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?
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- doulie0178 2011-10-26 12:25关注
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 | +--------------+----+
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