Stamatis Zampetakis created HIVE-23479: ------------------------------------------
Summary: 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 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)