ODIn/spark-instrumented-optimizer
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity
spark-instrumented-optimizer/sql
History
Jungtaek Lim dcee7a65fd [SPARK-34892][SS] Introduce MergingSortWithSessionWindowStateIterator sorting input rows and rows in state efficiently 
Introduction: this PR is a part of SPARK-10816 (EventTime based sessionization (session window)). Please refer #31937 to see the overall view of the code change. (Note that code diff could be diverged a bit.)

### What changes were proposed in this pull request?

This PR introduces MergingSortWithSessionWindowStateIterator, which does "merge sort" between input rows and sessions in state based on group key and session's start time.

Note that the iterator does merge sort among input rows and sessions grouped by grouping key. The iterator doesn't provide sessions in state which keys don't exist in input rows. For input rows, the iterator will provide all rows regardless of the existence of matching sessions in state.

MergingSortWithSessionWindowStateIterator works on the precondition that given iterator is sorted by "group keys + start time of session window", and the iterator still retains the characteristic of the sort.

### Why are the changes needed?

This part is a one of required on implementing SPARK-10816.

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

No.

### How was this patch tested?

New UT added.

Closes #33077 from HeartSaVioR/SPARK-34892-SPARK-10816-PR-31570-part-4.

Authored-by: Jungtaek Lim <kabhwan.opensource@gmail.com>
Signed-off-by: Jungtaek Lim <kabhwan.opensource@gmail.com>
(cherry picked from commit 12a576f175)
Signed-off-by: Jungtaek Lim <kabhwan.opensource@gmail.com>
2021-07-14 18:48:05 +09:00
..
catalyst [SPARK-36130][SQL] UnwrapCastInBinaryComparison should skip In expression when in.list contains an expression that is not literal 2021-07-14 15:57:23 +08:00
core [SPARK-34892][SS] Introduce MergingSortWithSessionWindowStateIterator sorting input rows and rows in state efficiently 2021-07-14 18:48:05 +09:00
hive [SPARK-36012][SQL] Add null flag in SHOW CREATE TABLE 2021-07-09 01:21:57 +08:00
hive-thriftserver [SPARK-35749][SPARK-35773][SQL] Parse unit list interval literals as tightest year-month/day-time interval types 2021-07-13 18:55:22 +08:00
create-docs.sh [SPARK-34010][SQL][DODCS] Use python3 instead of python in SQL documentation build 2021-01-05 19:48:10 +09:00
gen-sql-api-docs.py [SPARK-34747][SQL][DOCS] Add virtual operators to the built-in function document 2021-03-19 10:19:26 +09:00
gen-sql-config-docs.py [SPARK-32194][PYTHON] Use proper exception classes instead of plain Exception 2021-05-26 11:54:40 +09:00
gen-sql-functions-docs.py
mkdocs.yml
README.md

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 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.