82b4f753a0
### What changes were proposed in this pull request?
This PR adds `SparkSession.executeCommand` API for external datasource to execute a random command like
```
val df = spark.executeCommand("xxxCommand", "xxxSource", "xxxOptions")
```
Note that the command doesn't execute in Spark, but inside an external execution engine depending on data source. And it will be eagerly executed after `executeCommand` called and the returned `DataFrame` will contain the output of the command(if any).
### Why are the changes needed?
This can be useful when user wants to execute some commands out of Spark. For example, executing custom DDL/DML command for JDBC, creating index for ElasticSearch, creating cores for Solr and so on(as HyukjinKwon suggested).
Previously, user needs to use an option to achieve the goal, e.g. `spark.read.format("xxxSource").option("command", "xxxCommand").load()`, which is kind of cumbersome. With this change, it can be more convenient for user to achieve the same goal.
### Does this PR introduce any user-facing change?
Yes, new API from `SparkSession` and a new interface `ExternalCommandRunnableProvider`.
### How was this patch tested?
Added a new test suite.
Closes #27199 from Ngone51/dev-executeCommand.
Lead-authored-by: yi.wu <yi.wu@databricks.com>
Co-authored-by: Xiao Li <gatorsmile@gmail.com>
Co-authored-by: Wenchen Fan <wenchen@databricks.com>
Signed-off-by: Xiao Li <gatorsmile@gmail.com>
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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 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.