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使用REF CURSOR处理Oracle的结果集
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Oracle提供REF CURSOR,通过该功能可以实现在程序间传递结果集的功能,利用REF CURSOR也可以实现BULK SQL,从而提高SQL性能。

使用scott用户的emp表实现以下测试案例:

SQL> desc emp
Name Null? Type
----------------------------------------- -------- ----------------------------
EMPNO NOT NULL NUMBER(4)
ENAME VARCHAR2(10)
JOB VARCHAR2(9)
MGR NUMBER(4)
HIREDATE DATE
SAL NUMBER(7,2)
COMM NUMBER(7,2)
DEPTNO NUMBER(2)

使用ref cursor获得结果集输出:

SQL> set serveroutput on
SQL> DECLARE
2 TYPE mytable IS TABLE OF emp%ROWTYPE;
3 l_data mytable;
4 l_refc sys_refcursor;
5 BEGIN
6 OPEN l_refc FOR
7 SELECT empno, ename, job, mgr, hiredate, sal, comm, deptno FROM emp;
8
9 FETCH l_refc BULK COLLECT INTO l_data;
10
11 CLOSE l_refc;
12
13 FOR i IN 1 .. l_data.COUNT
14 LOOP
15 DBMS_OUTPUT.put_line ( l_data (i).ename
16 || ' was hired since '
17 || l_data (i).hiredate
18 );
19 END LOOP;
20 END;
21 /
SMITH was hired since 17-DEC-80
ALLEN was hired since 20-FEB-81
WARD was hired since 22-FEB-81
JONES was hired since 02-APR-81
MARTIN was hired since 28-SEP-81
BLAKE was hired since 01-MAY-81
CLARK was hired since 09-JUN-81
SCOTT was hired since 19-APR-87
KING was hired since 17-NOV-81
TURNER was hired since 08-SEP-81
ADAMS was hired since 23-MAY-87
JAMES was hired since 03-DEC-81
FORD was hired since 03-DEC-81
MILLER was hired since 23-JAN-82

PL/SQL procedure successfully completed.

-The End-


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By eygle on 2007-11-06 16:54 | Comments (6) | SQL.PLSQL | 1657 |

6 Comments

ref cursor翻译成中文,是不是叫“引用游标”?

如何以上语句写在packbody之中,1_refc作为返回值返回,那在外部环境中,比如说pro*c中,该如何处理这个返回值,这样吗?
CURSOR mycursor;
call packbody.func() into :mycursor;??????????
接下来可以把mycursor看作一个普通的游标进行fetch操作了吗?

--盖老师,我觉得用循环取的效率有点低
我是这样做的,效率因该能够高点

--利用9i出来的sys_refcursor
create or REPLACE PROCEDURE proc_get(p_rc out sys_refcursor) as
BEGIN
open p_rc for select table_name,tablespace_name,status from user_table_t;
END;
/
VARIABLE p_rc refcursor;
EXEC proc_get(:p_rc);
print;

============
我有加你msn的,回头有空多向您请教。

--盖老师,我觉得用循环取的效率有点低
我是这样做的,效率因该能够高点

--利用9i出来的sys_refcursor
create or REPLACE PROCEDURE proc_get(p_rc out sys_refcursor) as
BEGIN
open p_rc for select table_name,tablespace_name,status from user_table_t;
END;
/
VARIABLE p_rc refcursor;
EXEC proc_get(:p_rc);
print;

============
我有加你msn的,回头有空多向您请教。

--盖老师,我觉得用循环取的效率有点低
我是这样做的,效率因该能够高点

--利用9i出来的sys_refcursor
create or REPLACE PROCEDURE proc_get(p_rc out sys_refcursor) as
BEGIN
open p_rc for select table_name,tablespace_name,status from user_table_t;
END;
/
VARIABLE p_rc refcursor;
EXEC proc_get(:p_rc);
print;

============
我有加你msn的,回头有空多向您请教。

不用refcursor,用cursor也可以实现的啊


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