Explain EXPLAIN AST (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 1)
    ExpressionList (children 1)
     Function or (children 1)
      ExpressionList (children 2)
       Function isNotDistinctFrom (children 1)
        ExpressionList (children 2)
         Literal Bool_0
         Literal Bool_1
       Literal Bool_1
