Seems `root.project()` works, thanks a lot!
Regards! Aron Tao JiaTao Tao <[email protected]> 于2020年3月5日周四 上午11:05写道： > Thanks, Julian > > I can see the fields in RelRoot, and I'm a little confused, I want to > use RelVisitor to visit the RelNode, and here comes the RelRoot, any advice > to deal with RelRoot when using RelVisitor? > > > Regards! > > Aron Tao > > > Julian Hyde <[email protected]> 于2020年3月5日周四 上午2:03写道： > >> There is a class RelRoot that wraps the top-most RelNode, and projects >> away columns that are only used for sorting. Read through >> https://issues.apache.org/jira/browse/CALCITE-2999 < >> https://issues.apache.org/jira/browse/CALCITE-2999>, where someone had >> the same misunderstanding that you have. >> >> >> > On Mar 4, 2020, at 3:43 AM, JiaTao Tao <[email protected]> wrote: >> > >> > SQL; >> > ``` >> > SELECT u.ID, u.NAME >> > FROM USERS u >> > ORDER BY u.AGE >> > ``` >> > >> > PLAN: >> > ``` >> > LogicalSort(sort0=[$2], dir0=[ASC]) >> > LogicalProject(ID=[$0], NAME=[$1], AGE=[$2]) >> > EnumerableTableScan(table=[[RECR, USERS]]) >> > ``` >> > Plan's row type: RecordType(INTEGER ID, VARCHAR NAME, INTEGER AGE) >> > >> > But the SQL only project ID and NAME, there should be a LogicalProject >> > (ID, NAME) on LogicalSort. Is this by design? And what about this extra >> > column? >> > >> > >> > >> > Regards! >> > >> > Aron Tao >> >>
