假設有一張oa_item_info(項目信息表),其中created爲項目建立時間字段sql
咱們來進行以下的搜索數據庫
1.查詢某年的數據函數
1.1 select * from oa_item_info where created like '2018-%';orm
1.2 select * from oa_item_info where left(created,4)='2018';blog
1.3 select * from oa_item_info where year(created)='2018';get
今年的數據:博客
select * from oa_item_info where year(created)=year(now());it
上一年的數據:form
select * from oa_item_info where year(created)=year(date_sub(now(),interval 1 year));date
date_sub()函數:date_sub
2.查詢某季度的數據
select QUARTER(created) as quartername ,created from oa_item_info ;
先看一下quarter函數返回的數據,第一列是quartername,第二列是created
1-3月返回1,4-6月返回2,7到9月返回3,10到12月返回4
並非搜索本季度的數據:
select * from oa_item_info where QUARTER(created)=QUARTER(now());
這條sql語句返回的是全部年份,當前季度的數據,好比如今是4月,會把全部年份4到6月的數據都檢索出來
搜索本季度的數據:
加上本年的限制條件
select * from oa_item_info where QUARTER(created)=QUARTER(now()) and year(created)=year(now());
3.查詢某月的數據
select month(created) as monthname,created from oa_item_info;
看一下返回數據:第一列是monthname,第二列是created
全部年份2月的數據
select * from oa_item_info where month(created)=2;
加上年份的限定條件就能夠了
4.查詢某周的數據
select week(created) as weekname,created from oa_item_info ;
看一下返回數據:第一列是weekname,第二列是created
返回的是一年中的第幾周
本週的數據:
select created from oa_item_info where week(created)=week(now()) and year(created)=year(now());
select * from oa_item_info where YEARWEEK(date_format(created,'%Y-%m-%d')) = YEARWEEK(now()) ;
看一下week和yearweek的區別:
數據庫中加入兩條週數一致的日期:
select week('2017-04-20');
select week('2018-04-25');
看一下yearweek的返回值:
select yearweek('2018-04-25');
看一下搜索結果:
select created from oa_item_info where week(created)=week(now());
week把兩條年份不同的都搜出來了
select created from oa_item_info where YEARWEEK(date_format(created,'%Y-%m-%d')) = YEARWEEK(now()) ;
select created from oa_item_info where YEARWEEK(created) = YEARWEEK(now()) ;
不用date_format函數也能夠
yearweek只搜出了今天的
值得注意的是,他們默認都是從週日開始算的,須要從週一開始計算時,須要加入第二個參數1:week(created,1)
date_format
上一週的數據:
select * from oa_item_info where YEARWEEK(date_format(created,'%Y-%m-%d')) = YEARWEEK(now())-1;
5.查詢某天的數據
今天的數據:
select created from oa_item_info where to_days(created) = to_days(now());
to_days();返回從0年開始的天數;
select to_days(now()) ;
from_days();根據天數,返回日期;
select from_days(737173) ;
昨天的數據:
這是不少博文的語句,看一下,如今是24號,會搜出今天和昨天數據
select created from oa_item_info where to_days(now())-to_days(created)<=1 ;
select created from oa_item_info where to_days(now())-to_days(created)=1 ;
搜出的是昨天的:
總結:
1.year(),從時間字段獲取年
2.quarter(),從時間字段獲取季度
3.month(),從時間字段獲取月
4.week(),從時間字段獲取周
5.yearweek(),從時間字段獲取年和周
6.date_sub(), 從時間字段減去指定時間間隔
7.date_format(),時間格式化
8.to_days(),返回從0年開始的天數;
9.from_days(),根據天數,返回日期;
SELECT * FROM `ex`.`receive` WHERE `channeleno` =12100444 TO_DAYS(`create_time`) = TO_DAYS(NOW()) ORDER BY `id` DESC LIMIT 0,50;
select * from 表 where date_format(日期,'%Y-%m-%d')='2014-04-01' 日期
select * from 表 where date_format(日期,'%Y-%m')='2014-04' 月份
select * from 表 where date_format(日期,'%Y')='2014' 年
就是date_format(日期,'%Y-%m-%d') 這裏的參數長短
基本就是這些了,之後遇到相關的知識我再補充,這是個人第一篇真正的技術博客,喜歡的話,記得點個贊!