spark-instrumented-optimizer/sql
HyukjinKwon e2c7bfce40 [SPARK-33407][PYTHON] Simplify the exception message from Python UDFs (disabled by default)
### What changes were proposed in this pull request?

This PR proposes to simplify the exception messages from Python UDFS.

Currently, the exception message from Python UDFs is as below:

```python
from pyspark.sql.functions import udf; spark.range(10).select(udf(lambda x: x/0)("id")).collect()
```

```python
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/.../python/pyspark/sql/dataframe.py", line 427, in show
    print(self._jdf.showString(n, 20, vertical))
  File "/.../python/lib/py4j-0.10.9-src.zip/py4j/java_gateway.py", line 1305, in __call__
  File "/.../python/pyspark/sql/utils.py", line 127, 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:
Traceback (most recent call last):
  File "/.../python/lib/pyspark.zip/pyspark/worker.py", line 605, in main
    process()
  File "/.../python/lib/pyspark.zip/pyspark/worker.py", line 597, in process
    serializer.dump_stream(out_iter, outfile)
  File "/.../python/lib/pyspark.zip/pyspark/serializers.py", line 223, in dump_stream
    self.serializer.dump_stream(self._batched(iterator), stream)
  File "/.../python/lib/pyspark.zip/pyspark/serializers.py", line 141, in dump_stream
    for obj in iterator:
  File "/.../python/lib/pyspark.zip/pyspark/serializers.py", line 212, in _batched
    for item in iterator:
  File "/.../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 "/.../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 "/.../python/lib/pyspark.zip/pyspark/worker.py", line 90, in <lambda>
    return lambda *a: f(*a)
  File "/.../python/lib/pyspark.zip/pyspark/util.py", line 107, in wrapper
    return f(*args, **kwargs)
  File "<stdin>", line 1, in <lambda>
ZeroDivisionError: division by zero
```

Actually, almost all cases, users only care about `ZeroDivisionError: division by zero`. We don't really have to show the internal stuff in 99% cases.

This PR adds a configuration `spark.sql.execution.pyspark.udf.simplifiedException.enabled` (disabled by default) that hides the internal tracebacks related to Python worker, (de)serialization, etc.

```python
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/.../python/pyspark/sql/dataframe.py", line 427, in show
    print(self._jdf.showString(n, 20, vertical))
  File "/.../python/lib/py4j-0.10.9-src.zip/py4j/java_gateway.py", line 1305, in __call__
  File "/.../python/pyspark/sql/utils.py", line 127, 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:
Traceback (most recent call last):
  File "<stdin>", line 1, in <lambda>
ZeroDivisionError: division by zero
```

The trackback will be shown from the point when any non-PySpark file is seen in the traceback.

### Why are the changes needed?

Without this configuration. such internal tracebacks are exposed to users directly especially for shall or notebook users in PySpark. 99% cases people don't care about the internal Python worker, (de)serialization and related tracebacks. It just makes the exception more difficult to read. For example, one statement of `x/0` above shows a very long traceback and most of them are unnecessary.

This configuration enables the ability to show simplified tracebacks which users will likely be most interested in.

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

By default, no. It adds one configuration that simplifies the exception message. See the example above.

### How was this patch tested?

Manually tested:

```bash
$ pyspark --conf spark.sql.execution.pyspark.udf.simplifiedException.enabled=true
```
```python
from pyspark.sql.functions import udf; spark.sparkContext.setLogLevel("FATAL"); spark.range(10).select(udf(lambda x: x/0)("id")).collect()
```

and unittests were also added.

Closes #30309 from HyukjinKwon/SPARK-33407.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-11-17 14:15:31 +09:00
..
catalyst [SPARK-33407][PYTHON] Simplify the exception message from Python UDFs (disabled by default) 2020-11-17 14:15:31 +09:00
core [SPARK-33407][PYTHON] Simplify the exception message from Python UDFs (disabled by default) 2020-11-17 14:15:31 +09:00
hive [SPARK-33453][SQL][TESTS] Unify v1 and v2 SHOW PARTITIONS tests 2020-11-16 16:11:42 +00:00
hive-thriftserver [SPARK-33358][SQL] Return code when command process failed 2020-11-15 16:57:12 -08:00
create-docs.sh [SPARK-31550][SQL][DOCS] Set nondeterministic configurations with general meanings in sql configuration doc 2020-04-27 17:08:52 +09:00
gen-sql-api-docs.py [SPARK-31474][SQL][FOLLOWUP] Replace _FUNC_ placeholder with functionname in the note field of expression info 2020-04-23 13:33:04 +09:00
gen-sql-config-docs.py [SPARK-31550][SQL][DOCS] Set nondeterministic configurations with general meanings in sql configuration doc 2020-04-27 17:08:52 +09:00
gen-sql-functions-docs.py [SPARK-31562][SQL] Update ExpressionDescription for substring, current_date, and current_timestamp 2020-04-26 11:46:52 -07:00
mkdocs.yml [SPARK-30731] Update deprecated Mkdocs option 2020-02-19 17:28:58 +09:00
README.md [SPARK-30510][SQL][DOCS] Publicly document Spark SQL configuration options 2020-02-09 19:20:47 +09:00

Spark SQL

This module provides support for executing relational queries expressed in either SQL or the DataFrame/Dataset API.

Spark SQL is broken up into four subprojects:

  • Catalyst (sql/catalyst) - An implementation-agnostic framework for manipulating trees of relational operators and expressions.
  • Execution (sql/core) - A query planner / execution engine for translating Catalyst's logical query plans into Spark RDDs. This component also includes a new public interface, SQLContext, that allows users to execute SQL or LINQ statements against existing RDDs and Parquet files.
  • Hive Support (sql/hive) - Includes extensions that allow users to write queries using a subset of HiveQL and access data from a Hive Metastore using Hive SerDes. There are also wrappers that allow users to run queries that include Hive UDFs, UDAFs, and UDTFs.
  • HiveServer and CLI support (sql/hive-thriftserver) - Includes support for the SQL CLI (bin/spark-sql) and a HiveServer2 (for JDBC/ODBC) compatible server.

Running ./sql/create-docs.sh generates SQL documentation for built-in functions under sql/site, and SQL configuration documentation that gets included as part of configuration.md in the main docs directory.