查询时间间隔：
DATE(create_time) < DATE_SUB(CURDATE(), INTERVAL 1 DAY);
DATE(create_time) < DATE_SUB(CURDATE(), INTERVAL 7 month);
createtime < DATE_SUB(NOW(),INTERVAL 5 MONTH)
根据时间分类排序：
/*按天统计*/
GROUP BY DATE(create_time) ORDER BY DATE(create_time) DESC;


/*按周统计*/

GROUP BY WEEK(create_time) ORDER BY WEEK(create_time) DESC;


/*按月统计*/

GROUP BY MONTH(create_time) ORDER BY MONTH(create_time) DESC;


/*按季度统计*/

GROUP BY QUARTER(create_time) ORDER BY QUARTER(create_time) DESC;

/*按年统计*/

GROUP BY YEAR(create_time) ORDER BY YEAR(create_time) DESC;
/*查年示例写法*/
YEAR(createtime) YEAR

只查询年、月、日、小时、分钟或者组合查询：
格式:EXTRACT(unit FROM date)
unit支持的格式如下：
MICROSECOND, 
SECOND,  
MINUTE, 
HOUR, 
DAY, 
WEEK, 
MONTH, 
QUARTER, 
YEAR, 
DAY_MICROSECOND, 
HOUR_MICROSECOND, 
MINUTE_MICROSECOND, 
SECOND_MICROSECOND, 
DAY_HOUR, 
DAY_MINUTE, 
HOUR_MINUTE, 
DAY_SECOND, 
HOUR_SECOND, 
MINUTE_SECOND, 
YEAR_MONTH

获取当前时间 
yyyy-mm-dd hh:mm:ss  - now()
yyyy-mm-dd hh:mm:ss     - curdate()
yyyy-mm-dd hh:mm:ss     - curtime()

按小时分组查询
GROUP BY DATE_FORMAT( CREATETIME, '%Y-%m-%d %H' )

日期相减计算天数
TO_DAYS(日期)-TO_DAYS(日期)

查询时间：
今天
select * from 表名 where to_days(时间字段名) = to_days(now());

昨天SELECT * FROM 表名 WHERE TO_DAYS( NOW( ) ) - TO_DAYS( 时间字段名) <= 1

近7天SELECT * FROM 表名 where DATE_SUB(CURDATE(), INTERVAL 7 DAY) <= date(时间字段名)

近30天SELECT * FROM 表名 where DATE_SUB(CURDATE(), INTERVAL 30 DAY) <= date(时间字段名)

本月SELECT * FROM 表名 WHERE DATE_FORMAT( 时间字段名, '%Y%m' ) = DATE_FORMAT( CURDATE( ) , '%Y%m' )

上一月SELECT * FROM 表名 WHERE PERIOD_DIFF( date_format( now( ) , '%Y%m' ) , date_format( 时间字段名, '%Y%m' ) ) =1

查询本季度数据select * from `ht_invoice_information` where QUARTER(create_date)=QUARTER(now());

查询上季度数据select * from `ht_invoice_information` where QUARTER(create_date)=QUARTER(DATE_SUB(now(),interval 1 QUARTER));

查询本年数据select * from `ht_invoice_information` where YEAR(create_date)=YEAR(NOW());

查询上年数据select * from `ht_invoice_information` where year(create_date)=year(date_sub(now(),interval 1 year));

查询当前这周的数据SELECT name,submittime FROM enterprise WHERE YEARWEEK(date_format(submittime,'%Y-%m-%d')) = YEARWEEK(now());

查询上周的数据SELECT name,submittime FROM enterprise WHERE YEARWEEK(date_format(submittime,'%Y-%m-%d')) = YEARWEEK(now())-1;

查询上个月的数据select name,submittime from enterprise where date_format(submittime,'%Y-%m')=date_format(DATE_SUB(curdate(), INTERVAL 1 MONTH),'%Y-%m')
select * from user where DATE_FORMAT(pudate,'%Y%m') = DATE_FORMAT(CURDATE(),'%Y%m') ; 
select * from user where WEEKOFYEAR(FROM_UNIXTIME(pudate,'%y-%m-%d')) = WEEKOFYEAR(now()) 
select * from user where MONTH(FROM_UNIXTIME(pudate,'%y-%m-%d')) = MONTH(now()) 
select * from user where YEAR(FROM_UNIXTIME(pudate,'%y-%m-%d')) = YEAR(now()) and MONTH(FROM_UNIXTIME(pudate,'%y-%m-%d')) = MONTH(now()) 
select * from user where pudate between  上月最后一天  and 下月第一天
查询当前月份的数据 
select name,submittime from enterprise   where date_format(submittime,'%Y-%m')=date_format(now(),'%Y-%m')

查询距离当前现在6个月的数据select name,submittime from enterprise where submittime between date_sub(now(),interval 6 month) and now();