8bd27025b7
## What changes were proposed in this pull request? `ColumnVector`s store string data in one big byte array. Since the array size is capped at just under Integer.MAX_VALUE, a single `ColumnVector` cannot store more than 2GB of string data. But since the Parquet files commonly contain large blobs stored as strings, and `ColumnVector`s by default carry 4096 values, it's entirely possible to go past that limit. In such cases a negative capacity is requested from `WritableColumnVector.reserve()`. The call succeeds (requested capacity is smaller than already allocated capacity), and consequently `java.lang.ArrayIndexOutOfBoundsException` is thrown when the reader actually attempts to put the data into the array. This change introduces a simple check for integer overflow to `WritableColumnVector.reserve()` which should help catch the error earlier and provide more informative exception. Additionally, the error message in `WritableColumnVector.throwUnsupportedException()` was corrected, as it previously encouraged users to increase rather than reduce the batch size. ## How was this patch tested? New units tests were added. Author: Ala Luszczak <ala@databricks.com> Closes #21206 from ala/overflow-reserve. |
||
|---|---|---|
| .. | ||
| 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 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.