oracle - 有条件地定义一个游标

Question

我在 Oracle 中有一个过程，它需要一个 varchar2参数。根据该参数的值，我需要定义一个游标。游标将根据参数的值对不同的表进行操作。

我想做类似下面的事情，但它在 CURSOR 中抛出了一个错误定义一段代码。有任何想法吗？

PROCEDURE GET_RECORDS(v_action IN VARCHAR2)
IS
CURSOR get_records
IS
       IF(v_action = 'DO THIS') THEN
           SELECT * from <THIS>;
       ELSE
           SELECT * from <THAT>;
       END IF;
BEGIN
       OPEN get_records;

       FETCH get_records
       INTO v_thing;

       v_loop := 0;
       WHILE get_records%FOUND
       LOOP

           FETCH get_records
           INTO v_thing;

       END LOOP;
       CLOSE get_records;
END;

Answer 1

您将需要一个 REF CURSOR 并有条件地打开它，例如:

SQL> CREATE OR REPLACE PROCEDURE GET_RECORDS(v_action IN VARCHAR2) IS
  2     v_thing     VARCHAR2(10);
  3     get_records SYS_REFCURSOR;
  4  BEGIN
  5     IF (v_action = 'DO THIS') THEN
  6        OPEN get_records FOR
  7           SELECT 1 FROM dual;
  8     ELSE
  9        OPEN get_records FOR
 10           SELECT 2 FROM dual;
 11     END IF;
 12  
 13     LOOP
 14        FETCH get_records INTO v_thing;
 15        EXIT WHEN get_records%NOTFOUND;
 16        /* do things */
 17        dbms_output.put_line(v_thing);
 18     END LOOP;
 19     CLOSE get_records;
 20  END;
 21  /

Procedure created

SQL> exec get_records ('DO THIS');
1

PL/SQL procedure successfully completed

SQL> exec get_records ('DO THAT');
2

PL/SQL procedure successfully completed