jin xing created CALCITE-3256: --------------------------------- Summary: Add ProjectOnProjectToProjectUnifyRule for materialization matching. Key: CALCITE-3256 URL: https://issues.apache.org/jira/browse/CALCITE-3256 Project: Calcite Issue Type: Improvement Components: core Reporter: jin xing Assignee: jin xing
In current implementation of rules in SubstitutionVisitor.java & MaterializedViewSubstitutionVisitor.java, it's quite common to add a compensating Project on top of child node of target(MV-rel) during matching. But afterwards the next round matching should be able to handle such a compensated Project and match upward along the plan tree. Otherwise we fail the matching. After all, the goal of matching is to transform the query and let a complete 'target' show up in the transformed query plan. I found cases where the compensated Project cannot be properly handled. {code:java} MV: select deptno, sum(salary) + 2, sum(commission) from emps group by deptno Query: select deptno, sum(salary) + 2 from emps group by deptno {code} After matching of the Aggregates, a compensating Project is added, but afterwards matching fails to handle it. -- This message was sent by Atlassian JIRA (v7.6.14#76016)