The parent DISTINCT is being removed over joins in particular situations. This is a regression from TEIID-3063 TEIID-3062.

Conditions:

• basic query structure is select distinct col from a join b on a.col2 = b.col2
• a sort merge join variant must have been planned
• the sort must not be pushed to one of the children
• the projection related conditions of TEIID-3062 / TEIID-3063 must be met
• there is a one to many relationship

The result is that the parent distinct will be inappropriately removed, such that the output of the join can contain repetition of the col value when it should be distinct.