[jira] [Commented] (HIVE-23479) Avoid regenerating JdbcSchema for every table in a query
[ https://issues.apache.org/jira/browse/HIVE-23479?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17429485#comment-17429485 ] Soumyakanti Das commented on HIVE-23479: Fixed with HIVE-25530. Resolving issue. > Avoid regenerating JdbcSchema for every table in a query > > > Key: HIVE-23479 > URL: https://issues.apache.org/jira/browse/HIVE-23479 > Project: Hive > Issue Type: Improvement > Components: Query Planning >Reporter: Stamatis Zampetakis >Priority: Major > > Currently {{CalcitePlanner}} generates a complete {{JdbcSchema}} for every > {{JdbcTable}} in the query. > https://github.com/apache/hive/blob/master/ql/src/java/org/apache/hadoop/hive/ql/parse/CalcitePlanner.java#L3174 > This wastes some resources since every call to {{JdbcSchema#getTable}} needs > to communicate with the database to bring back the tables belonging to the > schema. Moreover, the fact that a schema is created during planning is > counter-intuitive since in principle the schema shouldn't change. -- This message was sent by Atlassian Jira (v8.3.4#803005)
[jira] [Commented] (HIVE-23479) Avoid regenerating JdbcSchema for every table in a query
[ https://issues.apache.org/jira/browse/HIVE-23479?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17108721#comment-17108721 ] Stamatis Zampetakis commented on HIVE-23479: Credits for this discovery go to [~kgyrtkirk]! :) > Avoid regenerating JdbcSchema for every table in a query > > > Key: HIVE-23479 > URL: https://issues.apache.org/jira/browse/HIVE-23479 > Project: Hive > Issue Type: Improvement > Components: Query Planning >Reporter: Stamatis Zampetakis >Priority: Major > > Currently {{CalcitePlanner}} generates a complete {{JdbcSchema}} for every > {{JdbcTable}} in the query. > https://github.com/apache/hive/blob/master/ql/src/java/org/apache/hadoop/hive/ql/parse/CalcitePlanner.java#L3174 > This wastes some resources since every call to {{JdbcSchema#getTable}} needs > to communicate with the database to bring back the tables belonging to the > schema. Moreover, the fact that a schema is created during planning is > counter-intuitive since in principle the schema shouldn't change. -- This message was sent by Atlassian Jira (v8.3.4#803005)