MySQL AUTO_INCREMENT according to year

Question

Im creating a ticketing system and this is my table structure:

CREATE TABLE tix_sip
(
tktNum INT UNSIGNED NOT NULL,
sipNum INT UNSIGNED AUTO_INCREMENT,
PRIMARY KEY( sipNum ),
FOREIGN KEY(tktNum) REFERENCES Tix (tktNum)
);

what I would like to happen with my sipNum is to be numbered according to year.

Example: 20140001, 20140002, ..20140334, 20140335....

How do I make it change the first 4 digits automatically so everytime next year comes, it will create new\\another set of AUTO_INCREMENT ed numbers

Example: 20150001, 20150002........ 20160001, 20160002..

btw, Im using php code for my program, in case that could help if a solution would be creating a function. Thanks

Answer 1

You can use MySQL Custom AUTO_INCREMENT values as follows: (read the article first)

Create table and trigger:

CREATE TABLE test
(
    id int not null auto_increment primary key,
    year_autonum varchar(20)
);

delimiter //
DROP TRIGGER IF EXISTS custom_autonums_bi//

CREATE TRIGGER custom_autonums_bi BEFORE INSERT ON test
FOR each ROW
BEGIN
   SET NEW.year_autonum = getNextCustomSeq(year(now()),year(now()));
END//

delimiter ;

Insert some values:

insert into test(id) values (null);
insert into test(id) values (null);
insert into test(id) values (null);
...

Select data:

mysql> select * from test;
+----+--------------+
| id | year_autonum |
+----+--------------+
|  1 | 2014-000001  |
|  2 | 2014-000002  |
|  3 | 2014-000003  |
|  4 | 2014-000004  |
|  5 | 2014-000005  |
|  6 | 2014-000006  |
+----+--------------+
6 rows in set (0.00 sec)

You can change the procedure getNextCustomSeq to ommit the slash - sign.