6a5a7254dc
## What changes were proposed in this pull request?
`input_file_name` doesn't return filename when working with UDF in PySpark. An example shows the problem:
from pyspark.sql.functions import *
from pyspark.sql.types import *
def filename(path):
return path
sourceFile = udf(filename, StringType())
spark.read.json("tmp.json").select(sourceFile(input_file_name())).show()
+---------------------------+
|filename(input_file_name())|
+---------------------------+
| |
+---------------------------+
The cause of this issue is, we group rows in `BatchEvalPythonExec` for batching processing of PythonUDF. Currently we group rows first and then evaluate expressions on the rows. If the data is less than the required number of rows for a group, the iterator will be consumed to the end before the evaluation. However, once the iterator reaches the end, we will unset input filename. So the input_file_name expression can't return correct filename.
This patch fixes the approach to group the batch of rows. We evaluate the expression first and then group evaluated results to batch.
## How was this patch tested?
Added unit test to PySpark.
Please review http://spark.apache.org/contributing.html before opening a pull request.
Author: Liang-Chi Hsieh <viirya@gmail.com>
Closes #16115 from viirya/fix-py-udf-input-filename.
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| catalyst | ||
| core | ||
| hive | ||
| hive-thriftserver | ||
| README.md | ||
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 an extension of SQLContext called HiveContext that allows users to write queries using a subset of HiveQL and access data from a Hive Metastore using Hive SerDes. There are also wrappers that allows 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.