mysql存储过程循环 while/repeat/loop

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先把语句结束符设置成//

mysql> DELIMITER // 

1. while 条件 do … end while

mysql> create procedure proce_while()
    -> begin
    -> declare count int;
    -> set count = 0;
    -> while count < 5 do
    -> insert into onecolumn values(count);
    -> set count = count + 1;
    -> end while;
    -> end//

然后执行

mysql> call proce_while()//                                                                                
Query OK, 1 row affected (0.01 sec)

mysql> select * from onecolumn//
+----+
| id |
+----+
|  0 |
|  1 |
|  2 |
|  3 |
|  4 |
+----+
5 rows in set (0.00 sec)

2. repeat xxx until 条件 end repeat
   创建存储过程

mysql> create procedure proce_repeat()
    -> begin
    -> declare
    -> count int;
    -> set count = 10;
    -> repeat
    -> insert into onecolumn values(count);
    -> set count = count + 1;
    -> until count >=15 end repeat;
    -> end
    -> //
Query OK, 0 rows affected (0.00 sec)

执行存储过程

mysql> call proce_repeat()//
ERROR 1062 (23000): Duplicate entry '10' for key 'PRIMARY'
mysql> call proce_repeat()//
Query OK, 1 row affected (0.03 sec)

mysql> select * from onecolumn where id >=10//
+----+
| id |
+----+
| 10 |
| 11 |
| 12 |
| 13 |
| 14 |
+----+
5 rows in set (0.00 sec)

3. loop_label:loop … leave loop_lable … end loop
   创建存储过程

mysql> create procedure proce_loop()
    -> begin
    -> declare count int;
    -> set count = 20;
    -> loop_lable:loop
    -> insert into onecolumn values(count);
    -> set count = count + 1;
    -> if(count >=25) then 
    -> leave loop_lable;
    -> end if;
    -> end loop;
    -> end//

执行存储过程：

call proce_loop()//
Query OK, 1 row affected (0.03 sec)

mysql> select * from onecolumn where id >=20//
+----+
| id |
+----+
| 20 |
| 21 |
| 22 |
| 23 |
| 24 |
+----+
5 rows in set (0.00 sec)