这是我编写的程序- Cursors c1
& c2
。c2
在里面c1
,我尝试在c2
下面声明c1
(在c1
光标外),但I
没有采用更新的值:(任何让它工作的建议都会有帮助,谢谢
create table t1(i int);
create table t2(i int, j int);
insert into t1(i) values(1), (2), (3), (4), (5);
insert into t2(i, j) values(1, 6), (2, 7), (3, 8), (4, 9), (5, 10);
delimiter $
CREATE PROCEDURE p1()
BEGIN
DECLARE I INT;
DECLARE J INT;
DECLARE done INT DEFAULT 0;
DECLARE c1 CURSOR FOR SELECT i FROM t1;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1;
OPEN c1;
REPEAT
FETCH c1 INTO I;
IF NOT done THEN
select I;
DECLARE c2 CURSOR FOR
SELECT j FROM t2 WHERE i = I;
OPEN c2;
REPEAT
FETCH c2 into J;
IF NOT done THEN
SELECT J;
END IF;
UNTIL done END REPEAT;
CLOSE c2;
set done = 0;
END IF;
UNTIL done END REPEAT;
CLOSE c1;
END$
delimiter ;