3c683434fa
### What changes were proposed in this pull request? As described in #32831, Spark has compatible issues when querying a view created by an older version. The root cause is that Spark changed the auto-generated alias name. To avoid this in the future, we could ask the user to specify explicit column names when creating a view. ### Why are the changes needed? Avoid compatible issue when querying a view ### Does this PR introduce _any_ user-facing change? Yes. User will get error when running query below after this change ``` CREATE OR REPLACE VIEW v AS SELECT CAST(t.a AS INT), to_date(t.b, 'yyyyMMdd') FROM t ``` ### How was this patch tested? not yet Closes #32832 from linhongliu-db/SPARK-35686-no-auto-alias. Authored-by: Linhong Liu <linhong.liu@databricks.com> Signed-off-by: Wenchen Fan <wenchen@databricks.com> |
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.. | ||
catalyst | ||
core | ||
hive | ||
hive-thriftserver | ||
create-docs.sh | ||
gen-sql-api-docs.py | ||
gen-sql-config-docs.py | ||
gen-sql-functions-docs.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 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.