select * from ( select c.OrderNumber , c.Name as equipmentName, a.*, d.Starttime, d.Endtime, ( select datediff(d.Starttime, d.Endtime)) as Lev , case ( select datediff(d.Starttime, d.Endtime)) when ( select datediff(d.Starttime,…
表TESTER 字段:id -- INT date -- TIMESTAMP 1.如何按年.月.日分组查询? select DATE_FORMAT(date,'%Y-%m-%d') time, count(*) count from TESTER group by year(date), month(date), day(date); 其中year().month().day()分别是提取date中的年.月.日字段. 2.时间分组查询的效率? 在不建立索引时,我100W行数据进行测试,用…
Mysql 时间格式默认插入值为空时,会以'0000-00-00 00:00:00'填充,这时如果select时会抛出SQLExecption如下: java.sql.SQLException: Value '0000-00-00 00:00:00' can not be represented as java.sql.Timestamp 解决方法如下: 方法一:jdbc的url加zeroDateTimeBehavior参数: datasource.url=jdbc:mysql://localh…
原文地址:http://www.jb51.net/article/60177.htm using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace Test { class Program { static void Main(string[] args) { DateTime t1 = DateTime.Parse("2007-01-01"); DateT…
转自:https://blog.csdn.net/iteye_8535/article/details/82246006 JAVA时间进行比较和转换,时间加减得到天数 1. 把时间类型的字符串转为DATE import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Date; public class Text { public static void main(String[] arg…