Question

I have solution where i need that id in one table starts every month from 1. I’m thinking of using month name as primary key together with id auto incerement. Am I wrong way? Does someone have any idea?

Answer 1

Example with MYISAM table:

CREATE TABLE table1(
  yearmonth_id INT(11) NOT NULL, -- combination of year and month
  id INT(11) NOT NULL AUTO_INCREMENT,
  PRIMARY KEY (yearmonth_id, id)
)
ENGINE = MYISAM;

INSERT INTO table1 VALUES(201110, NULL);
INSERT INTO table1 VALUES(201110, NULL);
INSERT INTO table1 VALUES(201110, NULL);

INSERT INTO table1 VALUES(201112, NULL);
INSERT INTO table1 VALUES(201112, NULL);
INSERT INTO table1 VALUES(201112, NULL);

INSERT INTO table1 VALUES(201201, NULL);
INSERT INTO table1 VALUES(201201, NULL);
INSERT INTO table1 VALUES(201201, NULL);

SELECT * FROM table1;
+--------------+----+
| yearmonth_id | id |
+--------------+----+
|       201110 |  1 |
|       201110 |  2 |
|       201110 |  3 |
|       201112 |  1 |
|       201112 |  2 |
|       201112 |  3 |
|       201201 |  1 |
|       201201 |  2 |
|       201201 |  3 |
+--------------+----+