spark-instrumented-optimizer/python
Hyukjin Kwon fee87f13d1 [SPARK-36338][PYTHON][SQL] Move distributed-sequence implementation to Scala side
### What changes were proposed in this pull request?

This PR proposes to implement `distributed-sequence` index in Scala side.

### Why are the changes needed?

- Avoid unnecessary (de)serialization
- Keep the nullability in the input DataFrame when `distributed-sequence` is enabled. During the serialization, all fields are being nullable for now (see https://github.com/apache/spark/pull/32775#discussion_r645882104)

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

No to end users since pandas API on Spark is not released yet.

```python
import pyspark.pandas as ps
ps.set_option('compute.default_index_type', 'distributed-sequence')
ps.range(1).spark.print_schema()
```

Before:

```
root
 |-- id: long (nullable = true)
```

After:

```
root
 |-- id: long (nullable = false)
```

### How was this patch tested?

Manually tested, and existing tests should cover them.

Closes #33570 from HyukjinKwon/SPARK-36338.

Authored-by: Hyukjin Kwon <gurwls223@apache.org>
Signed-off-by: Hyukjin Kwon <gurwls223@apache.org>
(cherry picked from commit c6140d4d0a)
Signed-off-by: Hyukjin Kwon <gurwls223@apache.org>
2021-07-30 22:29:31 +09:00
..
docs [SPARK-36288][DOCS][PYTHON] Update API usage on pyspark pandas documents 2021-07-27 12:31:00 +09:00
lib [SPARK-34688][PYTHON] Upgrade to Py4J 0.10.9.2 2021-03-11 09:51:41 -06:00
pyspark [SPARK-36338][PYTHON][SQL] Move distributed-sequence implementation to Scala side 2021-07-30 22:29:31 +09:00
test_coverage [SPARK-7721][PYTHON][TESTS] Adds PySpark coverage generation script 2018-01-22 22:12:50 +09:00
test_support Spelling r common dev mlib external project streaming resource managers python 2020-11-27 10:22:45 -06:00
.coveragerc [SPARK-7721][PYTHON][TESTS] Adds PySpark coverage generation script 2018-01-22 22:12:50 +09:00
.gitignore [SPARK-3946] gitignore in /python includes wrong directory 2014-10-14 14:09:39 -07:00
MANIFEST.in [SPARK-32714][PYTHON] Initial pyspark-stubs port 2020-09-24 14:15:36 +09:00
mypy.ini [SPARK-35684][INFRA][PYTHON] Bump up mypy version in GitHub Actions 2021-07-07 13:26:41 +09:00
pylintrc [SPARK-32435][PYTHON] Remove heapq3 port from Python 3 2020-07-27 20:10:13 +09:00
README.md [SPARK-30884][PYSPARK] Upgrade to Py4J 0.10.9 2020-02-20 09:09:30 -08:00
run-tests [SPARK-29672][PYSPARK] update spark testing framework to use python3 2019-11-14 10:18:55 -08:00
run-tests-with-coverage [SPARK-34968][TEST][PYTHON] Add the -fr argument to xargs rm 2021-04-06 15:20:55 -07:00
run-tests.py [SPARK-32194][PYTHON] Use proper exception classes instead of plain Exception 2021-05-26 11:54:40 +09:00
setup.cfg [SPARK-1267][SPARK-18129] Allow PySpark to be pip installed 2016-11-16 14:22:15 -08:00
setup.py [SPARK-35759][PYTHON] Remove the upperbound for numpy for pandas-on-Spark 2021-06-15 09:59:05 +09:00

Apache Spark

Spark is a unified analytics engine for large-scale data processing. It provides high-level APIs in Scala, Java, Python, and R, and an optimized engine that supports general computation graphs for data analysis. It also supports a rich set of higher-level tools including Spark SQL for SQL and DataFrames, MLlib for machine learning, GraphX for graph processing, and Structured Streaming for stream processing.

https://spark.apache.org/

Online Documentation

You can find the latest Spark documentation, including a programming guide, on the project web page

Python Packaging

This README file only contains basic information related to pip installed PySpark. This packaging is currently experimental and may change in future versions (although we will do our best to keep compatibility). Using PySpark requires the Spark JARs, and if you are building this from source please see the builder instructions at "Building Spark".

The Python packaging for Spark is not intended to replace all of the other use cases. This Python packaged version of Spark is suitable for interacting with an existing cluster (be it Spark standalone, YARN, or Mesos) - but does not contain the tools required to set up your own standalone Spark cluster. You can download the full version of Spark from the Apache Spark downloads page.

NOTE: If you are using this with a Spark standalone cluster you must ensure that the version (including minor version) matches or you may experience odd errors.

Python Requirements

At its core PySpark depends on Py4J, but some additional sub-packages have their own extra requirements for some features (including numpy, pandas, and pyarrow).