MySQL 5.5 創建存儲過程和函數
執行CREATE PROCEDURE和CREATE FUNCTION語句需要CREATE ROUTINE權限。
查看neo用戶現有權限
授權
mysql> grant create routine on fire.* to neo;
Query OK, 0 rows affected (0.12 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.02 sec)
創建存儲過程
注意:在命令行縮進時,不要用tab,要使用空格,否則會報下面的錯
DATE INNER MULTILINESTRING SET UNICODE warnings
DATEDIFF INNOBASE MULTILINESTRINGFROMTEXT SHA UNION
DATETIME INNODB MULTILINESTRINGFROMWKB SHA1 UNIQUE
DATE_ADD INOUT MULTIPOINT SHARE UNIQUE_USERS
-> Info;
->
Display all 903 possibilities? (y or n)
執行存儲過程
授權
mysql> grant execute on fire.* to neo;
Query OK, 0 rows affected (0.04 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
也可以直接在Navicat里面執行
編輯存儲過程
調用存儲過程
創建不含參數的存儲過程,和Oracle不同的是,存儲過程名字后面必須要有()
mysql> delimiter $$
mysql> create procedure proc_Subscribers_update()
-> begin
-> DECLARE v_count INT;
-> select ifnull(max(a),0) into v_count from t2;
-> while v_count < 2 do
-> select concat('the maximum value is ',v_count);
-> set v_count = v_count+1;
-> end while;
-> end$$
Query OK, 0 rows affected (0.06 sec)
創建包含傳入參數的存儲過程
delimiter $$
create procedure proc_Subscribers_update(IN v_fetch_cnt INT, IN v_sleep_secs INT)
begin
DECLARE v_count INT;
DECLARE v_times INT DEFAULT 1;
DECLARE v_max_value INT;
/*compute the times that the loop runs*/
select ceil(count(MSISDN))/v_fetch_cnt into v_count from tmp_Subscribers_01;
/*compute the maximum rows that have been already updated*/
WHILE v_times < v_count DO
select ifnull(max(id),0) into v_max_value from tmp_Subscribers_02;
if v_max_value < v_fetch_cnt * v_count then
SET v_times = 1 + floor(v_max_value/v_fetch_cnt);
update Subscribers s,tmp_Subscribers_01 t set s.LastAccessTimeStamp=1420066800
where s.MSISDN=t.MSISDN and t.id > v_max_value and t.id <= v_fetch_cnt * v_times;
/*record the processing rows*/
insert into tmp_Subscribers_02 select id, MSISDN, now() from tmp_Subscribers_01 where id = v_fetch_cnt * v_times;
select concat('The job',' has already updated ', v_fetch_cnt * v_times, ' rows..') as Info;
select sleep(v_sleep_secs);
end if;
commit;
END WHILE;
select concat('The job',' is ','finished!') as Info;
commit;
end$$
刪除存儲過程
需要授予alter routine權限
mysql> grant alter routine on fire.* to neo;
Query OK, 0 rows affected (0.00 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
在mysql客戶端中創建調用存儲過程
MariaDB [test]> delimiter //
MariaDB [test]> create procedure simpleproc(out param1 int)
-> begin
-> select count(*) into param1 from t;
-> end//
Query OK, 0 rows affected (0.12 sec)
MariaDB [test]> delimiter ;
MariaDB [test]> CALL simpleproc(@a);
Query OK, 1 row affected (0.08 sec)
MariaDB [test]> select @a;
+------+
| @a |
+------+
| 1 |
+------+
1 row in set (0.00 sec)
在調用的時候,如果參數不帶@,會報下面的錯
mysql> call proc_test(a,b);
ERROR 1414 (42000): OUT or INOUT argument 1 for routine test.proc_test is not a variable or NEW pseudo-variable in BEFORE trigger
查看存儲過程的狀態
MariaDB [test]> show procedure status like 'simpleproc'\G
*************************** 1. row ***************************
Db: test
Name: simpleproc
Type: PROCEDURE
Definer: root@localhost
Modified: 2016-07-01 08:16:20
Created: 2016-07-01 08:16:20
Security_type: DEFINER
Comment:
character_set_client: utf8
collation_connection: utf8_general_ci
Database Collation: utf8_general_ci
1 row in set (0.00 sec)
通過information_schema的視圖查看存儲過程的相關信息
MariaDB [test]> select * from information_schema.routines where routine_name='simpleproc'\G
*************************** 1. row ***************************
SPECIFIC_NAME: simpleproc
ROUTINE_CATALOG: def
ROUTINE_SCHEMA: test
ROUTINE_NAME: simpleproc
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
select count(*) into param1 from t;
end
EXTERNAL_NAME: NULL
EXTERNAL_LANGUAGE: NULL
PARAMETER_STYLE: SQL
IS_DETERMINISTIC: NO
SQL_DATA_ACCESS: CONTAINS SQL
SQL_PATH: NULL
SECURITY_TYPE: DEFINER
CREATED: 2016-07-01 08:16:20
LAST_ALTERED: 2016-07-01 08:16:20
SQL_MODE: NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
ROUTINE_COMMENT:
DEFINER: root@localhost
CHARACTER_SET_CLIENT: utf8
COLLATION_CONNECTION: utf8_general_ci
DATABASE_COLLATION: utf8_general_ci
1 row in set (0.00 sec)
查看存儲過程的定義
MariaDB [test]> show create procedure simpleproc\G
*************************** 1. row ***************************
Procedure: simpleproc
sql_mode: NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
Create Procedure: CREATE DEFINER=`root`@`localhost` PROCEDURE `simpleproc`(out param1 int)
begin
select count(*) into param1 from t;
end
character_set_client: utf8
collation_connection: utf8_general_ci
Database Collation: utf8_general_ci
1 row in set (0.00 sec)
創建函數
MySQL的傳入參數不能設置默認值,否則會報錯
mysql> delimiter $$
mysql> CREATE FUNCTION format_selectQuery (THE_TABLE_NAME VARCHAR(75), THE_COLUMNS_NAME VARCHAR(75), THE_CONDITION VARCHAR(75) DEFAULT NULL) RETURNS VARCHAR(200) DETERMINISTIC
-> BEGIN
-> /*SELECT concat(' WHERE ', THE_CONDITION) INTO @WHERE_CLAUSE;
/*> IF THE_CONDITION IS NULL THEN
/*> SET @WHERE_CLAUSE = NULL;
/*> END IF;
/*> RETURN concat('SELECT ', THE_COLUMNS_NAME, ' FROM ', THE_TABLE_NAME, @WHERE_CLAUSE);*/
-> RETURN 1;
-> END $$
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DEFAULT '') RETURNS VARCHAR(200) DETERMINISTIC
BEGIN
RETURN 1;
END' at line 1
mysql> delimiter ;
需要注意的是,在MySQL里,創建函數中在函數聲明后面的返回關鍵字是RETURNS
執行函數
需要注意的是,函數或存儲過程里面的參數聲明順序,順序有誤,容易引起語法報錯
delimiter $$
CREATE FUNCTION is_ChangeDescColumnExist (THE_VERSION_LEVEL_TABLE_NAME VARCHAR(35)) RETURNS INT DETERMINISTIC
BEGIN
/* 聲明變量 */
DECLARE nbr INT;
/* 聲明異常 */
DECLARE CONTINUE HANDLER FOR NOT FOUND set nbr = 1;
/* 給變量賦值 */
SET nbr =0;
select count(*) into nbr from information_schema.columns where table_name = THE_VERSION_LEVEL_TABLE_NAME and
(column_name ='C_CHANGE_DESCRIPTION');
IF nbr = 1 THEN
RETURN 1;
ELSE
RETURN 0;
END IF;
END$$
delimiter ;
將上面的順序放置錯誤,則會引起報錯
mysql> CREATE FUNCTION is_ChangeDescColumnExist (THE_VERSION_LEVEL_TABLE_NAME VARCHAR(35)) RETURNS INT DETERMINISTIC
-> BEGIN
-> DECLARE nbr INT;
-> SET nbr =0;
-> DECLARE CONTINUE HANDLER FOR NOT FOUND set nbr = 10;
->
-> select count(*) into nbr from information_schema.columns where table_name = THE_VERSION_LEVEL_TABLE_NAME and
-> (column_name ='C_CHANGE_DESCRIPTION');
-> IF nbr = 1 THEN
-> RETURN 1;
-> ELSE
ELSE ELSEIF
-> ELSE
-> RETURN 0;
-> END IF;
-> END$$
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DECLARE CONTINUE HANDLER FOR NOT FOUND set nbr = 10;
select c' at line 5
創建兩個函數,返回兩種變量,一種是DECLARE變量,一種是@變量
delimiter $$
CREATE FUNCTION is_TableMigrated (THE_VERSION_LEVEL_TABLE_NAME VARCHAR(20)) RETURNS INTEGER DETERMINISTIC
BEGIN
DECLARE nbr integer;
SET nbr =222;
RETURN nbr;
END$$
delimiter ;
delimiter $$
CREATE FUNCTION is_TableMigrated (THE_VERSION_LEVEL_TABLE_NAME VARCHAR(20)) RETURNS INTEGER DETERMINISTIC
BEGIN
DECLARE nbr integer;
SET @nbr2 =22222;
RETURN @nbr2;
END$$
delimiter ;