f984ec75ed
## What changes were proposed in this pull request? Spark SQL returns NULL for a column whose Hive metastore schema and Parquet schema are in different letter cases, regardless of spark.sql.caseSensitive set to true or false. This PR aims to add case-insensitive field resolution for ParquetFileFormat. * Do case-insensitive resolution only if Spark is in case-insensitive mode. * Field resolution should fail if there is ambiguity, i.e. more than one field is matched. ## How was this patch tested? Unit tests added. Closes #22148 from seancxmao/SPARK-25132-Parquet. Authored-by: seancxmao <seancxmao@gmail.com> Signed-off-by: hyukjinkwon <gurwls223@apache.org> |
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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
.