spark-instrumented-optimizer/sql
Sean Owen b148bd5ccb [SPARK-28519][SQL] Use StrictMath log, pow functions for platform independence
## What changes were proposed in this pull request?

See discussion on the JIRA (and dev). At heart, we find that math.log and math.pow can actually return slightly different results across platforms because of hardware optimizations. For the actual SQL log and pow functions, I propose that we should use StrictMath instead to ensure the answers are already the same. (This should have the benefit of helping tests pass on aarch64.)

Further, the atanh function (which is not part of java.lang.Math) can be implemented in a slightly different and more accurate way.

## How was this patch tested?

Existing tests (which will need to be changed).
Some manual testing locally to understand the numeric issues.

Closes #25279 from srowen/SPARK-28519.

Authored-by: Sean Owen <sean.owen@databricks.com>
Signed-off-by: Sean Owen <sean.owen@databricks.com>
2019-08-02 10:55:44 -05:00
..
catalyst [SPARK-28519][SQL] Use StrictMath log, pow functions for platform independence 2019-08-02 10:55:44 -05:00
core [SPARK-28519][SQL] Use StrictMath log, pow functions for platform independence 2019-08-02 10:55:44 -05:00
hive [SPARK-25474][SQL] Support spark.sql.statistics.fallBackToHdfs in data source tables 2019-07-28 15:35:37 -07:00
hive-thriftserver [SPARK-28510][SQL] Implement Spark's own GetFunctionsOperation 2019-08-02 08:50:42 -07:00
create-docs.sh [MINOR][DOCS] Minor doc fixes related with doc build and uses script dir in SQL doc gen script 2017-08-26 13:56:24 +09:00
gen-sql-markdown.py [SPARK-27328][SQL] Add 'deprecated' in ExpressionDescription for extended usage and SQL doc 2019-04-09 13:49:42 +08:00
mkdocs.yml
README.md [SPARK-28473][DOC] Stylistic consistency of build command in README 2019-07-23 16:29:46 -07:00

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 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 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.