You are viewing a plain text version of this content. The canonical link for it is here.

Posted to issues@spark.apache.org by "Apache Spark (Jira)" <ji...@apache.org> on 2022/10/31 18:15:00 UTC

[jira] [Assigned] (SPARK-40802) Enhance JDBC Connector to use PreparedStatement.getMetaData() to resolve schema instead of PreparedStatement.executeQuery()

     [ https://issues.apache.org/jira/browse/SPARK-40802?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Apache Spark reassigned SPARK-40802:
------------------------------------

    Assignee:     (was: Apache Spark)

> Enhance JDBC Connector to use PreparedStatement.getMetaData() to resolve schema instead of PreparedStatement.executeQuery()
> ---------------------------------------------------------------------------------------------------------------------------
>
>                 Key: SPARK-40802
>                 URL: https://issues.apache.org/jira/browse/SPARK-40802
>             Project: Spark
>          Issue Type: Improvement
>          Components: SQL
>    Affects Versions: 2.1.0
>            Reporter: Mingli Rui
>            Priority: Major
>   Original Estimate: 24h
>  Remaining Estimate: 24h
>
> Currently, Spark JDBC Connector uses *PreparedStatement.executeQuery()* to resolve the JDBCRelation's schema. The schema query is like *s"SELECT * FROM $table_or_query WHERE 1=0".*
> But it is not necessary to execute the query. It's enough to *prepare* the query. With preparing the statement, the query is parsed and compiled, but is not executed. It will be more efficient.
> So, it's better to use PreparedStatement.getMetaData() to resolve schema.



--
This message was sent by Atlassian Jira
(v8.20.10#820010)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscribe@spark.apache.org
For additional commands, e-mail: issues-help@spark.apache.org