SQL²ÎÊý»¯
SqlCommand com = new SqlCommand("select * from myuser where username=@UserName and password=@Pwd", con);
com.Parameters.Add(new SqlParameter("@UserName", UserName));
com.Parameters.Add( new SqlParameter("@Pwd",Pwd));
Ïà¹ØÎĵµ£º
ϵͳ»·¾³£ºWindows 7
Èí¼þ»·¾³£ºVisual C++ 2008 SP1 +SQL Server 2005
±¾´ÎÄ¿µÄ£º±àдһ¸öº½¿Õ¹ÜÀíϵͳ
ÕâÊÇÊý¾Ý¿â¿Î³ÌÉè¼ÆµÄ³É¹û£¬ËäÈ»³É¼¨²»¼Ñ£¬µ«ÊÇ×÷ΪÎÒÓÃVC++ ÒÔÀ´±àдµÄ×î´ó³ÌÐò»¹ÊÇ´«µ½ÍøÉÏ£¬ÒÔ¹©²Î¿¼¡£ÓÃVC++ ×öÊý¾Ý¿âÉè¼Æ²¢²»ÈÝÒ×£¬µ«Ò²²»ÊDz»¿ÉÄÜ¡£ÒÔÏÂÊÇÎҵijÌÐò½çÃæ£¬ºóÃæ ......
1. µ±Ç°ÏµÍ³ÈÕÆÚ¡¢Ê±¼ä
select getdate()
2. dateadd ÔÚÏòÖ¸¶¨ÈÕÆÚ¼ÓÉÏÒ»¶Îʱ¼äµÄ»ù´¡ÉÏ£¬·µ»ØÐ嵀 datetime Öµ
ÀýÈ磺ÏòÈÕÆÚ¼ÓÉÏ2Ìì
select dateadd(day,2,'2004-10-15') --·µ»Ø£º2004-10-17 00:00:00.000
3. datediff ·µ»Ø¿çÁ½¸öÖ¸¶¨ÈÕÆÚµÄÈÕÆÚºÍʱ¼ä ......
Ò»¡¢Êʺ϶ÁÕß¶ÔÏó
Êý¾Ý¿â¿ª·¢³ÌÐòÔ±£¬Êý¾Ý¿âµÄÊý¾ÝÁ¿ºÜ¶à£¬Éæ¼°µ½¶ÔSP(´æ´¢¹ý³Ì)µÄÓÅ»¯µÄÏîÄ¿¿ª·¢ÈËÔ±£¬¶ÔÊý¾Ý¿âÓÐŨºñÐËȤµÄÈË¡£
¶þ¡¢½éÉÜ
ÔÚÊý¾Ý¿âµÄ¿ª·¢¹ý³ÌÖУ¬¾³£»áÓöµ½¸´ÔÓµÄÒµÎñÂß¼ºÍ¶ÔÊý¾Ý¿âµÄ²Ù×÷£¬Õâ¸öʱºò¾Í»áÓÃSPÀ´·â×°Êý¾Ý¿â²Ù×÷¡£Èç¹ûÏîÄ¿µÄSP½Ï¶à£¬ÊéдÓÖûÓÐÒ»¶¨µÄ¹æ
·¶£¬½«»áÓ°ÏìÒÔºóµÄϵͳά»¤À§ÄÑ ......
ORACLE SQLÐÔÄÜÓÅ»¯ÏµÁÐ
1. ·ÃÎÊTableµÄ·½Ê½
ORACLE ²ÉÓÃÁ½ÖÖ·ÃÎʱíÖмǼµÄ·½Ê½:
a. È«±íɨÃè
È«±íɨÃè¾ÍÊÇ˳ÐòµØ·ÃÎʱíÖÐÿÌõ¼Ç¼. ORACLE²ÉÓÃÒ»´Î¶ÁÈë¶à¸öÊý¾Ý¿é(database block)µÄ·½Ê½ÓÅ»¯È«±íɨÃè.
b. ͨ¹ýROWID·ÃÎʱí
Äã¿ÉÒÔ²ÉÓûùÓÚROWIDµÄ·ÃÎÊ·½Ê½Çé¿ö,Ìá¸ß·ÃÎʱíµÄЧÂÊ, , ROWID°üº¬Á˱íÖмǼµ ......
ÎÒÃÇÔÚÊý¾Ý¿âÖÐʹÓñíµÄʱºò,¾³£»áÓöµ½Á½ÖÖʹÓñíµÄ·½·¨,·Ö±ð¾ÍÊÇʹÓÃÁÙʱ±í¼°±í±äÁ¿¡£ÔÚʵ¼ÊʹÓõÄʱºò£¬ÎÒÃÇÈçºÎÁé»îµÄÔÚ´æ´¢¹ý³ÌÖÐÔËÓÃËüÃÇ£¬ËäÈ»ËüÃÇʵÏֵŦÄÜ»ù±¾ÉÏÊÇÒ»ÑùµÄ£¬¿ÉÈçºÎÔÚÒ»¸ö´æ´¢¹ý³ÌÖÐÓÐʱºòȥʹÓÃÁÙʱ±í¶ø²»Ê¹Óñí±äÁ¿£¬ÓÐʱºòȥʹÓñí±äÁ¿¶ø²»Ê¹ÓÃÁÙʱ±íÄØ?
¡¡¡¡ÁÙʱ±í
¡¡¡¡ÁÙʱ±íÓëÓÀ¾Ã±íÏàËÆ£¬ ......