Ò׽ؽØÍ¼Èí¼þ¡¢µ¥Îļþ¡¢Ãâ°²×°¡¢´¿ÂÌÉ«¡¢½ö160KB

ÇóÒ»SQL - .NET¼¼Êõ / C#

ÏÖÓÐÁ½¸ö±í

  ±í1 user (Óû§ÐÅÏ¢ )  

  username password  
  A 123  
  B 000
  C 555




±í2 record (Óû§¼Ç¼)
  id username logintime
  1 C 2009-10-10
  2 A 2009-10-11
  3 A 2009-10-12
  4 B 2009-10-13
  5 B 2009-10-15
  6 C 2009-10-16


±í2 idÁÐÊÇ×Ô¶¯±àºÅ£¬recordtimeÊÇ×îºóµÇ½ʱ¼äʱ¼ä£¬ÏÖÔÚÒªÏÔʾ±í1µÄËùÓÐÐÅÏ¢ ¼°×îºó¼Ç¼ʱ¼ä,½á¹ûÓ¦¸ÃÈçÏÂ

username password logintime
A 123 2009-10-12
B 000 2009-10-15
C 555 2009-10-16

ÇëÎÊÕâÌõSQLÓï¾äÈçºÎд



   



ÎÒ»¹ÔÚѧ£¬µÈÎÒѧ»áÁ˽ÌÄã°¡£¬¸Â¸Â...

select username,password,(select top 1 logintime from record where record.username=[user].username order by logintime desc ) from [user] 


select a.*,b.lasttime from user as a 
left join
(select max(logintime)as lasttime,username from record group by username)
as b
on a.username = b.username

select t1.*,t2.lasttime from user t1 
left join
(select username,max(logintime)as lasttime from record g


Ïà¹ØÎÊ´ð£º

Çë½ÌsqlÓï¾ä¡£ - Oracle / ¿ª·¢

ÎÒÓÐÒ»¸ö±í£¬½á¹¹ÊÇÕâÑù¡£
  ת³ö µ¥Î» תÈ뵥λ ±ÊÊý ½ð¶î
date(Ö÷) outid(Ö÷) inid(Ö÷) num amt
2009 1 2 1 500 Ϊ 1 µ¥Î» ÔÚ2009Ä ......

sqlССµÄÒÉÎÊ - .NET¼¼Êõ / C#

¿ÉÄÜÒòΪ¹¤×÷µÄÔ­Òò ½Ó´¥Êý¾Ý¿âÕâ¿é±È½ÏÉÙ£¬Ö®Ç°¶¼ÊÇ×ö³ÌÐòÕâ¿é£¬Êý¾Ý¿âÕâ¿é¶¼ÓÐרÃŵÄÈËÀ´×ö ·Ö¹¤¶¼ºÜÃ÷ϸ ËùÒÔ¶ÔÊý¾Ý¿âÕâÒ»¿éÍêÈ«²»Á˽⡣ǰ¶Îʱ¼ä È¥ÃæÊÔÁ˼¸¼Ò¹«Ë¾ ¼¸ºõ¶¼ÊÇÔÚÊý¾Ý¿âÕâ¿é¹ÒµôµÄ Á¬¸ö¼òµ¥µÄSQ ......

Çë½ÌSQLSERVERµÄÁ½¸öÎÊÌâ - MS-SQL Server / ÒÉÄÑÎÊÌâ

1¡£ÔõÑùʹxp_cmdshellÄÜÍêÕûÊä³ö³¬¹ý255¸ö×Ö·ûµÄ×Ö·û´®¡£
2¡£select ʱ£¬¼ìË÷ËÙ¶ÈÊÇÓëfromºóµÄ TABLE˳ÐòÓйأ¬»¹ÊÇÓëwhereÌõ¼þµÄ˳ÐòÓйØ(TABLEÊý¾Ý¶àÉÙ )
ÔÚϵͳÊôÐÔÉ趨ÀïÓиöÑ¡Ïî,¿ÉÒÔÐ޸ĵ¥×Ö¶ÎÊä³ö×ÖÊýÏÞÖÆ. ......

VS2008²Ù×÷AccessÎÊÌâ - .NET¼¼Êõ / C#

VS2008ÖÐC#²Ù×÷AccessÊý¾Ý¿â£¬ÍøÉÏÏÂÔØÁËÒ»¸öÀ࣬¿ÉÒÔÕý³£Á¬½Ó£¬¶ÁÈ¡Êý¾Ý£¬µ«ÊDzåÈëɾ³ý²Ù×÷ËÆºõÓÐÎÊÌ⣬ÒÔÏÂÊDz¿·Ö´úÂ룺
Êý¾Ý¿âÀࣺ
namespace AccessDb
{
  public class AccessDbClass
  { ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØÍ¼ | ¸ÓICP±¸09004571ºÅ