Andrew Tsvelodub created CALCITE-2790:
-----------------------------------------
Summary: AggregateJoinTransposeRule incorrectly pushes down
distinct count into join
Key: CALCITE-2790
URL: https://issues.apache.org/jira/browse/CALCITE-2790
Project: Calcite
Issue Type: Bug
Components: core
Affects Versions: 1.18.0
Reporter: Andrew Tsvelodub
Assignee: Julian Hyde
AggregateJoinTransposeRule.EXTENDED can push down aggregate functions into the
join.
For Distinct Count (and other distinct aggregate functions) this should not be
performed the same way as for simple count, since distinct count is not a
decomposable function. [1]
While this can be done in theory, by adding the distinct column to the list of
groups in below aggregate[2], I want to fix the buggy behavior first, before
trying to improve the existing rule.
[1] Dynamic Programming: The Next Step, M. Eich, G. Moerkotte
([https://ub-madoc.bib.uni-mannheim.de/37228/1/main.pdf)]
[2] Including Group-By in Query Optimization, S. Chaudhuri, K. Shim
([https://pdfs.semanticscholar.org/3079/5447cec18753254edbbd7839f0afa58b2a39.pdf)]
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
