`userid`, `dday`, `flag`) VALUES (7, 1, '2020-04-07', 0);
8INSERT INTO `testd`(`id`, `userid`, `dday...`id`, `userid`, `dday`, `flag`) VALUES (13, 2, '2020-04-01', 1);
14INSERT INTO `testd`(`id`, `userid`...`id`, `userid`, `dday`, `flag`) VALUES (20, 2, '2020-04-09', 1);
21INSERT INTO `testd`(`id`, `userid`...0, @pre_userid := null ) init
7ORDER BY
8 userid, dday
其中增加了一个自定义变量@preuser,表示当前行的前一条记录用户信息。...'
4FROM
5 (SELECT
6 userid, dday, flag,
7 @pre_check := IF(userid = @pre_userid