spark-instrumented-optimizer/sql
hyukjinkwon 24100f162d [SPARK-16848][SQL] Check schema validation for user-specified schema in jdbc and table APIs
## What changes were proposed in this pull request?

This PR proposes to throw an exception for both jdbc APIs when user specified schemas are not allowed or useless.

**DataFrameReader.jdbc(...)**

``` scala
spark.read.schema(StructType(Nil)).jdbc(...)
```

**DataFrameReader.table(...)**

```scala
spark.read.schema(StructType(Nil)).table("usrdb.test")
```

## How was this patch tested?

Unit test in `JDBCSuite` and `DataFrameReaderWriterSuite`.

Author: hyukjinkwon <gurwls223@gmail.com>

Closes #14451 from HyukjinKwon/SPARK-16848.
2017-01-11 21:03:48 -08:00
..
catalyst [SPARK-19132][SQL] Add test cases for row size estimation and aggregate estimation 2017-01-11 15:00:58 -08:00
core [SPARK-16848][SQL] Check schema validation for user-specified schema in jdbc and table APIs 2017-01-11 21:03:48 -08:00
hive [SPARK-18801][SQL] Support resolve a nested view 2017-01-11 13:44:07 -08:00
hive-thriftserver [SPARK-18857][SQL] Don't use Iterator.duplicate for incrementalCollect in Thrift Server 2017-01-10 13:27:55 +00:00
README.md [SPARK-16557][SQL] Remove stale doc in sql/README.md 2016-07-14 19:24:42 -07:00

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 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.