tree 59ce67d4bfad0605751e5722113dd0e91dea5885
parent e5477e7cda4ed9747d970b830d1fe9c53c49f2f3
author Rafay <rafay@dremio.com> 1622750048 -0700
committer amaliujia <amaliujia@163.com> 1623621289 -0700

[CALCITE-4636] Switch out of agg mode when constructing RelCollation for aggregate functions (Rafay)

When we create RelCollation for WITHIN GROUP clause, we try to find the node in the group set first, which returns a RexNode which references the current group set instead of the field in the input. If the field is present in the group set, its index may not match with the field index in the input node, hence we get a mismatch, and then we wrongly add a new expression in SqlToRelConverter.AggConverter#lookupOrCreateGroupExpr method.
The solution is to disable the agg mode, which will force the SqlToRelConverter.Blackboard#convertExpression function to return the correct RexNode referencing from the input, without looking in the grouping set.