有关光标的问题 !求助!!!
mysql> create table payment(staff_id int not null ,
     ->                  amount int not null);                        //建表
Query OK, 0 rows affected (1.68 sec)
mysql> INSERT INTO PAYMENT VALUES(1,213);                             //插值
Query OK, 1 row affected (0.08 sec)
mysql> INSERT INTO PAYMENT VALUES(2,213.2312);
Query OK, 1 row affected (0.03 sec)
mysql> INSERT INTO PAYMENT VALUES(3,12);
Query OK, 1 row affected (0.06 sec)
mysql> INSERT INTO PAYMENT VALUES(4,11);
Query OK, 1 row affected (0.03 sec)
mysql> INSERT INTO PAYMENT VALUES(5,21);
Query OK, 1 row affected (0.03 sec)
mysql> INSERT INTO PAYMENT VALUES(6,31);
Query OK, 1 row affected (0.03 sec)
mysql> DELIMITER !!                                            //建立过程PAYMENT_STAT
mysql>  
mysql>                                               //使不同的staff_id值的amount累加mysql> CREATE PROCEDURE PAYMENT_STAT()
     -> BEGIN
     ->  DECLARE I_STAFF_ID INT;
     ->  DECLARE D_AMOUNT DECIMAL(5,2);
     -> DECLARE CUR_PAYMENT CURSOR FOR SELECT STAFF_ID,AMOUNT FROM PAYMEN
     ->  DECLARE EXIT HANDLER FOR NOT FOUND CLOSE CUR_PAYMENT;
     ->
     -> SET @X1=0;
     -> SET @X2=0;
     ->
     -> OPEN CUR_PAYMENT ;
     ->
     -> OPEN CUR_PAYMENT ;
     ->
     -> REPEAT
     ->  FETCH CUR_PAYMENT INTO I_STAFF_ID ,D_AMOUNT ;
     ->          IF I_STAFF_ID =2 THEN
     ->          SET @X1=@X1+D_AMOUNT ;
     ->          ELSE
     ->          SET @X2=@X2+D_AMOUNT ;
     ->          END IF;
     -> UNTIL 0 END REPEAT ;
     -> CLOSE CUR_PAYMENT ;
     ->
     -> END;
     -> !!
Query OK, 0 rows affected (0.42 sec)
mysql> DELIMITER ;
mysql> CALL PAYMENT_STAT();
ERROR 1325 (24000): Cursor is already open     、//为什么会这样呢
mysql> SELECT @X1,@X2;                                               也没有结果输出+------+------+
| @X1  | @X2  |
+------+------+
|    0 |    0 |
+------+------+
1 row in set (0.08 sec)
------解决方案--------------------RROR 1325 (24000): Cursor is already open 、//为什么会这样呢
翻译成中文,游标已经打开。
-> OPEN CUR_PAYMENT ;
 ->
 -> OPEN CUR_PAYMENT ;
你不是打开了两次?
------解决方案--------------------是的,你打开了两次游标。