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https://issues.apache.org/jira/browse/CALCITE-3077?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16843081#comment-16843081
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Feng Zhu commented on CALCITE-3077:
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I am working on this issue now, and look forward to hear some suggestions.
> Rewrite CUBE&ROLLUP&CUBE queries in SparkSqlDialect
> ---------------------------------------------------
>
> Key: CALCITE-3077
> URL: https://issues.apache.org/jira/browse/CALCITE-3077
> Project: Calcite
> Issue Type: Bug
> Components: core
> Affects Versions: 1.20.0
> Reporter: Feng Zhu
> Priority: Major
>
> *Backgroung:* we are building a platform that adopts Calcite to process
> (i.e., parse&validate&convert&optimize) SQL queries and then regenerate the
> final SQL. For the purpose of handling large volume data, we use the popular
> SparkSQL engine to execute the generated SQL query.
> However, we found a great part of real-world test cases failed, due to syntax
> differences of
> *_CUBE/ROLLUP/GROUPING SETS_* clauses. Spark SQL dialect supports only "WITH
> ROLLUP&CUBE" in the "GROUP BY" clause. The corresponding grammer [1] is
> defined as below.
> {code:java}
> aggregation
> : GROUP BY groupingExpressions+=expression (','
> groupingExpressions+=expression)* (
> WITH kind=ROLLUP
> | WITH kind=CUBE
> | kind=GROUPING SETS '(' groupingSet (',' groupingSet)* ')')?
> | GROUP BY kind=GROUPING SETS '(' groupingSet (',' groupingSet)* ')'
> ;
> {code}
> To fill this gap, I think we need to rewrite CUBE/ROLLUP/GROUPING SETS
> clauses in SparkSqlDialect, especially for some complex cases.
> {code:java}
> group by cube ((a, b), (c, d))
> group by cube(a,b), cube(c,d)
> {code}
> [1]https://github.com/apache/spark/blob/master/sql/catalyst/src/main/antlr4/org/apache/spark/sql/catalyst/parser/SqlBase.g4
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