


This article mainly introduces MYSQL to realize the continuous sign-in function and start from scratch after one day. It is very good and has reference value. Friends who need it can refer to it
1 , create test table
CREATE TABLE `testsign` ( `userid` int(5) DEFAULT NULL, `username` varchar(20) DEFAULT NULL, `signtime` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, `type` int(1) DEFAULT '0' COMMENT '为0表示签到数据,1表示签到日期字典数据' ) ENGINE=InnoDB DEFAULT CHARSET=utf8
2, insert test data, check-in time is from 5.21 to 6.5, you can write live, but you need to write stored procedure, I compare Lazy, the focus should be on the code to get the sign-in data, which is the third point, haha
insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-05-21 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-05-22 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-05-23 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-05-24 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-05-25 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-05-26 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-05-27 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-05-28 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-05-29 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-05-30 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-05-31 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-06-01 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-06-02 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-06-03 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-06-04 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('72164','字典','2017-06-05 00:00:00','1'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('800675','吴小双签到数据','2017-05-21 00:00:00','0'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('800675','吴小双签到数据','2017-05-22 00:00:00','0'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('800675','吴小双签到数据','2017-05-23 00:00:00','0'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('800675','吴小双签到数据','2017-05-24 00:00:00','0'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('800675','吴小双签到数据','2017-05-25 00:00:00','0'); insert into `testsign` (`userid`, `username`, `signtime`, `type`) values('800675','吴小双签到数据','2017-05-26 00:00:00','0');
3,QueryContinuous sign-in data
SELECT * FROM testsign WHERE TYPE=0 AND DATE_FORMAT(signtime,'%Y%m%d')>( SELECT IFNULL(MAX(DATE_FORMAT(signtime,'%Y%m%d')),"20170520") FROM testsign WHERE TYPE=1 AND DATE_FORMAT(signtime,'%Y%m%d')<=DATE_ADD(NOW(), INTERVAL -1 DAY) AND DATE_FORMAT(signtime,'%Y%m%d') NOT IN ( SELECT DATE_FORMAT(signtime,'%Y%m%d') FROM testsign WHERE TYPE=0 AND userid=800675 ) ) AND DATE_FORMAT(signtime,'%Y%m%d')<='20170605' AND userid=800675
Unbroken data
Delete the data on the 23rd, count from the 24th, and sign for three consecutive days
# #
The above is the detailed content of Detailed explanation of how MYSQL implements the function of continuously signing in and starting from scratch for one day (picture). For more information, please follow other related articles on the PHP Chinese website!

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