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LakeShen commented on CALCITE-5889: ----------------------------------- The PR is ready,link:[https://github.com/apache/calcite/pull/3367] if someone have time, please help me to review it, thank you very much:) > Add the RelRule that converts Minus into UNION ALL..GROUP BY...WHERE > -------------------------------------------------------------------- > > Key: CALCITE-5889 > URL: https://issues.apache.org/jira/browse/CALCITE-5889 > Project: Calcite > Issue Type: New Feature > Components: core > Reporter: LakeShen > Assignee: LakeShen > Priority: Major > Labels: pull-request-available > Fix For: 1.36.0 > > > There are many projects that implement optimizers based on Calcite,our > optimizer is also based on Calcite. > Calcite has a lot of good rules in CoreRules.It has UnionToDistinctRule and > IntersectToDistinctRule RelRule ,UnionToDistinctRule is that converts > Union(all = false) to Union(all=true) + Aggregate,IntersectToDistinctRule is > that converts Intersect(all=false) to Union(all=true) + Aggregate + > Filter.None of these rules translate Minus to other RelNode combinations. > Normally, a computation engine does not have a Minus operator, so it is > common to convert Minus to some other relational algebra combination in the > optimizer.For example,in presto,it has the ImplementIntersectAndExceptAsUnion > PlanOptimizer that converts Minus to into UNION ALL..GROUP BY...WHERE. In > flink,it has the ReplaceMinusWithAntiJoinRule RelOptRule. In dremio-oss,it > has MinusToJoin RelOptRule.All of this rules,converts the Minus to other > composition of relational algebra. > Since there are no optimization rules for dealing with minus in calcite, > users of calcite generally need to write their own optimization rules for > dealing with Minus. > I think it makes sense to add the RelRule that converts Minus to other > composition of relational algebranto ,like UNION ALL.. GROUP BY... WHERE. So > for users of calcite,they don't have to go through the extra work of writing > rules for Minus to convert it to something else. -- This message was sent by Atlassian Jira (v8.20.10#820010)