


Simple! Just one step to help you use mysql to implement date and time query
mysql Query the data within a specified date based on the timestamp Not everyone knows how to query the time period in MySql. Here is a method of querying the time period in MySql for your reference. I hope it can inspire you.
select now();--当前日期及时间 2018-07-25 14:29:36 select LAST_DAY('2018-02-01'); --返回月份中的最后一天 2018-02-28 select DATE_FORMAT(now(),'%Y-%m-%d %H:%m:%S') --格式化输出 2018-07-25 14:07:18 select '2018-07-25' =(select DATE_FORMAT(now(),'%Y-%m-%d')); --判断当前日期是否与指定日期相等,返回0表示不相等,1表示相等 1 set @dt= (SELECT DATE_FORMAT(now(),'%Y-%m-%d %H:%i:%s')); --格式化当前日期和时间,并赋值给@dt SELECT @dt;--2018-07-25 14:33:50 SELECT DATE(@dt);--2018-07-25 SELECT TIME(@dt); --14:33:50 SELECT DATE(NOW()); --只输出当前日期 2018-07-25 SELECT TIME(NOW()); --只输出当前时间 14:36:19 SELECT YEAR(now()); --2018 SELECT month(now()); --7 select day(now()); --25 SELECT time(now()) time1 , sleep(3) ,time(now()) time2; --中间睡眠3s钟 time1和time2的时间也是一样的 14:43:54 0 14:43:54 SELECT time(SYSDATE()) time1,sleep(3),time(SYSDATE()) time2; --中间睡眠3s钟 time1和time2的时间相差3s 14:43:15 0 14:43:18 --其他获取当前日期和时间的函数 select CURRENT_DATE,CURRENT_TIME,CURRENT_USER,LOCALTIME,LOCALTIMESTAMP,date(LOCALTIME),date(LOCALTIMESTAMP),time(LOCALTIME);--2018-07-25 14:48:30 root@localhost 2018-07-25 14:48:30 2018-07-25 14:48:30 2018-07-25 2018-07-25 14:48:30 set @dt='2018-02-14 14:22:23'; SELECT DAYOFMONTH('2018-02-14') --一月的第几天 14 SELECT DAYOFWEEK('2018-02-14') --一周的第几天 注:从周日算起 4 SELECT DAYOFYEAR(@dt) --一年的第几天 45 select WEEKOFYEAR(@dt) --一年的第几周 7
Format the date value according to the format string:
%S, %s seconds in two-digit format (00,01, ..., 59)
%I, %i two-digit minute (00,01, ..., 59)
%H two-digit number Numeric hour, 24 hours (00,01, ..., 23)
%h Two-digit hour, 12 hours (01,02, ..., 12)
%k hour in numeric form, 24 hours (0,1, ..., 23)
%l numeric form hour, 12 hours (1, 2, ..., 12)
%T 24-hour time format (hh:mm:ss)
%r 12-hour time format (hh:mm:ss AM or hh:mm:ss PM)
%p AM or PM
%W The name of each day of the week (Sunday, Monday, ..., Saturday)
%a The abbreviation of the name of each day of the week (Sun, Mon, ..., Sat)
%d Two digits represent the number of days in the month (00, 01,..., 31)
%e The number form represents the number of days in the month (1, 2, ..., 31)
%D The English suffix represents the number of days in the month (1st, 2nd, 3rd,. ..)
%w represents the day of the week in numeric form (0 = Sunday, 1=Monday, ..., 6=Saturday)
%j represents the number of days in the year (001, 002, ..., 366) with three digits
%U week (0, 1, 52), where Sunday is the first day of the week
%u week (0, 1, 52), where Monday is the first day of the week
%M Month name (January, February, ..., December)
-
%b Abbreviated month name (January, February, ...., December)
%m The month represented by two digits (01, 02, ..., 12)
%c The month represented by digits (1, 2 , ...., 12)
%Y The year represented by four digits
%y The year represented by two digits
%% direct value "%"
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