2333a34d39
This commit adds the `cascadeTruncate` option to the JDBC datasource API, for databases that support this functionality (PostgreSQL and Oracle at the moment). This allows for applying a cascading truncate that affects tables that have foreign key constraints on the table being truncated. ## What changes were proposed in this pull request? Add `cascadeTruncate` option to JDBC datasource API. Allow this to affect the `TRUNCATE` query for databases that support this option. ## How was this patch tested? Existing tests for `truncateQuery` were updated. Also, an additional test was added to ensure that the correct syntax was applied, and that enabling the config for databases that do not support this option does not result in invalid queries. Author: Daniel van der Ende <daniel.vanderende@gmail.com> Closes #20057 from danielvdende/SPARK-22880. |
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catalyst | ||
core | ||
hive | ||
hive-thriftserver | ||
create-docs.sh | ||
gen-sql-markdown.py | ||
mkdocs.yml | ||
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 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
.