DescribeQuery (children 1)
 TableExpression (children 1)
  Subquery (children 1)
   SelectWithUnionQuery (children 1)
    ExpressionList (children 1)
     SelectQuery (children 2)
      ExpressionList (children 2)
       QualifiedColumnsRegexpMatcher (children 1)
        Identifier test_table
       QualifiedColumnsRegexpMatcher (children 1)
        Identifier test_table
      TablesInSelectQuery (children 1)
       TablesInSelectQueryElement (children 1)
        TableExpression (children 1)
         TableIdentifier test_table