spark-instrumented-optimizer/sql
Kazuaki Ishizaki 79b05481a2 [SPARK-26508][CORE][SQL] Address warning messages in Java reported at lgtm.com
## What changes were proposed in this pull request?

This PR addresses warning messages in Java files reported at [lgtm.com](https://lgtm.com).

[lgtm.com](https://lgtm.com) provides automated code review of Java/Python/JavaScript files for OSS projects. [Here](https://lgtm.com/projects/g/apache/spark/alerts/?mode=list&severity=warning) are warning messages regarding Apache Spark project.

This PR addresses the following warnings:

- Result of multiplication cast to wider type
- Implicit narrowing conversion in compound assignment
- Boxed variable is never null
- Useless null check

NOTE: `Potential input resource leak` looks false positive for now.

## How was this patch tested?

Existing UTs

Closes #23420 from kiszk/SPARK-26508.

Authored-by: Kazuaki Ishizaki <ishizaki@jp.ibm.com>
Signed-off-by: Sean Owen <sean.owen@databricks.com>
2019-01-01 22:37:28 -06:00
..
catalyst [SPARK-26508][CORE][SQL] Address warning messages in Java reported at lgtm.com 2019-01-01 22:37:28 -06:00
core [SPARK-26227][R] from_[csv|json] should accept schema_of_[csv|json] in R API 2019-01-02 08:01:34 +08:00
hive [SPARK-26374][TEST][SQL] Enable TimestampFormatter in HadoopFsRelationTest 2019-01-02 07:59:32 +08:00
hive-thriftserver [SPARK-26090][CORE][SQL][ML] Resolve most miscellaneous deprecation and build warnings for Spark 3 2018-11-19 09:16:42 -06:00
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-21485][FOLLOWUP][SQL][DOCS] Describes examples and arguments separately, and note/since in SQL built-in function documentation 2017-08-05 10:10:56 -07:00
mkdocs.yml [SPARK-21485][SQL][DOCS] Spark SQL documentation generation for built-in functions 2017-07-26 09:38:51 -07:00
README.md [MINOR][DOC] Fix some typos and grammar issues 2018-04-06 13:37:08 +08:00

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.