看一看all_coll_types
視圖。 Char_used
柱,它告訴你是否varchar2
元件的長度以字節或字符指定只存在有:
SQL> create type t_coll_type is table of varchar2(10 byte);
2/
Type created
SQL>
SQL> select type_name
2 , elem_type_name
3 , char_used
4 from all_coll_types
5 where type_name = 'T_COLL_TYPE'
6 ;
TYPE_NAME ELEM_TYPE_NAME CHAR_USED
------------------------------ ------------------------------ ---------
T_COLL_TYPE VARCHAR2 B
SQL> create type t_coll_type2 is table of varchar2(10 char);
2/
Type created
SQL>
SQL> select type_name
2 , elem_type_name
3 , char_used
4 from all_coll_types
5 where type_name = 'T_COLL_TYPE2'
6 ;
TYPE_NAME ELEM_TYPE_NAME CHAR_USED
------------------------------ ------------------------------ ---------
T_COLL_TYPE2 VARCHAR2 C
哇,不同結構對用戶_ *和ALL_ *圖。我一直認爲它們是相同的 – turbanoff