fac469e2e0
### What changes were proposed in this pull request? The rule ReuseExchange optimization rule will look for instances of Exchange that have the same plan and convert dedupe them to them to a ReuseExchangeExec instance. In the current Spark codebase all Exchange instances are row based, but if we use the spark.sql.extensions config to put in our own columnar based exchange implementation reuse will throw an exception saying that there was a columnar mismatch. ### Why are the changes needed? Without it Reused Columnar Exchanges throw an exception ### Does this PR introduce any user-facing change? No ### How was this patch tested? I tested this patch by running it against a query that was showing this exact issue and it fixed it. I also added a very simple unit test that shows the issue. Closes #25499 from revans2/reused-columnar-exchange. Authored-by: Robert (Bobby) Evans <bobby@apache.org> Signed-off-by: Wenchen Fan <wenchen@databricks.com> |
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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
.