error with the incorrect values on a failure.

Before:

```
======================================================================
FAIL: test_grouped_over_window_with_key (pyspark.sql.tests.test_pandas_grouped_map.GroupedMapInPandasTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/spark/python/pyspark/sql/tests/test_pandas_grouped_map.py", line 588, in test_grouped_over_window_with_key
    self.assertTrue(all([r[0] for r in result]))
AssertionError: False is not true
```

After:
```
======================================================================
ERROR: test_grouped_over_window_with_key (pyspark.sql.tests.test_pandas_grouped_map.GroupedMapInPandasTests)
----------------------------------------------------------------------
...
AssertionError: {'start': datetime.datetime(2018, 3, 20, 0, 0), 'end': datetime.datetime(2018, 3, 25, 0, 0)}, != {'start': datetime.datetime(2020, 3, 20, 0, 0), 'end': datetime.datetime(2020, 3, 25, 0, 0)}
```

### Does this PR introduce _any_ user-facing change?

No

### How was this patch tested?

Improved existing test

Closes #28987 from BryanCutler/pandas-grouped-map-test-output-SPARK-32162.

Authored-by: Bryan Cutler <cutlerb@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-07-06 21:39:41 +09:00
animenon 45fe6b62a7 [MINOR][DOCS] Pyspark getActiveSession docstring
### What changes were proposed in this pull request?

Minor fix so that the documentation of `getActiveSession` is fixed.
The sample code snippet doesn't come up formatted rightly, added spacing for this to be fixed.
Also added return to docs.

### Why are the changes needed?

The sample code is getting mixed up as description in the docs.

[Current Doc Link](http://spark.apache.org/docs/latest/api/python/pyspark.sql.html?highlight=getactivesession#pyspark.sql.SparkSession.getActiveSession)

![image](https://user-images.githubusercontent.com/6907950/86331522-d7b6f800-bc66-11ea-998c-42085f5e5b04.png)

### Does this PR introduce _any_ user-facing change?

Yes, documentation of getActiveSession is fixed.
And added description about return.

### How was this patch tested?

Adding a spacing between description and code seems to fix the issue.

Closes #28978 from animenon/docs_minor.

Authored-by: animenon <animenon@mail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-07-02 21:02:00 +09:00
Max Gekk dd03c31ea5 [SPARK-32088][PYTHON][FOLLOWUP] Replace collect() by show() in the example for timestamp_seconds
### What changes were proposed in this pull request?
Modify the example for `timestamp_seconds` and replace `collect()` by `show()`.

### Why are the changes needed?
The SQL config `spark.sql.session.timeZone` doesn't influence on the `collect` in the example. The code below demonstrates that:
```
$ export TZ="UTC"
```
```python
>>> from pyspark.sql.functions import timestamp_seconds
>>> spark.conf.set("spark.sql.session.timeZone", "America/Los_Angeles")
>>> time_df = spark.createDataFrame([(1230219000,)], ['unix_time'])
>>> time_df.select(timestamp_seconds(time_df.unix_time).alias('ts')).collect()
[Row(ts=datetime.datetime(2008, 12, 25, 15, 30))]
```
The expected time is **07:30 but we get 15:30**.

### Does this PR introduce _any_ user-facing change?
No

### How was this patch tested?
By running the modified example via:
```
$ ./python/run-tests --modules=pyspark-sql
```

Closes #28959 from MaxGekk/SPARK-32088-fix-timezone-issue-followup.

Authored-by: Max Gekk <max.gekk@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-07-01 13:17:49 +09:00
GuoPhilipse ac3a0551d8 [SPARK-32088][PYTHON] Pin the timezone in timestamp_seconds doctest
### What changes were proposed in this pull request?

Add American timezone during timestamp_seconds doctest

### Why are the changes needed?

`timestamp_seconds` doctest in `functions.py` used default timezone to get expected result
For example:

```python
>>> time_df = spark.createDataFrame([(1230219000,)], ['unix_time'])
>>> time_df.select(timestamp_seconds(time_df.unix_time).alias('ts')).collect()
[Row(ts=datetime.datetime(2008, 12, 25, 7, 30))]
```

But when we have a non-american timezone, the test case will get different test result.

For example, when we set current timezone as `Asia/Shanghai`, the test result will be

```
[Row(ts=datetime.datetime(2008, 12, 25, 23, 30))]
```

So no matter where we run the test case ,we will always get the expected permanent result if we set the timezone on one specific area.

### Does this PR introduce _any_ user-facing change?

No

### How was this patch tested?

Unit test

Closes #28932 from GuoPhilipse/SPARK-32088-fix-timezone-issue.

Lead-authored-by: GuoPhilipse <46367746+GuoPhilipse@users.noreply.github.com>
Co-authored-by: GuoPhilipse <guofei_ok@126.com>
Signed-off-by: Dongjoon Hyun <dongjoon@apache.org>
2020-06-26 19:06:31 -07:00
HyukjinKwon 1af19a7b68 [SPARK-32098][PYTHON] Use iloc for positional slicing instead of direct slicing in createDataFrame with Arrow
### What changes were proposed in this pull request?

When you use floats are index of pandas, it creates a Spark DataFrame with a wrong results as below when Arrow is enabled:

```bash
./bin/pyspark --conf spark.sql.execution.arrow.pyspark.enabled=true
```

```python
>>> import pandas as pd
>>> spark.createDataFrame(pd.DataFrame({'a': [1,2,3]}, index=[2., 3., 4.])).show()
+---+
|  a|
+---+
|  1|
|  1|
|  2|
+---+
```

This is because direct slicing uses the value as index when the index contains floats:

```python
>>> pd.DataFrame({'a': [1,2,3]}, index=[2., 3., 4.])[2:]
     a
2.0  1
3.0  2
4.0  3
>>> pd.DataFrame({'a': [1,2,3]}, index=[2., 3., 4.]).iloc[2:]
     a
4.0  3
>>> pd.DataFrame({'a': [1,2,3]}, index=[2, 3, 4])[2:]
   a
4  3
```

This PR proposes to explicitly use `iloc` to positionally slide when we create a DataFrame from a pandas DataFrame with Arrow enabled.

FWIW, I was trying to investigate why direct slicing refers the index value or the positional index sometimes but I stopped investigating further after reading this https://pandas.pydata.org/pandas-docs/stable/getting_started/10min.html#selection

> While standard Python / Numpy expressions for selecting and setting are intuitive and come in handy for interactive work, for production code, we recommend the optimized pandas data access methods, `.at`, `.iat`, `.loc` and `.iloc`.

### Why are the changes needed?

To create the correct Spark DataFrame from a pandas DataFrame without a data loss.

### Does this PR introduce _any_ user-facing change?

Yes, it is a bug fix.

```bash
./bin/pyspark --conf spark.sql.execution.arrow.pyspark.enabled=true
```
```python
import pandas as pd
spark.createDataFrame(pd.DataFrame({'a': [1,2,3]}, index=[2., 3., 4.])).show()
```

Before:

```
+---+
|  a|
+---+
|  1|
|  1|
|  2|
+---+
```

After:

```
+---+
|  a|
+---+
|  1|
|  2|
|  3|
+---+
```

### How was this patch tested?

Manually tested and unittest were added.

Closes #28928 from HyukjinKwon/SPARK-32098.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: Bryan Cutler <cutlerb@gmail.com>
2020-06-25 11:04:47 -07:00
GuoPhilipse f0e6d0ec13 [SPARK-31710][SQL] Fail casting numeric to timestamp by default
## What changes were proposed in this pull request?
we fail casting from numeric to timestamp by default.

## Why are the changes needed?
casting from numeric to timestamp is not a  non-standard,meanwhile it may generate different result between spark and other systems,for example hive

## Does this PR introduce any user-facing change?
Yes,user cannot cast numeric to timestamp directly,user have to use the following function to achieve the same effect:TIMESTAMP_SECONDS/TIMESTAMP_MILLIS/TIMESTAMP_MICROS

## How was this patch tested?
unit test added

Closes #28593 from GuoPhilipse/31710-fix-compatibility.

Lead-authored-by: GuoPhilipse <guofei_ok@126.com>
Co-authored-by: GuoPhilipse <46367746+GuoPhilipse@users.noreply.github.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2020-06-16 08:35:35 +00:00
HyukjinKwon 56264fb5d3 [SPARK-31965][TESTS][PYTHON] Move doctests related to Java function registration to test conditionally
### What changes were proposed in this pull request?

This PR proposes to move the doctests in `registerJavaUDAF` and `registerJavaFunction` to the proper unittests that run conditionally when the test classes are present.

Both tests are dependent on the test classes in JVM side, `test.org.apache.spark.sql.JavaStringLength` and `test.org.apache.spark.sql.MyDoubleAvg`. So if you run the tests against the plain `sbt package`, it fails as below:

```
**********************************************************************
File "/.../spark/python/pyspark/sql/udf.py", line 366, in pyspark.sql.udf.UDFRegistration.registerJavaFunction
Failed example:
    spark.udf.registerJavaFunction(
        "javaStringLength", "test.org.apache.spark.sql.JavaStringLength", IntegerType())
Exception raised:
    Traceback (most recent call last):
   ...
test.org.apache.spark.sql.JavaStringLength, please make sure it is on the classpath;
...
   6 of   7 in pyspark.sql.udf.UDFRegistration.registerJavaFunction
   2 of   4 in pyspark.sql.udf.UDFRegistration.registerJavaUDAF
***Test Failed*** 8 failures.
```

### Why are the changes needed?

In order to support to run the tests against the plain SBT build. See also https://spark.apache.org/developer-tools.html

### Does this PR introduce _any_ user-facing change?

No, it's test-only.

### How was this patch tested?

Manually tested as below:

```bash
./build/sbt -DskipTests -Phive-thriftserver clean package
cd python
./run-tests --python-executable=python3 --testname="pyspark.sql.udf UserDefinedFunction"
./run-tests --python-executable=python3 --testname="pyspark.sql.tests.test_udf UDFTests"
```

```bash
./build/sbt -DskipTests -Phive-thriftserver clean test:package
cd python
./run-tests --python-executable=python3 --testname="pyspark.sql.udf UserDefinedFunction"
./run-tests --python-executable=python3 --testname="pyspark.sql.tests.test_udf UDFTests"
```

Closes #28795 from HyukjinKwon/SPARK-31965.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: Dongjoon Hyun <dongjoon@apache.org>
2020-06-10 21:15:40 -07:00
Bryan Cutler b7ef5294f1 [SPARK-31964][PYTHON] Use Pandas is_categorical on Arrow category type conversion
### What changes were proposed in this pull request?

When using pyarrow to convert a Pandas categorical column, use `is_categorical` instead of trying to import `CategoricalDtype`

### Why are the changes needed?

The import for `CategoricalDtype` had changed from Pandas 0.23 to 1.0 and pyspark currently tries both locations. Using `is_categorical` is a more stable API.

### Does this PR introduce _any_ user-facing change?

No

### How was this patch tested?

Existing tests

Closes #28793 from BryanCutler/arrow-use-is_categorical-SPARK-31964.

Authored-by: Bryan Cutler <cutlerb@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-06-11 10:26:40 +09:00
HyukjinKwon 00d06cad56 [SPARK-31915][SQL][PYTHON] Resolve the grouping column properly per the case sensitivity in grouped and cogrouped pandas UDFs
### What changes were proposed in this pull request?

This is another approach to fix the issue. See the previous try https://github.com/apache/spark/pull/28745. It was too invasive so I took more conservative approach.

This PR proposes to resolve grouping attributes separately first so it can be properly referred when `FlatMapGroupsInPandas` and `FlatMapCoGroupsInPandas` are resolved without ambiguity.

Previously,

```python
from pyspark.sql.functions import *
df = spark.createDataFrame([[1, 1]], ["column", "Score"])
pandas_udf("column integer, Score float", PandasUDFType.GROUPED_MAP)
def my_pandas_udf(pdf):
    return pdf.assign(Score=0.5)

df.groupby('COLUMN').apply(my_pandas_udf).show()
```

was failed as below:

```
pyspark.sql.utils.AnalysisException: "Reference 'COLUMN' is ambiguous, could be: COLUMN, COLUMN.;"
```
because the unresolved `COLUMN` in `FlatMapGroupsInPandas` doesn't know which reference to take from the child projection.

After this fix, it resolves the child projection first with grouping keys and pass, to `FlatMapGroupsInPandas`, the attribute as a grouping key from the child projection that is positionally selected.

### Why are the changes needed?

To resolve grouping keys correctly.

### Does this PR introduce _any_ user-facing change?

Yes,

```python
from pyspark.sql.functions import *
df = spark.createDataFrame([[1, 1]], ["column", "Score"])
pandas_udf("column integer, Score float", PandasUDFType.GROUPED_MAP)
def my_pandas_udf(pdf):
    return pdf.assign(Score=0.5)

df.groupby('COLUMN').apply(my_pandas_udf).show()
```

```python
df1 = spark.createDataFrame([(1, 1)], ("column", "value"))
df2 = spark.createDataFrame([(1, 1)], ("column", "value"))

df1.groupby("COLUMN").cogroup(
    df2.groupby("COLUMN")
).applyInPandas(lambda r, l: r + l, df1.schema).show()
```

Before:

```
pyspark.sql.utils.AnalysisException: Reference 'COLUMN' is ambiguous, could be: COLUMN, COLUMN.;
```

```
pyspark.sql.utils.AnalysisException: cannot resolve '`COLUMN`' given input columns: [COLUMN, COLUMN, value, value];;
'FlatMapCoGroupsInPandas ['COLUMN], ['COLUMN], <lambda>(column#9L, value#10L, column#13L, value#14L), [column#22L, value#23L]
:- Project [COLUMN#9L, column#9L, value#10L]
:  +- LogicalRDD [column#9L, value#10L], false
+- Project [COLUMN#13L, column#13L, value#14L]
   +- LogicalRDD [column#13L, value#14L], false
```

After:

```
+------+-----+
|column|Score|
+------+-----+
|     1|  0.5|
+------+-----+
```

```
+------+-----+
|column|value|
+------+-----+
|     2|    2|
+------+-----+
```

### How was this patch tested?

Unittests were added and manually tested.

Closes #28777 from HyukjinKwon/SPARK-31915-another.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: Bryan Cutler <cutlerb@gmail.com>
2020-06-10 15:54:07 -07:00
William Hyun 2ab82fae57 [SPARK-31963][PYSPARK][SQL] Support both pandas 0.23 and 1.0 in serializers.py
### What changes were proposed in this pull request?

This PR aims to support both pandas 0.23 and 1.0.

### Why are the changes needed?
```
$ pip install pandas==0.23.2

$ python -c "import pandas.CategoricalDtype"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
ModuleNotFoundError: No module named 'pandas.CategoricalDtype'

$ python -c "from pandas.api.types import CategoricalDtype"
```
### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

Pass the Jenkins.
```
$ pip freeze | grep pandas
pandas==0.23.2

$ python/run-tests.py --python-executables python --modules pyspark-sql
...
Tests passed in 359 seconds
```

Closes #28789 from williamhyun/williamhyun-patch-2.

Authored-by: William Hyun <williamhyun3@gmail.com>
Signed-off-by: Dongjoon Hyun <dongjoon@apache.org>
2020-06-10 14:42:45 -07:00
Takuya UESHIN 032d17933b [SPARK-31945][SQL][PYSPARK] Enable cache for the same Python function
### What changes were proposed in this pull request?

This PR proposes to make `PythonFunction` holds `Seq[Byte]` instead of `Array[Byte]` to be able to compare if the byte array has the same values for the cache manager.

### Why are the changes needed?

Currently the cache manager doesn't use the cache for `udf` if the `udf` is created again even if the functions is the same.

```py
>>> func = lambda x: x

>>> df = spark.range(1)
>>> df.select(udf(func)("id")).cache()
```
```py
>>> df.select(udf(func)("id")).explain()
== Physical Plan ==
*(2) Project [pythonUDF0#14 AS <lambda>(id)#12]
+- BatchEvalPython [<lambda>(id#0L)], [pythonUDF0#14]
 +- *(1) Range (0, 1, step=1, splits=12)
```

This is because `PythonFunction` holds `Array[Byte]`, and `equals` method of array equals only when the both array is the same instance.

### Does this PR introduce _any_ user-facing change?

Yes, if the user reuse the Python function for the UDF, the cache manager will detect the same function and use the cache for it.

### How was this patch tested?

I added a test case and manually.

```py
>>> df.select(udf(func)("id")).explain()
== Physical Plan ==
InMemoryTableScan [<lambda>(id)#12]
   +- InMemoryRelation [<lambda>(id)#12], StorageLevel(disk, memory, deserialized, 1 replicas)
         +- *(2) Project [pythonUDF0#5 AS <lambda>(id)#3]
            +- BatchEvalPython [<lambda>(id#0L)], [pythonUDF0#5]
               +- *(1) Range (0, 1, step=1, splits=12)
```

Closes #28774 from ueshin/issues/SPARK-31945/udf_cache.

Authored-by: Takuya UESHIN <ueshin@databricks.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-06-10 16:38:59 +09:00
HyukjinKwon e28914095a [SPARK-31849][PYTHON][SQL][FOLLOW-UP] More correct error message in Python UDF exception message
### What changes were proposed in this pull request?

This PR proposes to fix wordings in the Python UDF exception error message from:

From:

> An exception was thrown from Python worker in the executor. The below is the Python worker stacktrace.

To:

> An exception was thrown from the Python worker. Please see the stack trace below.

It removes "executor" because Python worker is technically a separate process, and remove the duplicated wording "Python worker" .

### Why are the changes needed?

To give users better exception messages.

### Does this PR introduce _any_ user-facing change?

No, it's in unreleased branches only. If RC3 passes, yes, it will change the exception message.

### How was this patch tested?

Manually tested.

Closes #28762 from HyukjinKwon/SPARK-31849-followup-2.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-06-09 10:24:34 +09:00
HyukjinKwon a42af81706 [SPARK-31849][PYTHON][SQL][FOLLOW-UP] Deduplicate and reuse Utils.exceptionString in Python exception handling
### What changes were proposed in this pull request?

This PR proposes to use existing util `org.apache.spark.util.Utils.exceptionString` for the same codes at:

```python
    jwriter = jvm.java.io.StringWriter()
    e.printStackTrace(jvm.java.io.PrintWriter(jwriter))
    stacktrace = jwriter.toString()
```

### Why are the changes needed?

To deduplicate codes. Plus, less communication between JVM and Py4j.

### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

Manually tested.

Closes #28749 from HyukjinKwon/SPARK-31849-followup.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-06-08 15:18:42 +09:00
HyukjinKwon 53ce58da34 [MINOR][PYTHON] Add one more newline between JVM and Python tracebacks
### What changes were proposed in this pull request?

This PR proposes to add one more newline to clearly separate JVM and Python tracebacks:

Before:

```
Traceback (most recent call last):
  ...
pyspark.sql.utils.AnalysisException: Reference 'column' is ambiguous, could be: column, column.;
JVM stacktrace:
org.apache.spark.sql.AnalysisException: Reference 'column' is ambiguous, could be: column, column.;
  ...
```

After:

```
Traceback (most recent call last):
  ...
pyspark.sql.utils.AnalysisException: Reference 'column' is ambiguous, could be: column, column.;

JVM stacktrace:
org.apache.spark.sql.AnalysisException: Reference 'column' is ambiguous, could be: column, column.;
  ...
```

This is kind of a followup of e69466056f (SPARK-31849).

### Why are the changes needed?

To make it easier to read.

### Does this PR introduce _any_ user-facing change?

It's in the unreleased branches.

### How was this patch tested?

Manually tested.

Closes #28732 from HyukjinKwon/python-minor.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-06-05 13:31:35 +09:00
HyukjinKwon e1d5201140 [SPARK-31895][PYTHON][SQL] Support DataFrame.explain(extended: str) case to be consistent with Scala side
### What changes were proposed in this pull request?

Scala:

```scala
scala> spark.range(10).explain("cost")
```
```
== Optimized Logical Plan ==
Range (0, 10, step=1, splits=Some(12)), Statistics(sizeInBytes=80.0 B)

== Physical Plan ==
*(1) Range (0, 10, step=1, splits=12)
```

PySpark:

```python
>>> spark.range(10).explain("cost")
```
```
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/.../spark/python/pyspark/sql/dataframe.py", line 333, in explain
    raise TypeError(err_msg)
TypeError: extended (optional) should be provided as bool, got <class 'str'>
```

In addition, it is consistent with other codes too, for example, `DataFrame.sample` also can support `DataFrame.sample(1.0)` and `DataFrame.sample(False)`.

### Why are the changes needed?

To provide the consistent API support across APIs.

### Does this PR introduce _any_ user-facing change?

Nope, it's only changes in unreleased branches.
If this lands to master only, yes, users will be able to set `mode` as `df.explain("...")` in Spark 3.1.

After this PR:

```python
>>> spark.range(10).explain("cost")
```
```
== Optimized Logical Plan ==
Range (0, 10, step=1, splits=Some(12)), Statistics(sizeInBytes=80.0 B)

== Physical Plan ==
*(1) Range (0, 10, step=1, splits=12)
```

### How was this patch tested?

Unittest was added and manually tested as well to make sure:

```python
spark.range(10).explain(True)
spark.range(10).explain(False)
spark.range(10).explain("cost")
spark.range(10).explain(extended="cost")
spark.range(10).explain(mode="cost")
spark.range(10).explain()
spark.range(10).explain(True, "cost")
spark.range(10).explain(1.0)
```

Closes #28711 from HyukjinKwon/SPARK-31895.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-06-03 12:07:05 +09:00
HyukjinKwon e69466056f [SPARK-31849][PYTHON][SQL] Make PySpark SQL exceptions more Pythonic
### What changes were proposed in this pull request?

This PR proposes to make PySpark exception more Pythonic by hiding JVM stacktrace by default. It can be enabled by turning on `spark.sql.pyspark.jvmStacktrace.enabled` configuration.

```
Traceback (most recent call last):
  ...
pyspark.sql.utils.PythonException:
  An exception was thrown from Python worker in the executor. The below is the Python worker stacktrace.
Traceback (most recent call last):
  ...
```

If this `spark.sql.pyspark.jvmStacktrace.enabled` is enabled, it appends:

```
JVM stacktrace:
org.apache.spark.Exception: ...
  ...
```

For example, the codes below:

```python
from pyspark.sql.functions import udf
udf
def divide_by_zero(v):
    raise v / 0

spark.range(1).select(divide_by_zero("id")).show()
```

will show an error messages that looks like Python exception thrown from the local.

<details>
<summary>Python exception message when <code>spark.sql.pyspark.jvmStacktrace.enabled</code> is off (default)</summary>

```
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/.../spark/python/pyspark/sql/dataframe.py", line 427, in show
    print(self._jdf.showString(n, 20, vertical))
  File "/.../spark/python/lib/py4j-0.10.9-src.zip/py4j/java_gateway.py", line 1305, in __call__
  File "/.../spark/python/pyspark/sql/utils.py", line 131, in deco
    raise_from(converted)
  File "<string>", line 3, in raise_from
pyspark.sql.utils.PythonException:
  An exception was thrown from Python worker in the executor. The below is the Python worker stacktrace.
Traceback (most recent call last):
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 605, in main
    process()
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 597, in process
    serializer.dump_stream(out_iter, outfile)
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 223, in dump_stream
    self.serializer.dump_stream(self._batched(iterator), stream)
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 141, in dump_stream
    for obj in iterator:
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 212, in _batched
    for item in iterator:
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 450, in mapper
    result = tuple(f(*[a[o] for o in arg_offsets]) for (arg_offsets, f) in udfs)
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 450, in <genexpr>
    result = tuple(f(*[a[o] for o in arg_offsets]) for (arg_offsets, f) in udfs)
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 90, in <lambda>
    return lambda *a: f(*a)
  File "/.../spark/python/lib/pyspark.zip/pyspark/util.py", line 107, in wrapper
    return f(*args, **kwargs)
  File "<stdin>", line 3, in divide_by_zero
ZeroDivisionError: division by zero
```

</details>

<details>
<summary>Python exception message when <code>spark.sql.pyspark.jvmStacktrace.enabled</code> is on</summary>

```
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/.../spark/python/pyspark/sql/dataframe.py", line 427, in show
    print(self._jdf.showString(n, 20, vertical))
  File "/.../spark/python/lib/py4j-0.10.9-src.zip/py4j/java_gateway.py", line 1305, in __call__
  File "/.../spark/python/pyspark/sql/utils.py", line 137, in deco
    raise_from(converted)
  File "<string>", line 3, in raise_from
pyspark.sql.utils.PythonException:
  An exception was thrown from Python worker in the executor. The below is the Python worker stacktrace.
Traceback (most recent call last):
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 605, in main
    process()
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 597, in process
    serializer.dump_stream(out_iter, outfile)
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 223, in dump_stream
    self.serializer.dump_stream(self._batched(iterator), stream)
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 141, in dump_stream
    for obj in iterator:
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 212, in _batched
    for item in iterator:
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 450, in mapper
    result = tuple(f(*[a[o] for o in arg_offsets]) for (arg_offsets, f) in udfs)
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 450, in <genexpr>
    result = tuple(f(*[a[o] for o in arg_offsets]) for (arg_offsets, f) in udfs)
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 90, in <lambda>
    return lambda *a: f(*a)
  File "/.../spark/python/lib/pyspark.zip/pyspark/util.py", line 107, in wrapper
    return f(*args, **kwargs)
  File "<stdin>", line 3, in divide_by_zero
ZeroDivisionError: division by zero

JVM stacktrace:
org.apache.spark.SparkException: Job aborted due to stage failure: Task 0 in stage 1.0 failed 4 times, most recent failure: Lost task 0.3 in stage 1.0 (TID 4, 192.168.35.193, executor 0): org.apache.spark.api.python.PythonException: Traceback (most recent call last):
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 605, in main
    process()
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 597, in process
    serializer.dump_stream(out_iter, outfile)
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 223, in dump_stream
    self.serializer.dump_stream(self._batched(iterator), stream)
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 141, in dump_stream
    for obj in iterator:
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 212, in _batched
    for item in iterator:
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 450, in mapper
    result = tuple(f(*[a[o] for o in arg_offsets]) for (arg_offsets, f) in udfs)
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 450, in <genexpr>
    result = tuple(f(*[a[o] for o in arg_offsets]) for (arg_offsets, f) in udfs)
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 90, in <lambda>
    return lambda *a: f(*a)
  File "/.../spark/python/lib/pyspark.zip/pyspark/util.py", line 107, in wrapper
    return f(*args, **kwargs)
  File "<stdin>", line 3, in divide_by_zero
ZeroDivisionError: division by zero

	at org.apache.spark.api.python.BasePythonRunner$ReaderIterator.handlePythonException(PythonRunner.scala:516)
	at org.apache.spark.sql.execution.python.PythonUDFRunner$$anon$2.read(PythonUDFRunner.scala:81)
	at org.apache.spark.sql.execution.python.PythonUDFRunner$$anon$2.read(PythonUDFRunner.scala:64)
	at org.apache.spark.api.python.BasePythonRunner$ReaderIterator.hasNext(PythonRunner.scala:469)
	at org.apache.spark.InterruptibleIterator.hasNext(InterruptibleIterator.scala:37)
	at scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:489)
	at scala.collection.Iterator$$anon$10.hasNext(Iterator.scala:458)
	at scala.collection.Iterator$$anon$10.hasNext(Iterator.scala:458)
	at org.apache.spark.sql.catalyst.expressions.GeneratedClass$GeneratedIteratorForCodegenStage2.processNext(Unknown Source)
	at org.apache.spark.sql.execution.BufferedRowIterator.hasNext(BufferedRowIterator.java:43)
	at org.apache.spark.sql.execution.WholeStageCodegenExec$$anon$1.hasNext(WholeStageCodegenExec.scala:753)
	at org.apache.spark.sql.execution.SparkPlan.$anonfun$getByteArrayRdd$1(SparkPlan.scala:340)
	at org.apache.spark.rdd.RDD.$anonfun$mapPartitionsInternal$2(RDD.scala:898)
	at org.apache.spark.rdd.RDD.$anonfun$mapPartitionsInternal$2$adapted(RDD.scala:898)
	at org.apache.spark.rdd.MapPartitionsRDD.compute(MapPartitionsRDD.scala:52)
	at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:373)
	at org.apache.spark.rdd.RDD.iterator(RDD.scala:337)
	at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:90)
	at org.apache.spark.scheduler.Task.run(Task.scala:127)
	at org.apache.spark.executor.Executor$TaskRunner.$anonfun$run$3(Executor.scala:469)
	at org.apache.spark.util.Utils$.tryWithSafeFinally(Utils.scala:1377)
	at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:472)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)

Driver stacktrace:
	at org.apache.spark.scheduler.DAGScheduler.failJobAndIndependentStages(DAGScheduler.scala:2117)
	at org.apache.spark.scheduler.DAGScheduler.$anonfun$abortStage$2(DAGScheduler.scala:2066)
	at org.apache.spark.scheduler.DAGScheduler.$anonfun$abortStage$2$adapted(DAGScheduler.scala:2065)
	at scala.collection.mutable.ResizableArray.foreach(ResizableArray.scala:62)
	at scala.collection.mutable.ResizableArray.foreach$(ResizableArray.scala:55)
	at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:49)
	at org.apache.spark.scheduler.DAGScheduler.abortStage(DAGScheduler.scala:2065)
	at org.apache.spark.scheduler.DAGScheduler.$anonfun$handleTaskSetFailed$1(DAGScheduler.scala:1021)
	at org.apache.spark.scheduler.DAGScheduler.$anonfun$handleTaskSetFailed$1$adapted(DAGScheduler.scala:1021)
	at scala.Option.foreach(Option.scala:407)
	at org.apache.spark.scheduler.DAGScheduler.handleTaskSetFailed(DAGScheduler.scala:1021)
	at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.doOnReceive(DAGScheduler.scala:2297)
	at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.onReceive(DAGScheduler.scala:2246)
	at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.onReceive(DAGScheduler.scala:2235)
	at org.apache.spark.util.EventLoop$$anon$1.run(EventLoop.scala:49)
	at org.apache.spark.scheduler.DAGScheduler.runJob(DAGScheduler.scala:823)
	at org.apache.spark.SparkContext.runJob(SparkContext.scala:2108)
	at org.apache.spark.SparkContext.runJob(SparkContext.scala:2129)
	at org.apache.spark.SparkContext.runJob(SparkContext.scala:2148)
	at org.apache.spark.sql.execution.SparkPlan.executeTake(SparkPlan.scala:467)
	at org.apache.spark.sql.execution.SparkPlan.executeTake(SparkPlan.scala:420)
	at org.apache.spark.sql.execution.CollectLimitExec.executeCollect(limit.scala:47)
	at org.apache.spark.sql.Dataset.collectFromPlan(Dataset.scala:3653)
	at org.apache.spark.sql.Dataset.$anonfun$head$1(Dataset.scala:2695)
	at org.apache.spark.sql.Dataset.$anonfun$withAction$1(Dataset.scala:3644)
	at org.apache.spark.sql.execution.SQLExecution$.$anonfun$withNewExecutionId$5(SQLExecution.scala:103)
	at org.apache.spark.sql.execution.SQLExecution$.withSQLConfPropagated(SQLExecution.scala:163)
	at org.apache.spark.sql.execution.SQLExecution$.$anonfun$withNewExecutionId$1(SQLExecution.scala:90)
	at org.apache.spark.sql.SparkSession.withActive(SparkSession.scala:763)
	at org.apache.spark.sql.execution.SQLExecution$.withNewExecutionId(SQLExecution.scala:64)
	at org.apache.spark.sql.Dataset.withAction(Dataset.scala:3642)
	at org.apache.spark.sql.Dataset.head(Dataset.scala:2695)
	at org.apache.spark.sql.Dataset.take(Dataset.scala:2902)
	at org.apache.spark.sql.Dataset.getRows(Dataset.scala:300)
	at org.apache.spark.sql.Dataset.showString(Dataset.scala:337)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
	at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
	at py4j.Gateway.invoke(Gateway.java:282)
	at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
	at py4j.commands.CallCommand.execute(CallCommand.java:79)
	at py4j.GatewayConnection.run(GatewayConnection.java:238)
	at java.lang.Thread.run(Thread.java:748)
Caused by: org.apache.spark.api.python.PythonException: Traceback (most recent call last):
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 605, in main
    process()
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 597, in process
    serializer.dump_stream(out_iter, outfile)
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 223, in dump_stream
    self.serializer.dump_stream(self._batched(iterator), stream)
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 141, in dump_stream
    for obj in iterator:
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 212, in _batched
    for item in iterator:
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 450, in mapper
    result = tuple(f(*[a[o] for o in arg_offsets]) for (arg_offsets, f) in udfs)
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 450, in <genexpr>
    result = tuple(f(*[a[o] for o in arg_offsets]) for (arg_offsets, f) in udfs)
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 90, in <lambda>
    return lambda *a: f(*a)
  File "/.../spark/python/lib/pyspark.zip/pyspark/util.py", line 107, in wrapper
    return f(*args, **kwargs)
  File "<stdin>", line 3, in divide_by_zero
ZeroDivisionError: division by zero

	at org.apache.spark.api.python.BasePythonRunner$ReaderIterator.handlePythonException(PythonRunner.scala:516)
	at org.apache.spark.sql.execution.python.PythonUDFRunner$$anon$2.read(PythonUDFRunner.scala:81)
	at org.apache.spark.sql.execution.python.PythonUDFRunner$$anon$2.read(PythonUDFRunner.scala:64)
	at org.apache.spark.api.python.BasePythonRunner$ReaderIterator.hasNext(PythonRunner.scala:469)
	at org.apache.spark.InterruptibleIterator.hasNext(InterruptibleIterator.scala:37)
	at scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:489)
	at scala.collection.Iterator$$anon$10.hasNext(Iterator.scala:458)
	at scala.collection.Iterator$$anon$10.hasNext(Iterator.scala:458)
	at org.apache.spark.sql.catalyst.expressions.GeneratedClass$GeneratedIteratorForCodegenStage2.processNext(Unknown Source)
	at org.apache.spark.sql.execution.BufferedRowIterator.hasNext(BufferedRowIterator.java:43)
	at org.apache.spark.sql.execution.WholeStageCodegenExec$$anon$1.hasNext(WholeStageCodegenExec.scala:753)
	at org.apache.spark.sql.execution.SparkPlan.$anonfun$getByteArrayRdd$1(SparkPlan.scala:340)
	at org.apache.spark.rdd.RDD.$anonfun$mapPartitionsInternal$2(RDD.scala:898)
	at org.apache.spark.rdd.RDD.$anonfun$mapPartitionsInternal$2$adapted(RDD.scala:898)
	at org.apache.spark.rdd.MapPartitionsRDD.compute(MapPartitionsRDD.scala:52)
	at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:373)
	at org.apache.spark.rdd.RDD.iterator(RDD.scala:337)
	at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:90)
	at org.apache.spark.scheduler.Task.run(Task.scala:127)
	at org.apache.spark.executor.Executor$TaskRunner.$anonfun$run$3(Executor.scala:469)
	at org.apache.spark.util.Utils$.tryWithSafeFinally(Utils.scala:1377)
	at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:472)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	... 1 more
```

</details>

<details>
<summary>Python exception message without this change</summary>

```
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/.../spark/python/pyspark/sql/dataframe.py", line 427, in show
    print(self._jdf.showString(n, 20, vertical))
  File "/.../spark/python/lib/py4j-0.10.9-src.zip/py4j/java_gateway.py", line 1305, in __call__
  File "/.../spark/python/pyspark/sql/utils.py", line 98, in deco
    return f(*a, **kw)
  File "/.../spark/python/lib/py4j-0.10.9-src.zip/py4j/protocol.py", line 328, in get_return_value
py4j.protocol.Py4JJavaError: An error occurred while calling o160.showString.
: org.apache.spark.SparkException: Job aborted due to stage failure: Task 10 in stage 5.0 failed 4 times, most recent failure: Lost task 10.3 in stage 5.0 (TID 37, 192.168.35.193, executor 3): org.apache.spark.api.python.PythonException: Traceback (most recent call last):
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 605, in main
    process()
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 597, in process
    serializer.dump_stream(out_iter, outfile)
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 223, in dump_stream
    self.serializer.dump_stream(self._batched(iterator), stream)
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 141, in dump_stream
    for obj in iterator:
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 212, in _batched
    for item in iterator:
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 450, in mapper
    result = tuple(f(*[a[o] for o in arg_offsets]) for (arg_offsets, f) in udfs)
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 450, in <genexpr>
    result = tuple(f(*[a[o] for o in arg_offsets]) for (arg_offsets, f) in udfs)
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 90, in <lambda>
    return lambda *a: f(*a)
  File "/.../spark/python/lib/pyspark.zip/pyspark/util.py", line 107, in wrapper
    return f(*args, **kwargs)
  File "<stdin>", line 3, in divide_by_zero
ZeroDivisionError: division by zero

	at org.apache.spark.api.python.BasePythonRunner$ReaderIterator.handlePythonException(PythonRunner.scala:516)
	at org.apache.spark.sql.execution.python.PythonUDFRunner$$anon$2.read(PythonUDFRunner.scala:81)
	at org.apache.spark.sql.execution.python.PythonUDFRunner$$anon$2.read(PythonUDFRunner.scala:64)
	at org.apache.spark.api.python.BasePythonRunner$ReaderIterator.hasNext(PythonRunner.scala:469)
	at org.apache.spark.InterruptibleIterator.hasNext(InterruptibleIterator.scala:37)
	at scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:489)
	at scala.collection.Iterator$$anon$10.hasNext(Iterator.scala:458)
	at scala.collection.Iterator$$anon$10.hasNext(Iterator.scala:458)
	at org.apache.spark.sql.catalyst.expressions.GeneratedClass$GeneratedIteratorForCodegenStage2.processNext(Unknown Source)
	at org.apache.spark.sql.execution.BufferedRowIterator.hasNext(BufferedRowIterator.java:43)
	at org.apache.spark.sql.execution.WholeStageCodegenExec$$anon$1.hasNext(WholeStageCodegenExec.scala:753)
	at org.apache.spark.sql.execution.SparkPlan.$anonfun$getByteArrayRdd$1(SparkPlan.scala:340)
	at org.apache.spark.rdd.RDD.$anonfun$mapPartitionsInternal$2(RDD.scala:898)
	at org.apache.spark.rdd.RDD.$anonfun$mapPartitionsInternal$2$adapted(RDD.scala:898)
	at org.apache.spark.rdd.MapPartitionsRDD.compute(MapPartitionsRDD.scala:52)
	at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:373)
	at org.apache.spark.rdd.RDD.iterator(RDD.scala:337)
	at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:90)
	at org.apache.spark.scheduler.Task.run(Task.scala:127)
	at org.apache.spark.executor.Executor$TaskRunner.$anonfun$run$3(Executor.scala:469)
	at org.apache.spark.util.Utils$.tryWithSafeFinally(Utils.scala:1377)
	at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:472)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)

Driver stacktrace:
	at org.apache.spark.scheduler.DAGScheduler.failJobAndIndependentStages(DAGScheduler.scala:2117)
	at org.apache.spark.scheduler.DAGScheduler.$anonfun$abortStage$2(DAGScheduler.scala:2066)
	at org.apache.spark.scheduler.DAGScheduler.$anonfun$abortStage$2$adapted(DAGScheduler.scala:2065)
	at scala.collection.mutable.ResizableArray.foreach(ResizableArray.scala:62)
	at scala.collection.mutable.ResizableArray.foreach$(ResizableArray.scala:55)
	at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:49)
	at org.apache.spark.scheduler.DAGScheduler.abortStage(DAGScheduler.scala:2065)
	at org.apache.spark.scheduler.DAGScheduler.$anonfun$handleTaskSetFailed$1(DAGScheduler.scala:1021)
	at org.apache.spark.scheduler.DAGScheduler.$anonfun$handleTaskSetFailed$1$adapted(DAGScheduler.scala:1021)
	at scala.Option.foreach(Option.scala:407)
	at org.apache.spark.scheduler.DAGScheduler.handleTaskSetFailed(DAGScheduler.scala:1021)
	at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.doOnReceive(DAGScheduler.scala:2297)
	at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.onReceive(DAGScheduler.scala:2246)
	at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.onReceive(DAGScheduler.scala:2235)
	at org.apache.spark.util.EventLoop$$anon$1.run(EventLoop.scala:49)
	at org.apache.spark.scheduler.DAGScheduler.runJob(DAGScheduler.scala:823)
	at org.apache.spark.SparkContext.runJob(SparkContext.scala:2108)
	at org.apache.spark.SparkContext.runJob(SparkContext.scala:2129)
	at org.apache.spark.SparkContext.runJob(SparkContext.scala:2148)
	at org.apache.spark.sql.execution.SparkPlan.executeTake(SparkPlan.scala:467)
	at org.apache.spark.sql.execution.SparkPlan.executeTake(SparkPlan.scala:420)
	at org.apache.spark.sql.execution.CollectLimitExec.executeCollect(limit.scala:47)
	at org.apache.spark.sql.Dataset.collectFromPlan(Dataset.scala:3653)
	at org.apache.spark.sql.Dataset.$anonfun$head$1(Dataset.scala:2695)
	at org.apache.spark.sql.Dataset.$anonfun$withAction$1(Dataset.scala:3644)
	at org.apache.spark.sql.execution.SQLExecution$.$anonfun$withNewExecutionId$5(SQLExecution.scala:103)
	at org.apache.spark.sql.execution.SQLExecution$.withSQLConfPropagated(SQLExecution.scala:163)
	at org.apache.spark.sql.execution.SQLExecution$.$anonfun$withNewExecutionId$1(SQLExecution.scala:90)
	at org.apache.spark.sql.SparkSession.withActive(SparkSession.scala:763)
	at org.apache.spark.sql.execution.SQLExecution$.withNewExecutionId(SQLExecution.scala:64)
	at org.apache.spark.sql.Dataset.withAction(Dataset.scala:3642)
	at org.apache.spark.sql.Dataset.head(Dataset.scala:2695)
	at org.apache.spark.sql.Dataset.take(Dataset.scala:2902)
	at org.apache.spark.sql.Dataset.getRows(Dataset.scala:300)
	at org.apache.spark.sql.Dataset.showString(Dataset.scala:337)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
	at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
	at py4j.Gateway.invoke(Gateway.java:282)
	at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
	at py4j.commands.CallCommand.execute(CallCommand.java:79)
	at py4j.GatewayConnection.run(GatewayConnection.java:238)
	at java.lang.Thread.run(Thread.java:748)
Caused by: org.apache.spark.api.python.PythonException: Traceback (most recent call last):
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 605, in main
    process()
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 597, in process
    serializer.dump_stream(out_iter, outfile)
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 223, in dump_stream
    self.serializer.dump_stream(self._batched(iterator), stream)
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 141, in dump_stream
    for obj in iterator:
  File "/.../spark/python/lib/pyspark.zip/pyspark/serializers.py", line 212, in _batched
    for item in iterator:
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 450, in mapper
    result = tuple(f(*[a[o] for o in arg_offsets]) for (arg_offsets, f) in udfs)
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 450, in <genexpr>
    result = tuple(f(*[a[o] for o in arg_offsets]) for (arg_offsets, f) in udfs)
  File "/.../spark/python/lib/pyspark.zip/pyspark/worker.py", line 90, in <lambda>
    return lambda *a: f(*a)
  File "/.../spark/python/lib/pyspark.zip/pyspark/util.py", line 107, in wrapper
    return f(*args, **kwargs)
  File "<stdin>", line 3, in divide_by_zero
ZeroDivisionError: division by zero

	at org.apache.spark.api.python.BasePythonRunner$ReaderIterator.handlePythonException(PythonRunner.scala:516)
	at org.apache.spark.sql.execution.python.PythonUDFRunner$$anon$2.read(PythonUDFRunner.scala:81)
	at org.apache.spark.sql.execution.python.PythonUDFRunner$$anon$2.read(PythonUDFRunner.scala:64)
	at org.apache.spark.api.python.BasePythonRunner$ReaderIterator.hasNext(PythonRunner.scala:469)
	at org.apache.spark.InterruptibleIterator.hasNext(InterruptibleIterator.scala:37)
	at scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:489)
	at scala.collection.Iterator$$anon$10.hasNext(Iterator.scala:458)
	at scala.collection.Iterator$$anon$10.hasNext(Iterator.scala:458)
	at org.apache.spark.sql.catalyst.expressions.GeneratedClass$GeneratedIteratorForCodegenStage2.processNext(Unknown Source)
	at org.apache.spark.sql.execution.BufferedRowIterator.hasNext(BufferedRowIterator.java:43)
	at org.apache.spark.sql.execution.WholeStageCodegenExec$$anon$1.hasNext(WholeStageCodegenExec.scala:753)
	at org.apache.spark.sql.execution.SparkPlan.$anonfun$getByteArrayRdd$1(SparkPlan.scala:340)
	at org.apache.spark.rdd.RDD.$anonfun$mapPartitionsInternal$2(RDD.scala:898)
	at org.apache.spark.rdd.RDD.$anonfun$mapPartitionsInternal$2$adapted(RDD.scala:898)
	at org.apache.spark.rdd.MapPartitionsRDD.compute(MapPartitionsRDD.scala:52)
	at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:373)
	at org.apache.spark.rdd.RDD.iterator(RDD.scala:337)
	at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:90)
	at org.apache.spark.scheduler.Task.run(Task.scala:127)
	at org.apache.spark.executor.Executor$TaskRunner.$anonfun$run$3(Executor.scala:469)
	at org.apache.spark.util.Utils$.tryWithSafeFinally(Utils.scala:1377)
	at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:472)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	... 1 more
```

</details>

<br/>

Another example with Python 3.7:

```python
sql("a")
```

<details>
<summary>Python exception message when <code>spark.sql.pyspark.jvmStacktrace.enabled</code> is off (default)</summary>

```
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/.../spark/python/pyspark/sql/session.py", line 646, in sql
    return DataFrame(self._jsparkSession.sql(sqlQuery), self._wrapped)
  File "/.../spark/python/lib/py4j-0.10.9-src.zip/py4j/java_gateway.py", line 1305, in __call__
  File "/.../spark/python/pyspark/sql/utils.py", line 131, in deco
    raise_from(converted)
  File "<string>", line 3, in raise_from
pyspark.sql.utils.ParseException:
mismatched input 'a' expecting {'(', 'ADD', 'ALTER', 'ANALYZE', 'CACHE', 'CLEAR', 'COMMENT', 'COMMIT', 'CREATE', 'DELETE', 'DESC', 'DESCRIBE', 'DFS', 'DROP', 'EXPLAIN', 'EXPORT', 'FROM', 'GRANT', 'IMPORT', 'INSERT', 'LIST', 'LOAD', 'LOCK', 'MAP', 'MERGE', 'MSCK', 'REDUCE', 'REFRESH', 'REPLACE', 'RESET', 'REVOKE', 'ROLLBACK', 'SELECT', 'SET', 'SHOW', 'START', 'TABLE', 'TRUNCATE', 'UNCACHE', 'UNLOCK', 'UPDATE', 'USE', 'VALUES', 'WITH'}(line 1, pos 0)

== SQL ==
a
^^^
```

</details>

<details>
<summary>Python exception message when <code>spark.sql.pyspark.jvmStacktrace.enabled</code> is on</summary>

```
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/.../spark/python/pyspark/sql/session.py", line 646, in sql
    return DataFrame(self._jsparkSession.sql(sqlQuery), self._wrapped)
  File "/.../spark/python/lib/py4j-0.10.9-src.zip/py4j/java_gateway.py", line 1305, in __call__
  File "/.../spark/python/pyspark/sql/utils.py", line 131, in deco
    raise_from(converted)
  File "<string>", line 3, in raise_from
pyspark.sql.utils.ParseException:
mismatched input 'a' expecting {'(', 'ADD', 'ALTER', 'ANALYZE', 'CACHE', 'CLEAR', 'COMMENT', 'COMMIT', 'CREATE', 'DELETE', 'DESC', 'DESCRIBE', 'DFS', 'DROP', 'EXPLAIN', 'EXPORT', 'FROM', 'GRANT', 'IMPORT', 'INSERT', 'LIST', 'LOAD', 'LOCK', 'MAP', 'MERGE', 'MSCK', 'REDUCE', 'REFRESH', 'REPLACE', 'RESET', 'REVOKE', 'ROLLBACK', 'SELECT', 'SET', 'SHOW', 'START', 'TABLE', 'TRUNCATE', 'UNCACHE', 'UNLOCK', 'UPDATE', 'USE', 'VALUES', 'WITH'}(line 1, pos 0)

== SQL ==
a
^^^

JVM stacktrace:
org.apache.spark.sql.catalyst.parser.ParseException:
mismatched input 'a' expecting {'(', 'ADD', 'ALTER', 'ANALYZE', 'CACHE', 'CLEAR', 'COMMENT', 'COMMIT', 'CREATE', 'DELETE', 'DESC', 'DESCRIBE', 'DFS', 'DROP', 'EXPLAIN', 'EXPORT', 'FROM', 'GRANT', 'IMPORT', 'INSERT', 'LIST', 'LOAD', 'LOCK', 'MAP', 'MERGE', 'MSCK', 'REDUCE', 'REFRESH', 'REPLACE', 'RESET', 'REVOKE', 'ROLLBACK', 'SELECT', 'SET', 'SHOW', 'START', 'TABLE', 'TRUNCATE', 'UNCACHE', 'UNLOCK', 'UPDATE', 'USE', 'VALUES', 'WITH'}(line 1, pos 0)

== SQL ==
a
^^^

	at org.apache.spark.sql.catalyst.parser.ParseException.withCommand(ParseDriver.scala:266)
	at org.apache.spark.sql.catalyst.parser.AbstractSqlParser.parse(ParseDriver.scala:133)
	at org.apache.spark.sql.execution.SparkSqlParser.parse(SparkSqlParser.scala:49)
	at org.apache.spark.sql.catalyst.parser.AbstractSqlParser.parsePlan(ParseDriver.scala:81)
	at org.apache.spark.sql.SparkSession.$anonfun$sql$2(SparkSession.scala:604)
	at org.apache.spark.sql.catalyst.QueryPlanningTracker.measurePhase(QueryPlanningTracker.scala:111)
	at org.apache.spark.sql.SparkSession.$anonfun$sql$1(SparkSession.scala:604)
	at org.apache.spark.sql.SparkSession.withActive(SparkSession.scala:763)
	at org.apache.spark.sql.SparkSession.sql(SparkSession.scala:601)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
	at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
	at py4j.Gateway.invoke(Gateway.java:282)
	at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
	at py4j.commands.CallCommand.execute(CallCommand.java:79)
	at py4j.GatewayConnection.run(GatewayConnection.java:238)
	at java.lang.Thread.run(Thread.java:748)
```

</details>

<details>
<summary>Python exception message without this change</summary>

```
Traceback (most recent call last):
  File "/.../spark/python/pyspark/sql/utils.py", line 98, in deco
    return f(*a, **kw)
  File "/.../spark/python/lib/py4j-0.10.9-src.zip/py4j/protocol.py", line 328, in get_return_value
py4j.protocol.Py4JJavaError: An error occurred while calling o26.sql.
: org.apache.spark.sql.catalyst.parser.ParseException:
mismatched input 'a' expecting {'(', 'ADD', 'ALTER', 'ANALYZE', 'CACHE', 'CLEAR', 'COMMENT', 'COMMIT', 'CREATE', 'DELETE', 'DESC', 'DESCRIBE', 'DFS', 'DROP', 'EXPLAIN', 'EXPORT', 'FROM', 'GRANT', 'IMPORT', 'INSERT', 'LIST', 'LOAD', 'LOCK', 'MAP', 'MERGE', 'MSCK', 'REDUCE', 'REFRESH', 'REPLACE', 'RESET', 'REVOKE', 'ROLLBACK', 'SELECT', 'SET', 'SHOW', 'START', 'TABLE', 'TRUNCATE', 'UNCACHE', 'UNLOCK', 'UPDATE', 'USE', 'VALUES', 'WITH'}(line 1, pos 0)

== SQL ==
a
^^^

	at org.apache.spark.sql.catalyst.parser.ParseException.withCommand(ParseDriver.scala:266)
	at org.apache.spark.sql.catalyst.parser.AbstractSqlParser.parse(ParseDriver.scala:133)
	at org.apache.spark.sql.execution.SparkSqlParser.parse(SparkSqlParser.scala:49)
	at org.apache.spark.sql.catalyst.parser.AbstractSqlParser.parsePlan(ParseDriver.scala:81)
	at org.apache.spark.sql.SparkSession.$anonfun$sql$2(SparkSession.scala:604)
	at org.apache.spark.sql.catalyst.QueryPlanningTracker.measurePhase(QueryPlanningTracker.scala:111)
	at org.apache.spark.sql.SparkSession.$anonfun$sql$1(SparkSession.scala:604)
	at org.apache.spark.sql.SparkSession.withActive(SparkSession.scala:763)
	at org.apache.spark.sql.SparkSession.sql(SparkSession.scala:601)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
	at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
	at py4j.Gateway.invoke(Gateway.java:282)
	at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
	at py4j.commands.CallCommand.execute(CallCommand.java:79)
	at py4j.GatewayConnection.run(GatewayConnection.java:238)
	at java.lang.Thread.run(Thread.java:748)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/.../spark/python/pyspark/sql/session.py", line 646, in sql
    return DataFrame(self._jsparkSession.sql(sqlQuery), self._wrapped)
  File "/.../spark/python/lib/py4j-0.10.9-src.zip/py4j/java_gateway.py", line 1305, in __call__
  File "/.../spark/python/pyspark/sql/utils.py", line 102, in deco
    raise converted
pyspark.sql.utils.ParseException:
mismatched input 'a' expecting {'(', 'ADD', 'ALTER', 'ANALYZE', 'CACHE', 'CLEAR', 'COMMENT', 'COMMIT', 'CREATE', 'DELETE', 'DESC', 'DESCRIBE', 'DFS', 'DROP', 'EXPLAIN', 'EXPORT', 'FROM', 'GRANT', 'IMPORT', 'INSERT', 'LIST', 'LOAD', 'LOCK', 'MAP', 'MERGE', 'MSCK', 'REDUCE', 'REFRESH', 'REPLACE', 'RESET', 'REVOKE', 'ROLLBACK', 'SELECT', 'SET', 'SHOW', 'START', 'TABLE', 'TRUNCATE', 'UNCACHE', 'UNLOCK', 'UPDATE', 'USE', 'VALUES', 'WITH'}(line 1, pos 0)

== SQL ==
a
^^^
```

</details>

### Why are the changes needed?

Currently, PySpark exceptions are very unfriendly to Python users with causing a bunch of JVM stacktrace. See "Python exception message without this change" above.

### Does this PR introduce _any_ user-facing change?

Yes, it will change the exception message. See the examples above.

### How was this patch tested?

Manually tested by

```bash
./bin/pyspark --conf spark.sql.pyspark.jvmStacktrace.enabled=true
```

and running the examples above.

Closes #28661 from HyukjinKwon/python-debug.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-06-01 09:45:21 +09:00
Bryan Cutler 8bbb666622 [SPARK-25351][PYTHON][TEST][FOLLOWUP] Fix test assertions to be consistent
### What changes were proposed in this pull request?
Followup to make assertions from recent test consistent with the rest of the module

### Why are the changes needed?

Better to use assertions from `unittest` and be consistent

### Does this PR introduce _any_ user-facing change?

No

### How was this patch tested?

Existing tests

Closes #28659 from BryanCutler/arrow-category-test-fix-SPARK-25351.

Authored-by: Bryan Cutler <cutlerb@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-05-28 10:27:15 +09:00
iRakson 2f92ea0df4 [SPARK-31763][PYSPARK] Add inputFiles method in PySpark DataFrame Class
### What changes were proposed in this pull request?
Adds `inputFiles()` method to PySpark `DataFrame`. Using this, PySpark users can list all files constituting a `DataFrame`.

**Before changes:**

```
>>> spark.read.load("examples/src/main/resources/people.json", format="json").inputFiles()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/***/***/spark/python/pyspark/sql/dataframe.py", line 1388, in __getattr__
    "'%s' object has no attribute '%s'" % (self.__class__.__name__, name))
AttributeError: 'DataFrame' object has no attribute 'inputFiles'
```

**After changes:**

```
>>> spark.read.load("examples/src/main/resources/people.json", format="json").inputFiles()
[u'file:///***/***/spark/examples/src/main/resources/people.json']
```

### Why are the changes needed?
This method is already supported for spark with scala and java.

### Does this PR introduce _any_ user-facing change?
Yes, Now users can list all files of a DataFrame using `inputFiles()`

### How was this patch tested?
UT added.

Closes #28652 from iRakson/SPARK-31763.

Authored-by: iRakson <raksonrakesh@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-05-28 09:52:08 +09:00
Jalpan Randeri 339b0ecadb [SPARK-25351][SQL][PYTHON] Handle Pandas category type when converting from Python with Arrow
Handle Pandas category type while converting from python with Arrow enabled. The category column will be converted to whatever type the category elements are as is the case with Arrow disabled.

### Does this PR introduce any user-facing change?
No

### How was this patch tested?
New unit tests were added for `createDataFrame` and scalar `pandas_udf`

Closes #26585 from jalpan-randeri/feature-pyarrow-dictionary-type.

Authored-by: Jalpan Randeri <randerij@amazon.com>
Signed-off-by: Bryan Cutler <cutlerb@gmail.com>
2020-05-27 17:27:29 -07:00
David Toneian acab558e55 [SPARK-31739][PYSPARK][DOCS][MINOR] Fix docstring syntax issues and misplaced space characters
This commit is published into the public domain.

### What changes were proposed in this pull request?
Some syntax issues in docstrings have been fixed.

### Why are the changes needed?
In some places, the documentation did not render as intended, e.g. parameter documentations were not formatted as such.

### Does this PR introduce any user-facing change?
Slight improvements in documentation.

### How was this patch tested?
Manual testing and `dev/lint-python` run. No new Sphinx warnings arise due to this change.

Closes #28559 from DavidToneian/SPARK-31739.

Authored-by: David Toneian <david@toneian.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-05-18 20:25:02 +09:00
Kent Yao b31ae7bb0b [SPARK-31615][SQL] Pretty string output for sql method of RuntimeReplaceable expressions
### What changes were proposed in this pull request?

The RuntimeReplaceable ones are runtime replaceable, thus, their original parameters are not going to be resolved to PrettyAttribute and remain debug style string if we directly implement their `sql` methods with their parameters' `sql` methods.

This PR is raised with suggestions by maropu and cloud-fan https://github.com/apache/spark/pull/28402/files#r417656589. In this PR, we re-implement the `sql` methods of  the RuntimeReplaceable ones with toPettySQL

### Why are the changes needed?

Consistency of schema output between RuntimeReplaceable expressions and normal ones.

For example, `date_format` vs `to_timestamp`, before this PR, they output differently

#### Before
```sql
select date_format(timestamp '2019-10-06', 'yyyy-MM-dd uuuu')
struct<date_format(TIMESTAMP '2019-10-06 00:00:00', yyyy-MM-dd uuuu):string>

select to_timestamp("2019-10-06S10:11:12.12345", "yyyy-MM-dd'S'HH:mm:ss.SSSSSS")
struct<to_timestamp('2019-10-06S10:11:12.12345', 'yyyy-MM-dd\'S\'HH:mm:ss.SSSSSS'):timestamp>
```
#### After

```sql
select date_format(timestamp '2019-10-06', 'yyyy-MM-dd uuuu')
struct<date_format(TIMESTAMP '2019-10-06 00:00:00', yyyy-MM-dd uuuu):string>

select to_timestamp("2019-10-06T10:11:12'12", "yyyy-MM-dd'T'HH:mm:ss''SSSS")

struct<to_timestamp(2019-10-06T10:11:12'12, yyyy-MM-dd'T'HH:mm:ss''SSSS):timestamp>

````

### Does this PR introduce _any_ user-facing change?

Yes, the schema output style changed for the runtime replaceable expressions as shown in the above example

### How was this patch tested?
regenerate all related tests

Closes #28420 from yaooqinn/SPARK-31615.

Authored-by: Kent Yao <yaooqinn@hotmail.com>
Signed-off-by: Takeshi Yamamuro <yamamuro@apache.org>
2020-05-07 14:40:26 +09:00
HyukjinKwon 5dd581c88a [SPARK-29664][PYTHON][SQL][FOLLOW-UP] Add deprecation warnings for getItem instead
### What changes were proposed in this pull request?

This PR proposes to use a different approach instead of breaking it per Micheal's rubric added at https://spark.apache.org/versioning-policy.html. It deprecates the behaviour for now. It will be gradually removed in the future releases.

After this change,

```python
import warnings
warnings.simplefilter("always")
from pyspark.sql.functions import *
df = spark.range(2)
map_col = create_map(lit(0), lit(100), lit(1), lit(200))
df.withColumn("mapped", map_col.getItem(col('id'))).show()
```

```
/.../python/pyspark/sql/column.py:311: DeprecationWarning: A column as 'key' in getItem is
deprecated as of Spark 3.0, and will not be supported in the future release. Use `column[key]`
or `column.key` syntax instead.
  DeprecationWarning)
...
```

```python
import warnings
warnings.simplefilter("always")
from pyspark.sql.functions import *
df = spark.range(2)
struct_col = struct(lit(0), lit(100), lit(1), lit(200))
df.withColumn("struct", struct_col.getField(lit("col1"))).show()
```

```
/.../spark/python/pyspark/sql/column.py:336: DeprecationWarning: A column as 'name'
in getField is deprecated as of Spark 3.0, and will not be supported in the future release. Use
`column[name]` or `column.name` syntax instead.
  DeprecationWarning)
```

### Why are the changes needed?

To prevent the radical behaviour change after the amended versioning policy.

### Does this PR introduce any user-facing change?

Yes, it will show the deprecated warning message.

### How was this patch tested?

Manually tested.

Closes #28327 from HyukjinKwon/SPARK-29664.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-04-27 14:49:22 +09:00
Takuya UESHIN 87be3641eb [SPARK-31441] Support duplicated column names for toPandas with arrow execution
### What changes were proposed in this pull request?

This PR is adding support duplicated column names for `toPandas` with Arrow execution.

### Why are the changes needed?

When we execute `toPandas()` with Arrow execution, it fails if the column names have duplicates.

```py
>>> spark.sql("select 1 v, 1 v").toPandas()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/path/to/lib/python3.7/site-packages/pyspark/sql/dataframe.py", line 2132, in toPandas
    pdf = table.to_pandas()
  File "pyarrow/array.pxi", line 441, in pyarrow.lib._PandasConvertible.to_pandas
  File "pyarrow/table.pxi", line 1367, in pyarrow.lib.Table._to_pandas
  File "/path/to/lib/python3.7/site-packages/pyarrow/pandas_compat.py", line 653, in table_to_blockmanager
    columns = _deserialize_column_index(table, all_columns, column_indexes)
  File "/path/to/lib/python3.7/site-packages/pyarrow/pandas_compat.py", line 704, in _deserialize_column_index
    columns = _flatten_single_level_multiindex(columns)
  File "/path/to/lib/python3.7/site-packages/pyarrow/pandas_compat.py", line 937, in _flatten_single_level_multiindex
    raise ValueError('Found non-unique column index')
ValueError: Found non-unique column index
```

### Does this PR introduce any user-facing change?

Yes, previously we will face an error above, but after this PR, we will see the result:

```py
>>> spark.sql("select 1 v, 1 v").toPandas()
   v  v
0  1  1
```

### How was this patch tested?

Added and modified related tests.

Closes #28210 from ueshin/issues/SPARK-31441/to_pandas.

Authored-by: Takuya UESHIN <ueshin@databricks.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-04-14 14:08:56 +09:00
Kent Yao 31b907748d [SPARK-31414][SQL][DOCS][FOLLOWUP] Update default datetime pattern for json/csv APIs documentations
### What changes were proposed in this pull request?

Update default datetime pattern from `yyyy-MM-dd'T'HH:mm:ss.SSSXXX ` to `yyyy-MM-dd'T'HH:mm:ss[.SSS][XXX] ` for JSON/CSV APIs documentations

### Why are the changes needed?

doc fix

### Does this PR introduce any user-facing change?

Yes, the documentation will change

### How was this patch tested?

Passing Jenkins

Closes #28204 from yaooqinn/SPARK-31414-F.

Authored-by: Kent Yao <yaooqinn@hotmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-04-14 10:25:37 +09:00
HyukjinKwon c279e6b091 [SPARK-30722][DOCS][FOLLOW-UP] Explicitly mention the same entire input/output length restriction of Series Iterator UDF
### What changes were proposed in this pull request?

This PR explicitly mention that the requirement of Iterator of Series to Iterator of Series and Iterator of Multiple Series to Iterator of Series (previously Scalar Iterator pandas UDF).

The actual limitation of this UDF is the same length of the _entire input and output_, instead of each series's length. Namely you can do something as below:

```python
from typing import Iterator, Tuple
import pandas as pd
from pyspark.sql.functions import pandas_udf

pandas_udf("long")
def func(
        iterator: Iterator[pd.Series]) -> Iterator[pd.Series]:
    return iter([pd.concat(iterator)])

spark.range(100).select(func("id")).show()
```

This characteristic allows you to prefetch the data from the iterator to speed up, compared to the regular Scalar to Scalar (previously Scalar pandas UDF).

### Why are the changes needed?

To document the correct restriction and characteristics of a feature.

### Does this PR introduce any user-facing change?

Yes in the documentation but only in unreleased branches.

### How was this patch tested?

Github Actions should test the documentation build

Closes #28160 from HyukjinKwon/SPARK-30722-followup.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-04-09 16:46:27 +09:00
HyukjinKwon 4fafdcd63b [SPARK-26412][PYTHON][FOLLOW-UP] Improve error messages in Scala iterator pandas UDF
### What changes were proposed in this pull request?

This PR proposes to improve the error message from Scalar iterator pandas UDF.

### Why are the changes needed?

To show the correct error messages.

### Does this PR introduce any user-facing change?

Yes, but only in unreleased branches.

```python
import pandas as pd
from pyspark.sql.functions import pandas_udf, PandasUDFType

pandas_udf('long', PandasUDFType.SCALAR_ITER)
def pandas_plus_one(iterator):
      for _ in iterator:
            yield pd.Series(1)

spark.range(10).repartition(1).select(pandas_plus_one("id")).show()
```
```python
import pandas as pd
from pyspark.sql.functions import pandas_udf, PandasUDFType

pandas_udf('long', PandasUDFType.SCALAR_ITER)
def pandas_plus_one(iterator):
      for _ in iterator:
            yield pd.Series(list(range(20)))

spark.range(10).repartition(1).select(pandas_plus_one("id")).show()
```

**Before:**

```
RuntimeError: The number of output rows of pandas iterator UDF should
be the same with input rows. The input rows number is 10 but the output
rows number is 1.
```
```
AssertionError: Pandas MAP_ITER UDF outputted more rows than input rows.
```

**After:**

```
RuntimeError: The length of output in Scalar iterator pandas UDF should be
the same with the input's; however, the length of output was 1 and the length
of input was 10.
```
```
AssertionError: Pandas SCALAR_ITER UDF outputted more rows than input rows.
```

### How was this patch tested?

Unittests were fixed accordingly.

Closes #28135 from HyukjinKwon/SPARK-26412-followup.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-04-09 13:14:41 +09:00
Liang-Chi Hsieh 1f02871489 [SPARK-30921][PYSPARK] Predicates on python udf should not be pushdown through Aggregate
### What changes were proposed in this pull request?

This patch proposed to skip predicates on PythonUDFs to be pushdown through Aggregate.

### Why are the changes needed?

The predicates on PythonUDFs cannot be pushdown through Aggregate. Pushed down predicates cannot be evaluate because PythonUDFs cannot be evaluated on Filter and cause error like:

```
Caused by: java.lang.UnsupportedOperationException: Cannot generate code for expression: mean(input[1, struct<bar:bigint>, true].bar)
        at org.apache.spark.sql.catalyst.expressions.Unevaluable.doGenCode(Expression.scala:304)
        at org.apache.spark.sql.catalyst.expressions.Unevaluable.doGenCode$(Expression.scala:303)
        at org.apache.spark.sql.catalyst.expressions.PythonUDF.doGenCode(PythonUDF.scala:52)
        at org.apache.spark.sql.catalyst.expressions.Expression.$anonfun$genCode$3(Expression.scala:146)
        at scala.Option.getOrElse(Option.scala:189)
        at org.apache.spark.sql.catalyst.expressions.Expression.genCode(Expression.scala:141)
        at org.apache.spark.sql.catalyst.expressions.CastBase.doGenCode(Cast.scala:821)
        at org.apache.spark.sql.catalyst.expressions.Expression.$anonfun$genCode$3(Expression.scala:146)
        at scala.Option.getOrElse(Option.scala:189)
```

### Does this PR introduce any user-facing change?

Yes. Previously the predicates on PythonUDFs will be pushdown through Aggregate can cause error. After this change, the query can work.

### How was this patch tested?

Unit test.

Closes #28089 from viirya/SPARK-30921.

Authored-by: Liang-Chi Hsieh <viirya@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-04-06 09:36:20 +09:00
Ben Ryves fa37856710 [SPARK-31306][DOCS] update rand() function documentation to indicate exclusive upper bound
### What changes were proposed in this pull request?
A small documentation change to clarify that the `rand()` function produces values in `[0.0, 1.0)`.

### Why are the changes needed?
`rand()` uses `Rand()` - which generates values in [0, 1) ([documented here](a1dbcd13a3/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/randomExpressions.scala (L71))). The existing documentation suggests that 1.0 is a possible value returned by rand (i.e for a distribution written as `X ~ U(a, b)`, x can be a or b, so `U[0.0, 1.0]` suggests the value returned could include 1.0).

### Does this PR introduce any user-facing change?
Only documentation changes.

### How was this patch tested?
Documentation changes only.

Closes #28071 from Smeb/master.

Authored-by: Ben Ryves <benjamin.ryves@getyourguide.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-03-31 15:16:17 +09:00
Maxim Gekk d2ff5c5bfb [SPARK-31286][SQL][DOC] Specify formats of time zone ID for JSON/CSV option and from/to_utc_timestamp
### What changes were proposed in this pull request?
In the PR, I propose to update the doc for the `timeZone` option in JSON/CSV datasources and for the `tz` parameter of the `from_utc_timestamp()`/`to_utc_timestamp()` functions, and to restrict format of config's values to 2 forms:
1. Geographical regions, such as `America/Los_Angeles`.
2. Fixed offsets - a fully resolved offset from UTC. For example, `-08:00`.

### Why are the changes needed?
Other formats such as three-letter time zone IDs are ambitious, and depend on the locale. For example, `CST` could be U.S. `Central Standard Time` and `China Standard Time`. Such formats have been already deprecated in JDK, see [Three-letter time zone IDs](https://docs.oracle.com/javase/8/docs/api/java/util/TimeZone.html).

### Does this PR introduce any user-facing change?
No

### How was this patch tested?
By running `./dev/scalastyle`, and manual testing.

Closes #28051 from MaxGekk/doc-time-zone-option.

Authored-by: Maxim Gekk <max.gekk@gmail.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2020-03-30 12:20:11 +08:00
gatorsmile 3884455780 [SPARK-31087] [SQL] Add Back Multiple Removed APIs
### What changes were proposed in this pull request?

Based on the discussion in the mailing list [[Proposal] Modification to Spark's Semantic Versioning Policy](http://apache-spark-developers-list.1001551.n3.nabble.com/Proposal-Modification-to-Spark-s-Semantic-Versioning-Policy-td28938.html) , this PR is to add back the following APIs whose maintenance cost are relatively small.

- functions.toDegrees/toRadians
- functions.approxCountDistinct
- functions.monotonicallyIncreasingId
- Column.!==
- Dataset.explode
- Dataset.registerTempTable
- SQLContext.getOrCreate, setActive, clearActive, constructors

Below is the other removed APIs in the original PR, but not added back in this PR [https://issues.apache.org/jira/browse/SPARK-25908]:

- Remove some AccumulableInfo .apply() methods
- Remove non-label-specific multiclass precision/recall/fScore in favor of accuracy
- Remove unused Python StorageLevel constants
- Remove unused multiclass option in libsvm parsing
- Remove references to deprecated spark configs like spark.yarn.am.port
- Remove TaskContext.isRunningLocally
- Remove ShuffleMetrics.shuffle* methods
- Remove BaseReadWrite.context in favor of session

### Why are the changes needed?
Avoid breaking the APIs that are commonly used.

### Does this PR introduce any user-facing change?
Adding back the APIs that were removed in 3.0 branch does not introduce the user-facing changes, because Spark 3.0 has not been released.

### How was this patch tested?
Added a new test suite for these APIs.

Author: gatorsmile <gatorsmile@gmail.com>
Author: yi.wu <yi.wu@databricks.com>

Closes #27821 from gatorsmile/addAPIBackV2.
2020-03-28 22:05:16 -07:00
HyukjinKwon 3165a95a04 [SPARK-31287][PYTHON][SQL] Ignore type hints in groupby.(cogroup.)applyInPandas and mapInPandas
### What changes were proposed in this pull request?

This PR proposes to make pandas function APIs (`groupby.(cogroup.)applyInPandas` and `mapInPandas`) to ignore Python type hints.

### Why are the changes needed?

Python type hints are optional. It shouldn't affect where pandas UDFs are not used.
This is also a future work for them to support other type hints. We shouldn't at least throw an exception at this moment.

### Does this PR introduce any user-facing change?

No, it's master-only change.

```python
import pandas as pd

def pandas_plus_one(pdf: pd.DataFrame) -> pd.DataFrame:
    return pdf + 1

spark.range(10).groupby('id').applyInPandas(pandas_plus_one, schema="id long").show()
```
```python
import pandas as pd

def pandas_plus_one(left: pd.DataFrame, right: pd.DataFrame) -> pd.DataFrame:
    return left + 1

spark.range(10).groupby('id').cogroup(spark.range(10).groupby("id")).applyInPandas(pandas_plus_one, schema="id long").show()
```

```python
from typing import Iterator
import pandas as pd

def pandas_plus_one(iter: Iterator[pd.DataFrame]) -> Iterator[pd.DataFrame]:
    return map(lambda v: v + 1, iter)

spark.range(10).mapInPandas(pandas_plus_one, schema="id long").show()
```

**Before:**

Exception

**After:**

```
+---+
| id|
+---+
|  1|
|  2|
|  3|
|  4|
|  5|
|  6|
|  7|
|  8|
|  9|
| 10|
+---+
```

### How was this patch tested?

Closes #28052 from HyukjinKwon/SPARK-31287.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-03-29 13:59:18 +09:00
gatorsmile b9eafcb526 [SPARK-31088][SQL] Add back HiveContext and createExternalTable
### What changes were proposed in this pull request?
Based on the discussion in the mailing list [[Proposal] Modification to Spark's Semantic Versioning Policy](http://apache-spark-developers-list.1001551.n3.nabble.com/Proposal-Modification-to-Spark-s-Semantic-Versioning-Policy-td28938.html) , this PR is to add back the following APIs whose maintenance cost are relatively small.

- HiveContext
- createExternalTable APIs

### Why are the changes needed?

Avoid breaking the APIs that are commonly used.

### Does this PR introduce any user-facing change?
Adding back the APIs that were removed in 3.0 branch does not introduce the user-facing changes, because Spark 3.0 has not been released.

### How was this patch tested?

add a new test suite for createExternalTable APIs.

Closes #27815 from gatorsmile/addAPIsBack.

Lead-authored-by: gatorsmile <gatorsmile@gmail.com>
Co-authored-by: yi.wu <yi.wu@databricks.com>
Signed-off-by: gatorsmile <gatorsmile@gmail.com>
2020-03-26 23:51:15 -07:00
Liang-Chi Hsieh 559d3e4051 [SPARK-31186][PYSPARK][SQL] toPandas should not fail on duplicate column names
### What changes were proposed in this pull request?

When `toPandas` API works on duplicate column names produced from operators like join, we see the error like:

```
ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().
```

This patch fixes the error in `toPandas` API.

### Why are the changes needed?

To make `toPandas` work on dataframe with duplicate column names.

### Does this PR introduce any user-facing change?

Yes. Previously calling `toPandas` API on a dataframe with duplicate column names will fail. After this patch, it will produce correct result.

### How was this patch tested?

Unit test.

Closes #28025 from viirya/SPARK-31186.

Authored-by: Liang-Chi Hsieh <viirya@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-03-27 12:10:30 +09:00
Kent Yao b024a8a69e [MINOR][DOCS] Fix some links for python api doc
### What changes were proposed in this pull request?

the link for `partition discovery` is malformed, because for releases, there will contains` /docs/<version>/` in the full URL.

### Why are the changes needed?

fix doc

### Does this PR introduce any user-facing change?

no

### How was this patch tested?

`SKIP_SCALADOC=1 SKIP_RDOC=1 SKIP_SQLDOC=1 jekyll serve` locally verified

Closes #28017 from yaooqinn/doc.

Authored-by: Kent Yao <yaooqinn@hotmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-03-26 13:06:21 +09:00
Kent Yao 88ae6c4481 [SPARK-31189][SQL][DOCS] Fix errors and missing parts for datetime pattern document
### What changes were proposed in this pull request?

Fix errors and missing parts for datetime pattern document
1. The pattern we use is similar to DateTimeFormatter and SimpleDateFormat but not identical. So we shouldn't use any of them in the API docs but use a link to the doc of our own.
2. Some pattern letters are missing
3. Some pattern letters are explicitly banned - Set('A', 'c', 'e', 'n', 'N')
4. the second fraction pattern different logic for parsing and formatting

### Why are the changes needed?

fix and improve doc
### Does this PR introduce any user-facing change?

yes, new and updated doc
### How was this patch tested?

pass Jenkins
viewed locally with `jekyll serve`
![image](https://user-images.githubusercontent.com/8326978/77044447-6bd3bb00-69fa-11ea-8d6f-7084166c5dea.png)

Closes #27956 from yaooqinn/SPARK-31189.

Authored-by: Kent Yao <yaooqinn@hotmail.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2020-03-20 21:59:26 +08:00
zero323 01f20394ac [SPARK-30569][SQL][PYSPARK][SPARKR] Add percentile_approx DSL functions
### What changes were proposed in this pull request?

- Adds following overloaded variants to Scala `o.a.s.sql.functions`:

  - `percentile_approx(e: Column, percentage: Array[Double], accuracy: Long): Column`
  - `percentile_approx(columnName: String, percentage: Array[Double], accuracy: Long): Column`
  - `percentile_approx(e: Column, percentage: Double, accuracy: Long): Column`
  - `percentile_approx(columnName: String, percentage: Double, accuracy: Long): Column`
  - `percentile_approx(e: Column, percentage: Seq[Double], accuracy: Long): Column` (primarily for
Python interop).
  - `percentile_approx(columnName: String, percentage: Seq[Double], accuracy: Long): Column`

- Adds `percentile_approx` to `pyspark.sql.functions`.

- Adds `percentile_approx` function to SparkR.

### Why are the changes needed?

Currently we support `percentile_approx` only in SQL expression. It is inconvenient and makes this function relatively unknown.

### Does this PR introduce any user-facing change?

No.

### How was this patch tested?

New unit tests for SparkR an PySpark.

As for now there are no additional tests in Scala API ‒ `ApproximatePercentile` is well tested and Python (including docstrings) and R tests provide additional tests, so it seems unnecessary.

Closes #27278 from zero323/SPARK-30569.

Lead-authored-by: zero323 <mszymkiewicz@gmail.com>
Co-authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-03-17 10:44:21 +09:00
Yuanjian Li 3493162c78 [SPARK-31030][SQL] Backward Compatibility for Parsing and formatting Datetime
### What changes were proposed in this pull request?
In Spark version 2.4 and earlier, datetime parsing, formatting and conversion are performed by using the hybrid calendar (Julian + Gregorian).
Since the Proleptic Gregorian calendar is de-facto calendar worldwide, as well as the chosen one in ANSI SQL standard, Spark 3.0 switches to it by using Java 8 API classes (the java.time packages that are based on ISO chronology ). The switching job is completed in SPARK-26651.
But after the switching, there are some patterns not compatible between Java 8 and Java 7, Spark needs its own definition on the patterns rather than depends on Java API.
In this PR, we achieve this by writing the document and shadow the incompatible letters. See more details in [SPARK-31030](https://issues.apache.org/jira/browse/SPARK-31030)

### Why are the changes needed?
For backward compatibility.

### Does this PR introduce any user-facing change?
No.
After we define our own datetime parsing and formatting patterns, it's same to old Spark version.

### How was this patch tested?
Existing and new added UT.
Locally document test:
![image](https://user-images.githubusercontent.com/4833765/76064100-f6acc280-5fc3-11ea-9ef7-82e7dc074205.png)

Closes #27830 from xuanyuanking/SPARK-31030.

Authored-by: Yuanjian Li <xyliyuanjian@gmail.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2020-03-11 14:11:13 +08:00
Liang-Chi Hsieh d21aab403a
[SPARK-30941][PYSPARK] Add a note to asDict to document its behavior when there are duplicate fields
### What changes were proposed in this pull request?

Adding a note to document `Row.asDict` behavior when there are duplicate fields.

### Why are the changes needed?

When a row contains duplicate fields, `asDict` and `_get_item_` behaves differently. We should document it to let users know the difference explicitly.

### Does this PR introduce any user-facing change?

No. Only document change.

### How was this patch tested?

Existing test.

Closes #27853 from viirya/SPARK-30941.

Authored-by: Liang-Chi Hsieh <viirya@gmail.com>
Signed-off-by: Dongjoon Hyun <dongjoon@apache.org>
2020-03-09 11:06:45 -07:00
zero323 7de33f56e8 [SPARK-30681][PYSPARK][SQL] Add higher order functions API to PySpark
### What changes were proposed in this pull request?

This PR add Python API for invoking following higher functions:

- `transform`
- `exists`
- `forall`
- `filter`
- `aggregate`
- `zip_with`
- `transform_keys`
- `transform_values`
- `map_filter`
- `map_zip_with`

to `pyspark.sql`. Each of these accepts plain Python functions of one of the following types

- `(Column) -> Column: ...`
- `(Column, Column) -> Column: ...`
- `(Column, Column, Column) -> Column: ...`

Internally this proposal piggbacks on objects supporting Scala implementation ([SPARK-27297](https://issues.apache.org/jira/browse/SPARK-27297)) by:

1. Creating  required `UnresolvedNamedLambdaVariables`  exposing these as PySpark `Columns`
2. Invoking Python function with these columns as arguments.
3. Using the result, and underlying JVM objects from 1., to create `expressions.LambdaFunction` which is passed to desired expression, and repacked as Python `Column`.

### Why are the changes needed?

Currently higher order functions are available only using SQL and Scala API and can use only SQL expressions

```python
df.selectExpr("transform(values, x -> x + 1)")
```

This works reasonably well for simple functions, but can get really ugly with complex functions (complex functions, casts), resulting objects are somewhat verbose and we don't get any IDE support.  Additionally DSL used, though  very simple, is not documented.

With changes propose here, above query could be rewritten as:

```python
df.select(transform("values", lambda x: x + 1))
```

### Does this PR introduce any user-facing change?

No.

### How was this patch tested?

- For positive cases this PR adds doctest strings covering possible usage patterns.
- For negative cases (unsupported function types) this PR adds unit tests.

### Notes

If approved, the same approach can be used in SparkR.

Closes #27406 from zero323/SPARK-30681.

Authored-by: zero323 <mszymkiewicz@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-02-28 12:59:39 +09:00
Eric Wu 1f0300fb16 [SPARK-30764][SQL] Improve the readability of EXPLAIN FORMATTED style
### What changes were proposed in this pull request?
The style of `EXPLAIN FORMATTED` output needs to be improved. We’ve already got some observations/ideas in
https://github.com/apache/spark/pull/27368#discussion_r376694496
https://github.com/apache/spark/pull/27368#discussion_r376927143

Observations/Ideas:
1. Using comma as the separator is not clear, especially commas are used inside the expressions too.
2. Show the column counts first? For example, `Results [4]: …`
3. Currently the attribute names are automatically generated, this need to refined.
4. Add arguments field in common implementations as `EXPLAIN EXTENDED` did by calling `argString` in `TreeNode.simpleString`. This will eliminate most existing minor differences between
`EXPLAIN EXTENDED` and `EXPLAIN FORMATTED`.
5. Another improvement we can do is: the generated alias shouldn't include attribute id. collect_set(val, 0, 0)#123 looks clearer than collect_set(val#456, 0, 0)#123

This PR is currently addressing comments 2 & 4, and open for more discussions on improving readability.

### Why are the changes needed?
The readability of `EXPLAIN FORMATTED` need to be improved, which will help user better understand the query plan.

### Does this PR introduce any user-facing change?
Yes, `EXPLAIN FORMATTED` output style changed.

### How was this patch tested?
Update expect results of test cases in explain.sql

Closes #27509 from Eric5553/ExplainFormattedRefine.

Authored-by: Eric Wu <492960551@qq.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2020-02-21 23:36:14 +08:00