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https://issues.apache.org/jira/browse/CALCITE-4742?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17401064#comment-17401064
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duan xiong commented on CALCITE-4742:
-------------------------------------
[~ivandasch] Sorry. Yes. According to the existing results, there is a
problem. And the rewrite sql result has some problem(only one column and it
seems too complicated).SOME_EQ rewrite to in makes me confuse. Thanks for your
reminder very much. So let's think about this：
{code:java}
columnName = some(value1,value2,value3) {code}
which means
{code:java}
columnName = value1 or columnName = value2 or columnName = value3{code}
So we need find a converse relation algebra to express this:
{code:java}
columnName <> some(value1,value2,value3) {code}
==>
{code:java}
(columnName != value1 or columnName != value2 or columnName != value3){code}
==>
{code:java}
!(column == value1 and column == value2 and column ==value3){code}
If this expression is right which means only one value is meaning.(the
columnName's value can't equals two different value meantime).(If I am wrong,
Please let me know)
Then maybe we can rewrite a easy sql according to this result.
> Implement NOT EQUALS in some subquery
> -------------------------------------
>
> Key: CALCITE-4742
> URL: https://issues.apache.org/jira/browse/CALCITE-4742
> Project: Calcite
> Issue Type: Bug
> Components: core
> Reporter: Ivan Daschinsky
> Assignee: duan xiong
> Priority: Major
> Fix For: 1.28.0
>
>
> When executing
> {code}
> select * from "scott".emp where empno <> any (select 10);
> {code}
> with assertions, got assertion error
> {code}
> ---
> > java.lang.AssertionError
> > at
> > org.apache.calcite.rel.rules.SubQueryRemoveRule.rewriteSome(SubQueryRemoveRule.java:170)
> > at
> > org.apache.calcite.rel.rules.SubQueryRemoveRule.apply(SubQueryRemoveRule.java:92)
> > at
> > org.apache.calcite.rel.rules.SubQueryRemoveRule.matchFilter(SubQueryRemoveRule.java:637)
> > at
> > org.apache.calcite.rel.rules.SubQueryRemoveRule.access$100(SubQueryRemoveRule.java:71)
> > at
> > org.apache.calcite.rel.rules.SubQueryRemoveRule$Config.lambda$static$3(SubQueryRemoveRule.java:701)
> > at
> > org.apache.calcite.rel.rules.SubQueryRemoveRule.onMatch(SubQueryRemoveRule.java:82)
> > at
> > org.apache.calcite.plan.AbstractRelOptPlanner.fireRule(AbstractRelOptPlanner.java:341)
> > at org.apache.calcite.plan.hep.HepPlanner.applyRule(HepPlanner.java:565)
> > at
> > org.apache.calcite.plan.hep.HepPlanner.applyRules(HepPlanner.java:428)
> > at
> > org.apache.calcite.plan.hep.HepPlanner.executeInstruction(HepPlanner.java:282)
> > at
> > org.apache.calcite.plan.hep.HepInstruction$RuleCollection.execute(HepInstruction.java:77)
> > at
> > org.apache.calcite.plan.hep.HepPlanner.executeProgram(HepPlanner.java:208)
> > at
> > org.apache.calcite.plan.hep.HepPlanner.findBestExp(HepPlanner.java:195)
> > at org.apache.calcite.tools.Programs.lambda$of$0(Programs.java:176)
> > at
> > org.apache.calcite.tools.Programs$SequenceProgram.run(Programs.java:335)
> > at org.apache.calcite.prepare.Prepare.optimize(Prepare.java:172)
> > at org.apache.calcite.prepare.Prepare.prepareSql(Prepare.java:306)
> > at org.apache.calcite.prepare.Prepare.prepareSql(Prepare.java:215)
> > at
> > org.apache.calcite.prepare.CalcitePrepareImpl.prepare2_(CalcitePrepareImpl.java:647)
> > at
> > org.apache.calcite.prepare.CalcitePrepareImpl.prepare_(CalcitePrepareImpl.java:513)
> > at
> > org.apache.calcite.prepare.CalcitePrepareImpl.prepareSql(CalcitePrepareImpl.java:483)
> > at
> > org.apache.calcite.jdbc.CalciteConnectionImpl.parseQuery(CalciteConnectionImpl.java:249)
> > at
> > org.apache.calcite.jdbc.CalciteMetaImpl.prepareAndExecute(CalciteMetaImpl.java:623)
> {code}
> This query cannot be rewritten as IN query, so it goes to
> {{SubQueryRemoveRule.rewriteSome}}. Current logic in this method doesn't work
> on this case and produce wrong plan.
> This query should be rewritten to something like this:
> {code}
> select distinct(e.*) from "scott".emp as e inner join (select 10 as empno)
> as q on e.empno <> q.empno;
> {code}
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