实际项目当中经常需要在一个存储过程中调用另一个存储过程返回的游标,本文列举了两种情况讲述具体的操作方法。
第一种情况是返回的游标是某个具体的表或视图的数据,如:SQL-Code:
代码如下:
CREATE OR REPLACE PROCEDURE P_TESTA (
PRESULT OUT SYS_REFCURSOR
)
AS
BEGIN
OPEN PRESULT FOR SELECT * FROM USERS;
END P_TESTA;
其中USERS就是数据库中一个表。在调用的时候只要声明一个该表的ROWTYPE类型就可以了:
SQL-Code:
代码如下:
CREATE OR REPLACE PROCEDURE P_TESTB
AS
VARCURSOR SYS_REFCURSOR;
R USERS%ROWTYPE;
BEGIN
P_TESTA(VARCURSOR);
LOOP
FETCH VARCURSOR INTO R;
EXIT WHEN VARCURSOR%NOTFOUND;
DBMS_OUTPUT.PUT_LINE(R.NAME);
END LOOP;
END P_TESTB;
第二种情况,我们返回的不是表的所有的列,或许只是其中一列或两列,如:
SQL-Code:
代码如下:
CREATE OR REPLACE PROCEDURE P_TESTA (
PRESULT OUT SYS_REFCURSOR
)
AS
BEGIN
OPEN PRESULT FOR SELECT ID,NAME FROM USERS;
END P_TESTA;
这里我们只返回了USERS表的ID,NAME这两个列,那么调用的时候也必须做相应的修改:
SQL-Code:
代码如下:
CREATE OR REPLACE PROCEDURE P_TESTB
AS
VARCURSOR SYS_REFCURSOR;
CURSOR TMPCURSOR IS SELECT ID,NAME FROM USERS WHERE ROWNUM=1;
R TMPCURSOR%ROWTYPE;
BEGIN
P_TESTA(VARCURSOR);
LOOP
FETCH VARCURSOR INTO R;
EXIT WHEN VARCURSOR%NOTFOUND;
DBMS_OUTPUT.PUT_LINE(R.ID);
END LOOP;
END P_TESTB;
与之前不同的是我们声明了一个游标类型的变量TMPCURSOR ,注意TMPCURSOR 的结构必须与存储过程P_TESTA 返回的游标结构一致,否则就会出现错误。同理只要保持两个游标类型结构一致,就可以实现自由调用。

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