spark-instrumented-optimizer/sql
woyumen4597 f44608a8c0 [SPARK-34800][SQL] Use fine-grained lock in SessionCatalog.tableExists
### What changes were proposed in this pull request?
Use fine-grained lock in SessionCatalog.tableExists, in order to lock currentDB variable rather than lock `tableExists` method which will block inner external catalog's behaviour.

### Why are the changes needed?
We have modified the underlying hive meta store which a different hive  database is placed in its own shard for performance. However, we found that the synchronized lock  limits the concurrency.

### How was this patch tested?
Existing tests.

Closes #31891 from woyumen4597/SPARK-34800.

Authored-by: woyumen4597 <woyumen4597@gmail.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2021-03-22 09:03:46 +00:00
..
catalyst [SPARK-34800][SQL] Use fine-grained lock in SessionCatalog.tableExists 2021-03-22 09:03:46 +00:00
core [SPARK-34700][SQL] SessionCatalog's temporary view related APIs should take/return more concrete types 2021-03-22 08:17:54 +00:00
hive [SPARK-34700][SQL] SessionCatalog's temporary view related APIs should take/return more concrete types 2021-03-22 08:17:54 +00:00
hive-thriftserver [SPARK-34700][SQL] SessionCatalog's temporary view related APIs should take/return more concrete types 2021-03-22 08:17:54 +00:00
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-31550][SQL][DOCS] Set nondeterministic configurations with general meanings in sql configuration doc 2020-04-27 17:08:52 +09:00
gen-sql-functions-docs.py [SPARK-31562][SQL] Update ExpressionDescription for substring, current_date, and current_timestamp 2020-04-26 11:46:52 -07:00
mkdocs.yml [SPARK-30731] Update deprecated Mkdocs option 2020-02-19 17:28:58 +09:00
README.md [SPARK-30510][SQL][DOCS] Publicly document Spark SQL configuration options 2020-02-09 19:20:47 +09:00

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 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.