SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Asterisk
   TablesInSelectQuery (children 2)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier t1
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      TableIdentifier t2
     TableJoin (children 1)
      Function and (children 1)
       ExpressionList (children 2)
        Function isNotDistinctFrom (children 1)
         ExpressionList (children 2)
          Identifier t1.x
          Identifier t2.x
        Function or (children 1)
         ExpressionList (children 2)
          Function equals (children 1)
           ExpressionList (children 2)
            Identifier t1.x
            Identifier t1.y
          Function and (children 1)
           ExpressionList (children 2)
            Function isNull (children 1)
             ExpressionList (children 1)
              Identifier t1.x
            Function isNull (children 1)
             ExpressionList (children 1)
              Identifier t1.y
   ExpressionList (children 1)
    OrderByElement (children 1)
     Identifier t1.x
