SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 2)
    Identifier t1.a (alias t1_a)
    Identifier t2.a (alias t2_a)
   TablesInSelectQuery (children 2)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier table1 (alias t1)
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      TableIdentifier table2 (alias t2)
     TableJoin (children 1)
      Function and (children 1)
       ExpressionList (children 3)
        Function equals (children 1)
         ExpressionList (children 2)
          Identifier table1.a
          Identifier t2_a
        Function equals (children 1)
         ExpressionList (children 2)
          Identifier t1.a
          Identifier t2_a
        Function equals (children 1)
         ExpressionList (children 2)
          Identifier t1_a
          Identifier t2_a
   ExpressionList (children 1)
    OrderByElement (children 1)
     Identifier all