SQL/MySQL/Procedure Function/Procedure
Содержание
Calling a Single-Statement Procedure
mysql>
mysql>
mysql> CREATE TABLE Employee(
-> id int,
-> first_name VARCHAR(15),
-> last_name VARCHAR(15),
-> start_date DATE,
-> end_date DATE,
-> salary FLOAT(8,2),
-> city VARCHAR(10),
-> description VARCHAR(15)
-> );
Query OK, 0 rows affected (0.08 sec)
mysql>
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values (1,"Jason", "Martin", "19960725", "20060725", 1234.56, "Toronto", "Programmer");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(2,"Alison", "Mathews", "19760321", "19860221", 6661.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(3,"James", "Smith", "19781212", "19900315", 6544.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(4,"Celia", "Rice", "19821024", "19990421", 2344.78, "Vancouver","Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(5,"Robert", "Black", "19840115", "19980808", 2334.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(6,"Linda", "Green", "19870730", "19960104", 4322.78,"New York", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(7,"David", "Larry", "19901231", "19980212", 7897.78,"New York", "Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(8,"James", "Cat", "19960917", "20020415", 1232.78,"Vancouver", "Tester");
Query OK, 1 row affected (0.02 sec)
mysql>
mysql> select * from Employee;
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| id | first_name | last_name | start_date | end_date | salary | city | description |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| 1 | Jason | Martin | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto | Programmer |
| 2 | Alison | Mathews | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester |
| 3 | James | Smith | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester |
| 4 | Celia | Rice | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager |
| 5 | Robert | Black | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester |
| 6 | Linda | Green | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester |
| 7 | David | Larry | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager |
| 8 | James | Cat | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
8 rows in set (0.00 sec)
mysql>
mysql>
mysql>
mysql> create procedure myProc ()
-> SELECT id,first_name FROM employee;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql> call myProc ();
+------+------------+
| id | first_name |
+------+------------+
| 1 | Jason |
| 2 | Alison |
| 3 | James |
| 4 | Celia |
| 5 | Robert |
| 6 | Linda |
| 7 | David |
| 8 | James |
+------+------------+
8 rows in set (0.00 sec)
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql> drop procedure myProc;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
mysql> drop table Employee;
Query OK, 0 rows affected (0.00 sec)
Creating a Multistatement Stored Procedure
mysql>
mysql>
mysql> CREATE TABLE Employee(
-> id int,
-> first_name VARCHAR(15),
-> last_name VARCHAR(15),
-> start_date DATE,
-> end_date DATE,
-> salary FLOAT(8,2),
-> city VARCHAR(10),
-> description VARCHAR(15)
-> );
Query OK, 0 rows affected (0.03 sec)
mysql>
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values (1,"Jason", "Martin", "19960725", "20060725", 1234.56, "Toronto", "Programmer");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(2,"Alison", "Mathews", "19760321", "19860221", 6661.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(3,"James", "Smith", "19781212", "19900315", 6544.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(4,"Celia", "Rice", "19821024", "19990421", 2344.78, "Vancouver","Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(5,"Robert", "Black", "19840115", "19980808", 2334.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(6,"Linda", "Green", "19870730", "19960104", 4322.78,"New York", "Tester");
Query OK, 1 row affected (0.01 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(7,"David", "Larry", "19901231", "19980212", 7897.78,"New York", "Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(8,"James", "Cat", "19960917", "20020415", 1232.78,"Vancouver", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> select * from Employee;
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| id | first_name | last_name | start_date | end_date | salary | city | description |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| 1 | Jason | Martin | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto | Programmer |
| 2 | Alison | Mathews | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester |
| 3 | James | Smith | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester |
| 4 | Celia | Rice | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager |
| 5 | Robert | Black | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester |
| 6 | Linda | Green | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester |
| 7 | David | Larry | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager |
| 8 | James | Cat | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
8 rows in set (0.00 sec)
mysql>
mysql>
mysql>
mysql> DELIMITER //
mysql> CREATE PROCEDURE merge_employee (IN old_id INT, IN new_id INT, OUT error VARCHAR(100))
-> SQL SECURITY DEFINER
-> COMMENT "This is the comment"
-> BEGIN
-> DECLARE old_count INT DEFAULT 0;
-> DECLARE new_count INT DEFAULT 0;
-> DECLARE addresses_changed INT DEFAULT 0;
->
-> ## check to make sure the old_id and new_id exists
-> SELECT count(*) INTO old_count FROM employee WHERE id = old_id;
-> SELECT count(*) INTO new_count FROM employee WHERE id = new_id;
->
-> IF !old_count THEN
-> SET error = "old id does not exist";
-> ELSEIF !new_count THEN
-> SET error = "new id does not exist";
-> ELSE
-> UPDATE employee SET id = new_id WHERE id = old_id;
-> SELECT row_count() INTO addresses_changed;
->
-> DELETE FROM employee WHERE id = old_id;
->
-> SELECT addresses_changed;
->
-> END IF;
-> END
-> //
Query OK, 0 rows affected (0.00 sec)
mysql> DELIMITER ;
mysql>
mysql>
mysql> call merge_employee (1,4,@error);
+-------------------+
| addresses_changed |
+-------------------+
| 1 |
+-------------------+
1 row in set (0.00 sec)
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql> select @error;
+--------+
| @error |
+--------+
| NULL |
+--------+
1 row in set (0.00 sec)
mysql>
mysql> drop procedure merge_employee;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
mysql>
mysql>
mysql> drop table Employee;
Query OK, 0 rows affected (0.00 sec)
Creating a Single-Statement Procedure
mysql>
mysql>
mysql> create procedure myProc ()
-> SELECT id,first_name FROM employee;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql> call myProc ();
mysql>
mysql> drop procedure myProc;
Query OK, 0 rows affected (0.00 sec)
The ALTER statement lets you change the characteristics of a stored procedure
mysql>
mysql> DELIMITER //
mysql> CREATE PROCEDURE myProc (IN in_count INT)
-> BEGIN
-> DECLARE count INT default 0;
->
-> increment: LOOP
-> SET count = count + 1;
-> IF count < 20 THEN ITERATE increment; END IF;
-> IF count > in_count THEN LEAVE increment;
-> END IF;
-> END LOOP increment;
->
-> SELECT count;
-> END
-> //
Query OK, 0 rows affected (0.00 sec)
mysql> DELIMITER ;
mysql>
mysql> call myProc(5);
+-------+
| count |
+-------+
| 20 |
+-------+
1 row in set (0.02 sec)
Query OK, 0 rows affected (0.02 sec)
mysql>
mysql>
mysql> ALTER PROCEDURE myProc SQL SECURITY INVOKER
-> COMMENT "This is my procedure";
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
mysql> SELECT * FROM mysql.proc WHERE name = "myProc"\G
*************************** 1. row ***************************
db: test
name: myProc
type: PROCEDURE
specific_name: myProc
language: SQL
sql_data_access: CONTAINS_SQL
is_deterministic: NO
security_type: INVOKER
param_list: IN in_count INT
returns:
body: BEGIN
DECLARE count INT default 0;
increment: LOOP
SET count = count + 1;
IF count < 20 THEN ITERATE increment; END IF;
IF count > in_count THEN LEAVE increment;
END IF;
END LOOP increment;
SELECT count;
END
definer: root@localhost
created: 2007-07-23 18:58:35
modified: 2007-07-23 18:58:35
sql_mode:
comment: This is my procedure
1 row in set (0.00 sec)
mysql>
mysql> drop procedure myProc;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
To remove a stored procedures, use the DROP statement
mysql>
mysql>
mysql>
mysql> DELIMITER //
mysql> CREATE PROCEDURE myProc (IN in_count INT)
-> BEGIN
-> DECLARE count INT default 0;
->
-> increment: LOOP
-> SET count = count + 1;
-> IF count < 20 THEN ITERATE increment; END IF;
-> IF count > in_count THEN LEAVE increment;
-> END IF;
-> END LOOP increment;
->
-> SELECT count;
-> END
-> //
Query OK, 0 rows affected (0.00 sec)
mysql> DELIMITER ;
mysql>
mysql> call myProc(5);
+-------+
| count |
+-------+
| 20 |
+-------+
1 row in set (0.00 sec)
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
mysql> drop procedure test.myProc;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
mysql>
Using an OUT parameter
mysql>
mysql>
mysql>
mysql> CREATE TABLE Employee(
-> id int,
-> first_name VARCHAR(15),
-> last_name VARCHAR(15),
-> start_date DATE,
-> end_date DATE,
-> salary FLOAT(8,2),
-> city VARCHAR(10),
-> description VARCHAR(15)
-> );
Query OK, 0 rows affected (0.02 sec)
mysql>
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values (1,"Jason", "Martin", "19960725", "20060725", 1234.56, "Toronto", "Programmer");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(2,"Alison", "Mathews", "19760321", "19860221", 6661.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(3,"James", "Smith", "19781212", "19900315", 6544.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(4,"Celia", "Rice", "19821024", "19990421", 2344.78, "Vancouver","Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(5,"Robert", "Black", "19840115", "19980808", 2334.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(6,"Linda", "Green", "19870730", "19960104", 4322.78,"New York", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(7,"David", "Larry", "19901231", "19980212", 7897.78,"New York", "Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(8,"James", "Cat", "19960917", "20020415", 1232.78,"Vancouver", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> select * from Employee;
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| id | first_name | last_name | start_date | end_date | salary | city | description |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| 1 | Jason | Martin | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto | Programmer |
| 2 | Alison | Mathews | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester |
| 3 | James | Smith | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester |
| 4 | Celia | Rice | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager |
| 5 | Robert | Black | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester |
| 6 | Linda | Green | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester |
| 7 | David | Larry | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager |
| 8 | James | Cat | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
8 rows in set (0.00 sec)
mysql>
mysql>
mysql>
mysql>
mysql> delimiter //
mysql>
mysql> CREATE PROCEDURE simpleproc (OUT param1 INT)
-> BEGIN
-> SELECT COUNT(*) INTO param1 FROM employee;
-> END;
-> //
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql> delimiter ;
mysql>
mysql> CALL simpleproc(@a);
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql> SELECT @a;
+------+
| @a |
+------+
| 8 |
+------+
1 row in set (0.00 sec)
mysql>
mysql> drop procedure simpleproc;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
mysql> drop table Employee;
Query OK, 0 rows affected (0.00 sec)
mysql>