mysql数据库默认时间字段格式

date

YYYY-mm-dd格式  时分秒%Y%m%d

time   时分秒%H%m%s

datetime   %Y%m%d %H%m%s  YYYY-mm-dd HH:ss:mm

timestamp   YYYYmmddHHssmm

riqi查询

and   DATE_FORMAT(a.contract_time,'%Y-%m-%d')
between  DATE_FORMAT(#{contractTime},'%Y-%m-%d')
and      DATE_FORMAT(#{contractTimeEnd},'%Y-%m-%d')