DescribeQuery (children 1)
 TableExpression (children 1)
  Subquery (children 1)
   SelectWithUnionQuery (children 1)
    ExpressionList (children 1)
     SelectQuery (children 2)
      ExpressionList (children 6)
       Identifier id
       Identifier value
       Identifier t1.id
       Identifier t1.value
       Identifier t2.id
       Identifier t2.value
      TablesInSelectQuery (children 2)
       TablesInSelectQueryElement (children 1)
        TableExpression (children 1)
         TableIdentifier test_table_join_1 (alias t1)
       TablesInSelectQueryElement (children 2)
        TableExpression (children 1)
         TableIdentifier test_table_join_2 (alias t2)
        TableJoin (children 1)
         ExpressionList (children 2)
          Identifier id
          Identifier value
