REF CURSOR 总结

标签：SYS_REFCURSOR   REF CURSOR   动态游标   ORACLE 动态游标   

示例1：强类型REF游标

DECLARE
TYPE REF_CURSOR IS REF CURSOR RETURN DJ_DJB%ROWTYPE;
------游标仅能打开DJ_DJB表的数据

REF_C REF_CURSOR;
----游标变量

V_DJB DJ_DJB%ROWTYPE;
SELECTION VARCHAR2(1):=(‘&请输入：‘);
BEGIN
  IF SELECTION=‘1‘ THEN
    OPEN REF_C FOR SELECT * FROM DJ_DJB WHERE SLBH LIKE ‘2016%‘ AND ROWNUM<10;
    ELSIF SELECTION=‘2‘ THEN
    OPEN REF_C FOR SELECT * FROM DJ_DJB WHERE SLBH LIKE ‘2017%‘ AND ROWNUM<10;
    END IF;
    LOOP
      FETCH REF_C INTO V_DJB;
      EXIT WHEN REF_C%NOTFOUND;
      DBMS_OUTPUT.ENABLE(BUFFER_SIZE=>NULL);
      DBMS_OUTPUT.PUT_LINE(V_DJB.SLBH||‘,‘||V_DJB.BDCZH);
      END LOOP;
      CLOSE REF_C;
      END;

示例2：弱类型REF游标

DECLARE
TYPE REF_CURSOR IS REF CURSOR;
REF_C REF_CURSOR;

V_V1 VARCHAR2(100);

SELECTION VARCHAR2(1):=(‘&请输入：‘);

BEGIN
  IF SELECTION=‘1‘ THEN
    OPEN REF_C FOR SELECT TO_CHAR(BDCZH) FROM DJ_DJB WHERE SLBH LIKE ‘2016%‘ AND ROWNUM<10;
        -------弱类型游标对目标表没有限制，数据可以使来自任何表

    ELSIF SELECTION=‘2‘ THEN
    OPEN REF_C FOR SELECT TO_CHAR(QLRMC) FROM DJ_QLRGL WHERE SLBH LIKE ‘2017%‘ AND ROWNUM<10 AND QLRLX=‘权利人‘;
            -------弱类型游标对目标表没有限制，数据可以使来自任何表
    END IF;

    LOOP
      FETCH REF_C INTO V_V1;
      EXIT WHEN REF_C%NOTFOUND;
      DBMS_OUTPUT.ENABLE(BUFFER_SIZE=>NULL);
      DBMS_OUTPUT.PUT_LINE(‘输出结果值：‘||V_V1);
      END LOOP;
      CLOSE REF_C;
      END;

示例3：SYS_REFCURSOR

DECLARE

V_DJB DJ_DJB%ROWTYPE;

REF_C SYS_REFCURSOR; ---利用SYS_REFCUSOR 来声明游标变量

SELECTION VARCHAR2(1):=(‘&请输入：‘);
BEGIN
  IF SELECTION=‘1‘ THEN
    OPEN REF_C FOR SELECT * FROM DJ_DJB WHERE SLBH LIKE ‘2016%‘ AND ROWNUM<10;
    ELSIF SELECTION=‘2‘ THEN
    OPEN REF_C FOR SELECT * FROM DJ_DJB WHERE SLBH LIKE ‘2017%‘ AND ROWNUM<11;
    END IF;

 LOOP
   FETCH REF_C INTO V_DJB;
   EXIT WHEN REF_C%NOTFOUND;
   DBMS_OUTPUT.ENABLE(BUFFER_SIZE=>NULL);
   DBMS_OUTPUT.PUT_LINE(V_DJB.SLBH||‘,‘||V_DJB.BDCZH);
   END LOOP;
   CLOSE REF_C;
   END;

示例4：REF 游标作为参数传递

CREATE OR REPLACE PACKAGE EMP_T
IS
TYPE REF_CURSOR IS REF CURSOR RETURN DJ_DJB%ROWTYPE;
PROCEDURE GET_BDCZH(REF_C IN OUT REF_CURSOR,SELECTION VARCHAR2);
PROCEDURE RETURN_C(SELECTION VARCHAR2);

END;

CREATE OR REPLACE PACKAGE BODY EMP_T 
IS
PROCEDURE GET_BDCZH (REF_C IN OUT REF_CURSOR,SELECTION VARCHAR2)
  IS
  BEGIN
    IF SELECTION =1 THEN
      OPEN REF_C FOR SELECT * FROM DJ_DJB WHERE SLBH LIKE ‘2016%‘ AND ROWNUM<10;
      ELSIF SELECTION=2 THEN
      OPEN REF_C FOR SELECT * FROM DJ_DJB WHERE SLBH LIKE ‘2017%‘ AND ROWNUM<10;
      END IF;
      END;

PROCEDURE RETURN_C (SELECTION VARCHAR2)
  IS
  V_1 REF_CURSOR;
  V_DJB dj_djb%ROWTYPE;

  BEGIN
    GET_BDCZH(V_1,SELECTION);
    LOOP
      FETCH V_1 INTO V_DJB;
      EXIT WHEN V_1%NOTFOUND;
      DBMS_OUTPUT.ENABLE(BUFFER_SIZE=>NULL);
      DBMS_OUTPUT.PUT_LINE(V_DJB.SLBH||‘,‘||V_DJB.BDCZH);
      END LOOP;
      CLOSE V_1;
      END;
      END;
---调用
begin
  EMP_T.RETURN_C(1);
  END;

示例5：使用BULK COLLECT INTO.......批量提取数据

DECLARE
TYPE REF_CURSOR IS REF CURSOR;
REF_C REF_CURSOR;

TYPE R_DJB IS TABLE OF DJ_DJB%ROWTYPE INDEX BY BINARY_INTEGER;
V_DJB R_DJB;
SELECTION VARCHAR2(1):=(‘&请输入：‘);

BEGIN
  IF SELECTION=‘1‘ THEN
  OPEN REF_C FOR SELECT * FROM DJ_DJB WHERE SLBH LIKE ‘2016%‘ AND ROWNUM<100;
  ELSIF SELECTION=‘2‘ THEN
  OPEN REF_C FOR SELECT * FROM DJ_DJB WHERE SLBH LIKE ‘2017%‘ AND ROWNUM<100;
  END IF;
  LOOP
    FETCH REF_C BULK COLLECT INTO V_DJB LIMIT 10;
    ---EXIT WHEN REF_C%NOTFOUND;
     DBMS_OUTPUT.ENABLE(BUFFER_SIZE=>NULL);
    ---FOR I IN 1..V_DJB.COUNT LOOP
    FOR I IN V_DJB.FIRST..V_DJB.LAST LOOP
      DBMS_OUTPUT.PUT_LINE(V_DJB(I).SLBH||‘,‘||V_DJB(I).BDCZH||‘I 的值为：‘||I);
      END LOOP;
      DBMS_OUTPUT.PUT_LINE(‘ROWCOUNT的值：‘||REF_C%ROWCOUNT);
      EXIT WHEN REF_C%NOTFOUND;
      END LOOP;
      END;

BY WOLIAHAITO 2018.04.03

REF CURSOR 总结

标签：SYS_REFCURSOR   REF CURSOR   动态游标   ORACLE 动态游标   

原文地址：http://blog.51cto.com/wolihaito/2094209