Plus 7 days
Date field = DATE_ADD (fixed date field, INTERVAL UPDATE SET modified table . 7 DAY) the WHERE condition ~~~
UPDATE 表名 SET cretime=DATE_ADD(decdate,INTERVAL 7 DAY) WHERE 条件~~~~
cretime as being modified fields, decdate queried for the time field plus 7 days time field into cretime
Save 7 days
- date field = DATE_ADD (fixed date field, INTERVAL UPDATE SET modified table . 7 the WHERE condition DAY ~~~) the UPDATE table cretime SET = DATE_ADD (decdate, the INTERVAL - . 7 DAY) the WHERE condition ~~~~ cretime as being modified field, decdate queried for the time field minus 7 days time field into cretime