DBMS_OUTPUT

功能描述

DBMS_OUTPUT内置包用于提供在存储过程或包内对外发送信息的功能，该内置包包含以下子程序：

• serveroutput 为on 时允许将dbms_output.put_line的输出信息输出至vsql的命令界面的屏幕上。使用以下语句设置参数：

  SET serveroutput =on;
  

• serveroutput默认值是off 可以通过配置.psqlrc文件设置缺省值。

注意事项

该功能仅在数据库兼容模式为Oracle时支持（即数据库实例初始化时指定DBCOMPATIBILITY='A'）。

示例

1、设置serveroutput为on。

SET serveroutput =on;

2、创建测试表并插入数据。

CREATE TABLE emp (
 empno NUMBER(4) ,
 ename VARCHAR2(10),
 job VARCHAR2(9),
 mgr NUMBER(4),
 hiredate DATE,
 sal NUMBER(7,2) CONSTRAINT emp_sal_ck CHECK (sal > 0),
 comm NUMBER(7,2));
INSERT INTO emp VALUES (7369,'SMITH','CLERK',7902,'17-DEC-80',800,NULL);
INSERT INTO emp VALUES (7499,'ALLEN','SALESMAN',7698,'20-FEB-81',1600,300);
INSERT INTO emp VALUES (7521,'WARD','SALESMAN',7698,'22-FEB-81',1250,500);
INSERT INTO emp VALUES (7566,'JONES','MANAGER',7839,'02-APR-81',2975,NULL);
INSERT INTO emp VALUES (7654,'MARTIN','SALESMAN',7698,'28-SEP-81',1250,1400);
INSERT INTO emp VALUES (7698,'BLAKE','MANAGER',7839,'01-MAY-81',2850,NULL);
INSERT INTO emp VALUES (7782,'CLARK','MANAGER',7839,'09-JUN-81',2450,NULL);
INSERT INTO emp VALUES (7788,'SCOTT','ANALYST',7566,'19-APR-87',3000,NULL);
INSERT INTO emp VALUES (7839,'KING','PRESIDENT',NULL,'17-NOV-81',5000,NULL);
INSERT INTO emp VALUES (7844,'TURNER','SALESMAN',7698,'08-SEP-81',1500,0);
INSERT INTO emp VALUES (7876,'ADAMS','CLERK',7788,'23-MAY-87',1100,NULL);
INSERT INTO emp VALUES (7900,'JAMES','CLERK',7698,'03-DEC-81',950,NULL);
INSERT INTO emp VALUES (7902,'FORD','ANALYST',7566,'03-DEC-81',3000,NULL);
INSERT INTO emp VALUES (7934,'MILLER','CLERK',7782,'23-JAN-82',1300,NULL);

3、创建并调用存储过程。

CREATE OR REPLACE PROCEDURE list_emp()
 IS
 v_empno NUMBER(4);
 v_ename VARCHAR2(10);
 cursor emp_cur  is  SELECT empno, ename FROM emp ORDER BY empno;
BEGIN
 OPEN emp_cur;
 DBMS_OUTPUT.PUT_LINE('EMPNO ENAME');
 DBMS_OUTPUT.PUT_LINE('----- -------');
 LOOP
 FETCH emp_cur INTO v_empno, v_ename;
 EXIT WHEN emp_cur%NOTFOUND;
 DBMS_OUTPUT.PUT_LINE(v_empno || ' ' || v_ename);
 END LOOP;
 CLOSE emp_cur;
END;
/

call list_emp();

返回结果为：

EMPNO ENAME
----- -------
7369 SMITH
7499 ALLEN
7521 WARD
7566 JONES
7654 MARTIN
7698 BLAKE
7782 CLARK
7788 SCOTT
7839 KING
7844 TURNER
7876 ADAMS
7900 JAMES
7902 FORD
7934 MILLER
 list_emp
----------

(1 row)