MySQL Tutorial/Procedure Function/Repeat until
REPEAT Statement
To loop over a set of statements until a post-statement condition is met, use the REPEAT statement.
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[begin_label:] REPEAT
statement_list
UNTIL search_condition END REPEAT [end_label]</source>
Repeat until loop
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mysql> mysql> delimiter // mysql> create procedure test_repeat (IN in_count INT)
-> BEGIN -> declare count INT default 0; -> -> increment: repeat -> set count = count + 1; -> select count; -> until count > 10 -> end repeat increment; -> -> END -> //
Query OK, 0 rows affected (0.00 sec) mysql> mysql> delimiter ; mysql> mysql> call test_repeat(10); +-------+ | count | +-------+ | 1 | +-------+ 1 row in set (0.00 sec) +-------+ | count | +-------+ | 2 | +-------+ 1 row in set (0.00 sec) +-------+ | count | +-------+ | 3 | +-------+ 1 row in set (0.01 sec) +-------+ | count | +-------+ | 4 | +-------+ 1 row in set (0.01 sec) +-------+ | count | +-------+ | 5 | +-------+ 1 row in set (0.01 sec) +-------+ | count | +-------+ | 6 | +-------+ 1 row in set (0.01 sec) +-------+ | count | +-------+ | 7 | +-------+ 1 row in set (0.01 sec) +-------+ | count | +-------+ | 8 | +-------+ 1 row in set (0.01 sec) +-------+ | count | +-------+ | 9 | +-------+ 1 row in set (0.01 sec) +-------+ | count | +-------+ | 10 | +-------+ 1 row in set (0.01 sec) +-------+ | count | +-------+ | 11 | +-------+ 1 row in set (0.01 sec) Query OK, 0 rows affected (0.01 sec) mysql> mysql> drop procedure test_repeat; Query OK, 0 rows affected (0.00 sec)</source>
Using Repeat ... until to loop through a cursor
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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 (0.00 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 $$ mysql> CREATE PROCEDURE myProc (in_customer_id INT)
-> BEGIN -> -> DECLARE l_first_name VARCHAR(30); -> DECLARE l_id INT; -> DECLARE l_city VARCHAR(30); -> DECLARE l_department_count INT; -> DECLARE no_more_departments INT; -> -> DECLARE dept_csr CURSOR FOR -> SELECT id,first_name, city -> FROM employee; -> -> DECLARE CONTINUE HANDLER FOR NOT FOUND SET no_more_departments=1; -> -> SET no_more_departments=0; -> OPEN dept_csr; -> dept_loop:REPEAT -> FETCH dept_csr INTO l_id,l_first_name,l_city; -> IF no_more_departments=0 THEN -> SET l_department_count=l_department_count+1; -> END IF; -> select l_id,l_first_name,l_city; -> UNTIL no_more_departments -> END REPEAT dept_loop; -> CLOSE dept_csr; -> SET no_more_departments=0; -> -> -> END$$
Query OK, 0 rows affected (0.00 sec) mysql> delimiter ; mysql> mysql> call myProc(1); +------+--------------+---------+ | l_id | l_first_name | l_city | +------+--------------+---------+ | 1 | Jason | Toronto | +------+--------------+---------+ 1 row in set (0.02 sec) +------+--------------+-----------+ | l_id | l_first_name | l_city | +------+--------------+-----------+ | 2 | Alison | Vancouver | +------+--------------+-----------+ 1 row in set (0.02 sec) +------+--------------+-----------+ | l_id | l_first_name | l_city | +------+--------------+-----------+ | 3 | James | Vancouver | +------+--------------+-----------+ 1 row in set (0.02 sec) +------+--------------+-----------+ | l_id | l_first_name | l_city | +------+--------------+-----------+ | 4 | Celia | Vancouver | +------+--------------+-----------+ 1 row in set (0.02 sec) +------+--------------+-----------+ | l_id | l_first_name | l_city | +------+--------------+-----------+ | 5 | Robert | Vancouver | +------+--------------+-----------+ 1 row in set (0.02 sec) +------+--------------+----------+ | l_id | l_first_name | l_city | +------+--------------+----------+ | 6 | Linda | New York | +------+--------------+----------+ 1 row in set (0.02 sec) +------+--------------+----------+ | l_id | l_first_name | l_city | +------+--------------+----------+ | 7 | David | New York | +------+--------------+----------+ 1 row in set (0.03 sec) +------+--------------+-----------+ | l_id | l_first_name | l_city | +------+--------------+-----------+ | 8 | James | Vancouver | +------+--------------+-----------+ 1 row in set (0.03 sec) +------+--------------+-----------+ | l_id | l_first_name | l_city | +------+--------------+-----------+ | 8 | James | Vancouver | +------+--------------+-----------+ 1 row in set (0.38 sec) Query OK, 0 rows affected (0.38 sec) mysql> drop procedure myProc; Query OK, 0 rows affected (0.02 sec) mysql> mysql> mysql> mysql> drop table Employee; Query OK, 0 rows affected (0.00 sec)</source>