SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Identifier test_table.a
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier test_table
   ExpressionList (children 1)
    OrderByElement (children 1)
     Function plus (children 1)
      ExpressionList (children 2)
       Function equals (children 1)
        ExpressionList (children 2)
         Identifier test_table.a
         Identifier test_table.a
       Literal UInt64_1
