mysql 存储过程返回更新前记录-CFANZ编程社区

MySQL创建存储过程，实现累加运算，计算 1+2+…+n 等于多少。具体的代码如下

1、实现计算1+2+3+...+n的和

DELIMITER // 
CREATE PROCEDURE sp_add_sum_num(IN n INT) 
BEGIN 
    DECLARE i INT; 
    DECLARE sum INT; 
    SET i = 1; 
    SET sum = 0;
    WHILE i <= n DO 
        SET sum = sum + i; 
        SET i = i +1; 
    END WHILE; 
    SELECT sum; 
END // 
DELIMITER ;

-- 调用存储过程
(root@192.168.80.85)[superdb]> call sp_add_sum_num(100);
+------+
| sum  |
+------+
| 5050 |
+------+
1 row in set (0.03 sec)

Query OK, 0 rows affected (0.03 sec)

(root@192.168.80.85)[superdb]> call sp_add_sum_num(10);
+------+
| sum  |
+------+
|   55 |
+------+
1 row in set (0.00 sec)

Query OK, 0 rows affected (0.01 sec)

2、查看存储过程和函数的创建信息

使用SHOW CREATE语句查看存储过程和函数的创建信息语法结构 SHOW CREATE {PROCEDURE | FUNCTION} 存储过程名或函数名

(root@192.168.80.85)[superdb]> SHOW CREATE PROCEDURE sp_add_sum_num \G;
*************************** 1. row ***************************
           Procedure: sp_add_sum_num
            sql_mode: ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION
    Create Procedure: CREATE DEFINER=`root`@`%` PROCEDURE `sp_add_sum_num`(IN n INT)
BEGIN
    DECLARE i INT;
    DECLARE sum INT;
    SET i = 1;
    SET sum = 0;
    WHILE i <= n DO
        SET sum = sum + i;
        SET i = i +1;
    END WHILE;
    SELECT sum;
END
character_set_client: utf8mb4
collation_connection: utf8mb4_0900_ai_ci
  Database Collation: utf8mb4_0900_ai_ci
1 row in set (0.00 sec)

ERROR:
No query specified

3、查看存储过程和函数的状态信息

(root@192.168.80.85)[superdb]> SHOW PROCEDURE STATUS like 'sp_add_sum_num';
+---------+----------------+-----------+----------+---------+---------------------+---------------------+---------------+---------+----------------------+----------------------+--------------------+
| Db      | Name           | Type      | Language | Definer | Modified            | Created             | Security_type | Comment | character_set_client | collation_connection | Database Collation |
+---------+----------------+-----------+----------+---------+---------------------+---------------------+---------------+---------+----------------------+----------------------+--------------------+
| superdb | sp_add_sum_num | PROCEDURE | SQL      | root@%  | 2023-06-12 20:47:20 | 2023-06-12 20:47:20 | DEFINER       |         | utf8mb4              | utf8mb4_0900_ai_ci   | utf8mb4_0900_ai_ci |
+---------+----------------+-----------+----------+---------+---------------------+---------------------+---------------+---------+----------------------+----------------------+--------------------+
1 row in set (0.09 sec)

(root@192.168.80.85)[superdb]> SHOW PROCEDURE STATUS like 'sp_add_sum_num' \G;
*************************** 1. row ***************************
                  Db: superdb
                Name: sp_add_sum_num
                Type: PROCEDURE
            Language: SQL
             Definer: root@%
            Modified: 2023-06-12 20:47:20
             Created: 2023-06-12 20:47:20
       Security_type: DEFINER
             Comment:
character_set_client: utf8mb4
collation_connection: utf8mb4_0900_ai_ci
  Database Collation: utf8mb4_0900_ai_ci
1 row in set (0.01 sec)

ERROR:
No query specified

4、从infomation_schema.Routines表中查看存储过程和函数的信息

(root@192.168.80.85)[superdb]> SELECT * FROM information_schema.Routines WHERE ROUTINE_NAME='sp_add_sum_num' AND ROUTINE_TYPE = 'PROCEDURE' \G;                                                                                          
*************************** 1. row ***************************
           SPECIFIC_NAME: sp_add_sum_num
         ROUTINE_CATALOG: def
          ROUTINE_SCHEMA: superdb
            ROUTINE_NAME: sp_add_sum_num
            ROUTINE_TYPE: PROCEDURE
               DATA_TYPE:
CHARACTER_MAXIMUM_LENGTH: NULL
  CHARACTER_OCTET_LENGTH: NULL
       NUMERIC_PRECISION: NULL
           NUMERIC_SCALE: NULL
      DATETIME_PRECISION: NULL
      CHARACTER_SET_NAME: NULL
          COLLATION_NAME: NULL
          DTD_IDENTIFIER: NULL
            ROUTINE_BODY: SQL
      ROUTINE_DEFINITION: BEGIN
    DECLARE i INT;
    DECLARE sum INT;
    SET i = 1;
    SET sum = 0;
    WHILE i <= n DO
        SET sum = sum + i;
        SET i = i +1;
    END WHILE;
    SELECT sum;
END
           EXTERNAL_NAME: NULL
       EXTERNAL_LANGUAGE: SQL
         PARAMETER_STYLE: SQL
        IS_DETERMINISTIC: NO
         SQL_DATA_ACCESS: CONTAINS SQL
                SQL_PATH: NULL
           SECURITY_TYPE: DEFINER
                 CREATED: 2023-06-12 20:47:20
            LAST_ALTERED: 2023-06-12 20:47:20
                SQL_MODE: ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION
         ROUTINE_COMMENT:
                 DEFINER: root@%
    CHARACTER_SET_CLIENT: utf8mb4
    COLLATION_CONNECTION: utf8mb4_0900_ai_ci
      DATABASE_COLLATION: utf8mb4_0900_ai_ci
1 row in set (0.01 sec)