spark-instrumented-optimizer/python
mn-mikke e6b466084c [SPARK-23736][SQL] Extending the concat function to support array columns
## What changes were proposed in this pull request?
The PR adds a logic for easy concatenation of multiple array columns and covers:
- Concat expression has been extended to support array columns
- A Python wrapper

## How was this patch tested?
New tests added into:
- CollectionExpressionsSuite
- DataFrameFunctionsSuite
- typeCoercion/native/concat.sql

## Codegen examples
### Primitive-type elements
```
val df = Seq(
  (Seq(1 ,2), Seq(3, 4)),
  (Seq(1, 2, 3), null)
).toDF("a", "b")
df.filter('a.isNotNull).select(concat('a, 'b)).debugCodegen()
```
Result:
```
/* 033 */         boolean inputadapter_isNull = inputadapter_row.isNullAt(0);
/* 034 */         ArrayData inputadapter_value = inputadapter_isNull ?
/* 035 */         null : (inputadapter_row.getArray(0));
/* 036 */
/* 037 */         if (!(!inputadapter_isNull)) continue;
/* 038 */
/* 039 */         ((org.apache.spark.sql.execution.metric.SQLMetric) references[0] /* numOutputRows */).add(1);
/* 040 */
/* 041 */         ArrayData[] project_args = new ArrayData[2];
/* 042 */
/* 043 */         if (!false) {
/* 044 */           project_args[0] = inputadapter_value;
/* 045 */         }
/* 046 */
/* 047 */         boolean inputadapter_isNull1 = inputadapter_row.isNullAt(1);
/* 048 */         ArrayData inputadapter_value1 = inputadapter_isNull1 ?
/* 049 */         null : (inputadapter_row.getArray(1));
/* 050 */         if (!inputadapter_isNull1) {
/* 051 */           project_args[1] = inputadapter_value1;
/* 052 */         }
/* 053 */
/* 054 */         ArrayData project_value = new Object() {
/* 055 */           public ArrayData concat(ArrayData[] args) {
/* 056 */             for (int z = 0; z < 2; z++) {
/* 057 */               if (args[z] == null) return null;
/* 058 */             }
/* 059 */
/* 060 */             long project_numElements = 0L;
/* 061 */             for (int z = 0; z < 2; z++) {
/* 062 */               project_numElements += args[z].numElements();
/* 063 */             }
/* 064 */             if (project_numElements > 2147483632) {
/* 065 */               throw new RuntimeException("Unsuccessful try to concat arrays with " + project_numElements +
/* 066 */                 " elements due to exceeding the array size limit 2147483632.");
/* 067 */             }
/* 068 */
/* 069 */             long project_size = UnsafeArrayData.calculateSizeOfUnderlyingByteArray(
/* 070 */               project_numElements,
/* 071 */               4);
/* 072 */             if (project_size > 2147483632) {
/* 073 */               throw new RuntimeException("Unsuccessful try to concat arrays with " + project_size +
/* 074 */                 " bytes of data due to exceeding the limit 2147483632 bytes" +
/* 075 */                 " for UnsafeArrayData.");
/* 076 */             }
/* 077 */
/* 078 */             byte[] project_array = new byte[(int)project_size];
/* 079 */             UnsafeArrayData project_arrayData = new UnsafeArrayData();
/* 080 */             Platform.putLong(project_array, 16, project_numElements);
/* 081 */             project_arrayData.pointTo(project_array, 16, (int)project_size);
/* 082 */             int project_counter = 0;
/* 083 */             for (int y = 0; y < 2; y++) {
/* 084 */               for (int z = 0; z < args[y].numElements(); z++) {
/* 085 */                 if (args[y].isNullAt(z)) {
/* 086 */                   project_arrayData.setNullAt(project_counter);
/* 087 */                 } else {
/* 088 */                   project_arrayData.setInt(
/* 089 */                     project_counter,
/* 090 */                     args[y].getInt(z)
/* 091 */                   );
/* 092 */                 }
/* 093 */                 project_counter++;
/* 094 */               }
/* 095 */             }
/* 096 */             return project_arrayData;
/* 097 */           }
/* 098 */         }.concat(project_args);
/* 099 */         boolean project_isNull = project_value == null;
```

### Non-primitive-type elements
```
val df = Seq(
  (Seq("aa" ,"bb"), Seq("ccc", "ddd")),
  (Seq("x", "y"), null)
).toDF("a", "b")
df.filter('a.isNotNull).select(concat('a, 'b)).debugCodegen()
```
Result:
```
/* 033 */         boolean inputadapter_isNull = inputadapter_row.isNullAt(0);
/* 034 */         ArrayData inputadapter_value = inputadapter_isNull ?
/* 035 */         null : (inputadapter_row.getArray(0));
/* 036 */
/* 037 */         if (!(!inputadapter_isNull)) continue;
/* 038 */
/* 039 */         ((org.apache.spark.sql.execution.metric.SQLMetric) references[0] /* numOutputRows */).add(1);
/* 040 */
/* 041 */         ArrayData[] project_args = new ArrayData[2];
/* 042 */
/* 043 */         if (!false) {
/* 044 */           project_args[0] = inputadapter_value;
/* 045 */         }
/* 046 */
/* 047 */         boolean inputadapter_isNull1 = inputadapter_row.isNullAt(1);
/* 048 */         ArrayData inputadapter_value1 = inputadapter_isNull1 ?
/* 049 */         null : (inputadapter_row.getArray(1));
/* 050 */         if (!inputadapter_isNull1) {
/* 051 */           project_args[1] = inputadapter_value1;
/* 052 */         }
/* 053 */
/* 054 */         ArrayData project_value = new Object() {
/* 055 */           public ArrayData concat(ArrayData[] args) {
/* 056 */             for (int z = 0; z < 2; z++) {
/* 057 */               if (args[z] == null) return null;
/* 058 */             }
/* 059 */
/* 060 */             long project_numElements = 0L;
/* 061 */             for (int z = 0; z < 2; z++) {
/* 062 */               project_numElements += args[z].numElements();
/* 063 */             }
/* 064 */             if (project_numElements > 2147483632) {
/* 065 */               throw new RuntimeException("Unsuccessful try to concat arrays with " + project_numElements +
/* 066 */                 " elements due to exceeding the array size limit 2147483632.");
/* 067 */             }
/* 068 */
/* 069 */             Object[] project_arrayObjects = new Object[(int)project_numElements];
/* 070 */             int project_counter = 0;
/* 071 */             for (int y = 0; y < 2; y++) {
/* 072 */               for (int z = 0; z < args[y].numElements(); z++) {
/* 073 */                 project_arrayObjects[project_counter] = args[y].getUTF8String(z);
/* 074 */                 project_counter++;
/* 075 */               }
/* 076 */             }
/* 077 */             return new org.apache.spark.sql.catalyst.util.GenericArrayData(project_arrayObjects);
/* 078 */           }
/* 079 */         }.concat(project_args);
/* 080 */         boolean project_isNull = project_value == null;
```

Author: mn-mikke <mrkAha12346github>

Closes #20858 from mn-mikke/feature/array-api-concat_arrays-to-master.
2018-04-20 14:58:11 +09:00
..
docs [SPARK-21866][ML][PYSPARK] Adding spark image reader 2017-11-22 15:45:45 -08:00
lib [SPARK-21278][PYSPARK] Upgrade to Py4J 0.10.6 2017-07-05 16:33:23 -07:00
pyspark [SPARK-23736][SQL] Extending the concat function to support array columns 2018-04-20 14:58:11 +09:00
test_coverage [SPARK-7721][PYTHON][TESTS] Adds PySpark coverage generation script 2018-01-22 22:12:50 +09:00
test_support [SPARK-19610][SQL] Support parsing multiline CSV files 2017-02-28 13:34:33 -08:00
.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-18652][PYTHON] Include the example data and third-party licenses in pyspark package. 2016-12-07 06:09:27 +08:00
pylintrc [SPARK-13596][BUILD] Move misc top-level build files into appropriate subdirs 2016-03-07 14:48:02 -08:00
README.md [MINOR][DOC] Fix some typos and grammar issues 2018-04-06 13:37:08 +08:00
run-tests [SPARK-8583] [SPARK-5482] [BUILD] Refactor python/run-tests to integrate with dev/run-tests module system 2015-06-27 20:24:34 -07:00
run-tests-with-coverage [SPARK-7721][PYTHON][TESTS] Adds PySpark coverage generation script 2018-01-22 22:12:50 +09:00
run-tests.py [SPARK-23300][TESTS] Prints out if Pandas and PyArrow are installed or not in PySpark SQL tests 2018-02-06 16:08:15 +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-23522][PYTHON] always use sys.exit over builtin exit 2018-03-08 20:38:34 +09:00

Apache Spark

Spark is a fast and general cluster computing system for Big Data. 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 Spark Streaming for stream processing.

http://spark.apache.org/

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Python Packaging

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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

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