MySQL 查询技巧

查询七天内的数据

select count(*)as count from hvac_alarm where COMPANY_ID= #{companyId}  and ISDEL=0 and DATE_SUB(CURDATE(), INTERVAL 7 DAY)<= date(CREATE_TIME)


分页查询

select @y:=@y + 1 AS num,a.ALARM_MESSAGE,a.CREATE_TIME,e.NAME,e.ADDRESS from  (SELECT @y:= 0) c,
(select ID,ISREAD, CASE ALARM_TYPE > 2 WHEN 1 THEN '设备告警' ELSE '数据告警' END AS ALARM_TYPE,ALARM_MESSAGE,DATA_ID,DEVICE_ID,CREATE_TIME,ISDEL from
hvac_alarm where ISDEL = 0 and COMPANY_ID=#{companyId} order by CREATE_TIME desc LIMIT 1000

日期格式化

date_format(#{date},'%Y-%m-%d')

STR_TO_DATE(#{date1},'%Y-%m-%d %H:%i:%s')