SQL»ñȡʱ¼äº¯Êý
DATEDIFF(²ÎÊýÒ»,²ÎÊý¶þ,²ÎÊýÈý) ---²ÎÊýÒ»£ºyear month day; ²ÎÊý¶þ£º±È½ÏµÄÆðʼÈÕÆÚ,ĬÈÏ1900-1-1£»²ÎÊýÈý£º±È½ÏµÄÈÕÆÚ¡£
eg:DATEDIFF(year,0,getdate())±íʾ±È½Ï0£¨Ä¬ÈÏ1900-1-1£©µ½µ±Ç°µÄÈÕÆÚÏë²î¼¸Äê
SELECT DATEADD(mm, DATEDIFF(mm,0,getdate()), 0) -- È¡µÃ±¾ÔµĵÚÒ»Ìì
SELECT DATEADD(wk, DATEDIFF(wk,0,getdate()), 0) -- È¡µÃ±¾ÖܵÄÐÇÆÚÒ»
SELECT DATEADD(yy, DATEDIFF(yy,0,getdate()), 0) -- È¡µÃ±¾ÄêµÄµÚÒ»Ìì
SELECT dateadd(ms,-3,DATEADD(mm, DATEDIFF(mm,0,getdate()), 0)) --ÉϸöÔÂ×îºóÒ»Ìì
SELECT dateadd(ms,-3,DATEADD(mm, DATEDIFF(mm,0,getdate())+1, 0)) --±¾ÔÂ×îºóÒ»Ìì
SELECT dateadd(m,0,dateadd(yy,datediff(yy,0,getdate()),0)) --È¡µÃ±¾ÄêµÚÒ»ÔÂ
Ïà¹ØÎĵµ£º
SELECT CONVERT(varchar(100), GETDATE(), 0): 05 16 2006 10:57AM
SELECT CONVERT(varchar(100), GETDATE(), 1): 05/16/06
SELECT CONVERT(varchar(100), GETDATE(), 2): 06.05.16
SELECT CONVERT(varchar(100), GETDATE(), 3): 16/05/06
SELECT CONVERT(varchar(100), GETDATE(), 4): 16.05.06
SELECT CONVERT(varch ......
SQL×¢Èëʽ¹¥»÷ÊÇÀûÓÃÊÇÖ¸ÀûÓÃÉè¼ÆÉϵÄ©¶´£¬ÔÚÄ¿±ê·þÎñÆ÷ÉÏÔËÐÐSqlÃüÁîÒÔ¼°½øÐÐÆäËû·½Ê½µÄ¹¥»÷¶¯Ì¬Éú³ÉSqlÃüÁîʱûÓжÔÓû§ÊäÈëµÄÊý¾Ý½øÐÐÑéÖ¤ÊÇSql×¢Èë¹¥»÷µÃ³ÑµÄÖ÷ÒªÔÒò¡£
±ÈÈ磺
Èç¹ûÄãµÄ²éѯÓï¾äÊÇselect * from admin where username="&user&" and password="&pwd&""
ÄÇô£¬Èç¹ûÎÒµÄÓû§ÃûÊ ......
±íÖÐÖ÷¼ü±ØÐëΪ±êʶÁУ¬[ID] int IDENTITY (1,1)
1.·ÖÒ³·½°¸Ò»£º(ÀûÓÃNot InºÍSELECT TOP·ÖÒ³)
Óï¾äÐÎʽ£º
SELECT TOP Ò³¼Ç¼ÊýÁ¿ *
from ±íÃû
WHERE (ID NOT IN
(SELECT TOP (ÿҳÐÐÊý*(Ò³Êý-1)) ID
from ±íÃû
ORDER BY ID))
ORDER BY ID
//×Ô¼º»¹¿ÉÒÔ¼ÓÉÏһЩ²éѯÌõ¼þ
Àý:
sele ......
Random rnd = new Random(unchecked((int)DateTime.Now.Ticks));
int intRandomNumber = rnd.Next();
&nb ......