3e48f3b9ee
## What changes were proposed in this pull request? In a kerberized cluster, when Spark reads a file path (e.g. `people.json`), it warns with a wrong warning message during looking up `people.json/_spark_metadata`. The root cause of this situation is the difference between `LocalFileSystem` and `DistributedFileSystem`. `LocalFileSystem.exists()` returns `false`, but `DistributedFileSystem.exists` raises `org.apache.hadoop.security.AccessControlException`. ```scala scala> spark.version res0: String = 2.4.0-SNAPSHOT scala> spark.read.json("file:///usr/hdp/current/spark-client/examples/src/main/resources/people.json").show +----+-------+ | age| name| +----+-------+ |null|Michael| | 30| Andy| | 19| Justin| +----+-------+ scala> spark.read.json("hdfs:///tmp/people.json") 18/02/15 05:00:48 WARN streaming.FileStreamSink: Error while looking for metadata directory. 18/02/15 05:00:48 WARN streaming.FileStreamSink: Error while looking for metadata directory. ``` After this PR, ```scala scala> spark.read.json("hdfs:///tmp/people.json").show +----+-------+ | age| name| +----+-------+ |null|Michael| | 30| Andy| | 19| Justin| +----+-------+ ``` ## How was this patch tested? Manual. Author: Dongjoon Hyun <dongjoon@apache.org> Closes #20616 from dongjoon-hyun/SPARK-23434. |
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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 allows 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
.