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Haisheng Yuan commented on CALCITE-4705: ---------------------------------------- I don't know any other databases that support skew join hint besides these two. > Support hints like /*+ skewjoin(a(c0, c1)) */ > --------------------------------------------- > > Key: CALCITE-4705 > URL: https://issues.apache.org/jira/browse/CALCITE-4705 > Project: Calcite > Issue Type: Improvement > Components: core > Affects Versions: 1.27.0 > Reporter: jibiyr > Assignee: jibiyr > Priority: Minor > > Dear community, > calcite parse support hint now,but it can not parse hint like follow, > _*select /*+ skewjoin(a(c0, c1)) */ * from T0 a join T1 b on a.c0 = b.c0,*_ > this is the bnf which is calcite supported now, > {code:java} > // > hint: > hintName > | hintName '(' hintOptions ')' > hintOptions: > hintKVOption [, hintKVOption ]* > | optionName [, optionName ]* > | optionValue [, optionValue ]* > hintKVOption: > optionName '=' stringLiteral > | stringLiteral '=' stringLiteral > optionValue: > stringLiteral > | numericLiteral > {code} > I think the hintOptions should support the expression pattern,like a(c0,c1). > And this pattern can be parsed by spark/presto now. > -- This message was sent by Atlassian Jira (v8.20.10#820010)