SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Asterisk
   TablesInSelectQuery (children 2)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (alias t1) (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 2)
          ExpressionList (children 3)
           Identifier key3 (alias c)
           Identifier key1 (alias a)
           Identifier key2 (alias b)
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             TableIdentifier t1
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      TableIdentifier tj
     TableJoin (children 1)
      Function and (children 1)
       ExpressionList (children 3)
        Function equals (children 1)
         ExpressionList (children 2)
          Identifier t1.a
          Identifier tj.key1
        Function equals (children 1)
         ExpressionList (children 2)
          Identifier t1.b
          Identifier tj.key2
        Function equals (children 1)
         ExpressionList (children 2)
          Identifier t1.c
          Identifier tj.key3
   ExpressionList (children 1)
    OrderByElement (children 1)
     Identifier t1.a
