spark-instrumented-optimizer/sql
Terry Kim beae14d5ed [SPARK-30104][SQL] Fix catalog resolution for 'global_temp'
### What changes were proposed in this pull request?

`global_temp` is used as a database name to access global temp views. The current catalog lookup logic considers only the first element of multi-part name when it resolves a catalog. This results in using the session catalog even `global_temp` is used as a table name under v2 catalog. This PR addresses this by making sure multi-part name has two elements before using the session catalog.

### Why are the changes needed?

Currently, 'global_temp' can be used as a table name in certain commands (CREATE) but not in others (DESCRIBE):
```
// Assume "spark.sql.globalTempDatabase" is set to "global_temp".
sql(s"CREATE TABLE testcat.t (id bigint, data string) USING foo")
sql(s"CREATE TABLE testcat.global_temp (id bigint, data string) USING foo")
sql("USE testcat")

sql(s"DESCRIBE TABLE t").show
+---------------+---------+-------+
|       col_name|data_type|comment|
+---------------+---------+-------+
|             id|   bigint|       |
|           data|   string|       |
|               |         |       |
| # Partitioning|         |       |
|Not partitioned|         |       |
+---------------+---------+-------+

sql(s"DESCRIBE TABLE global_temp").show
org.apache.spark.sql.AnalysisException: Table not found: global_temp;;
  'DescribeTable 'UnresolvedV2Relation [global_temp], org.apache.spark.sql.connector.InMemoryTableSessionCatalog2f1af64f, `global_temp`, false
  at org.apache.spark.sql.catalyst.analysis.CheckAnalysis.failAnalysis(CheckAnalysis.scala:47)
  at org.apache.spark.sql.catalyst.analysis.CheckAnalysis.failAnalysis$(CheckAnalysis.scala:46)
  at org.apache.spark.sql.catalyst.analysis.Analyzer.failAnalysis(Analyzer.scala:122)
```

### Does this PR introduce any user-facing change?

Yes, `sql(s"DESCRIBE TABLE global_temp").show` in the above example now displays:
```
+---------------+---------+-------+
|       col_name|data_type|comment|
+---------------+---------+-------+
|             id|   bigint|       |
|           data|   string|       |
|               |         |       |
| # Partitioning|         |       |
|Not partitioned|         |       |
+---------------+---------+-------+
```
instead of throwing an exception.

### How was this patch tested?

Added new tests.

Closes #26741 from imback82/global_temp.

Authored-by: Terry Kim <yuminkim@gmail.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2019-12-11 16:56:42 +08:00
..
catalyst [SPARK-30104][SQL] Fix catalog resolution for 'global_temp' 2019-12-11 16:56:42 +08:00
core [SPARK-30104][SQL] Fix catalog resolution for 'global_temp' 2019-12-11 16:56:42 +08:00
hive [SPARK-30159][SQL][FOLLOWUP] Fix lint-java via removing unnecessary imports 2019-12-09 08:57:20 -08:00
hive-thriftserver [SPARK-30125][SQL] Remove PostgreSQL dialect 2019-12-11 01:22:34 +08:00
create-docs.sh [MINOR][DOCS] Minor doc fixes related with doc build and uses script dir in SQL doc gen script 2017-08-26 13:56:24 +09:00
gen-sql-markdown.py [SPARK-27328][SQL] Add 'deprecated' in ExpressionDescription for extended usage and SQL doc 2019-04-09 13:49:42 +08:00
mkdocs.yml [SPARK-21485][SQL][DOCS] Spark SQL documentation generation for built-in functions 2017-07-26 09:38:51 -07:00
README.md [SPARK-28980][CORE][SQL][STREAMING][MLLIB] Remove most items deprecated in Spark 2.2.0 or earlier, for Spark 3 2019-09-09 10:19:40 -05:00

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.