SQLÓï¾äÖÐ N ºó½ÓÐø×Ö·û´®µÄ×÷ÓÃ
È磺SET @sql=N'SELECT * from stu'
ÆäÖГN”µÄ×÷ÓÃÊDZíʾºóÃæµÄ±àÂë¸ñʽΪunicode±àÂë
DECLARE @rst INT,@sql NVARCHAR(4000)
SET @sql=N'SELECT * from tb '
EXEC sp_executesql @sql,N'@rst INT OUTPUT',@rst OUTPUT
SELECT @rst
Ïà¹ØÎĵµ£º
1½«sqlÖÐʹÓõÄһЩÌØÊâ·ûºÅ£¬Èç' -- /* ; %µÈÓÃReplace()¹ýÂË£»
2ÏÞÖÆÎı¾¿òÊäÈë×Ö·ûµÄ³¤¶È£»
3¼ì²éÓû§ÊäÈëµÄºÏ·¨ÐÔ£»¿Í»§¶ËÓë·þÎñÆ÷¶Ë¶¼ÒªÖ´ÐУ¬¿ÉÒÔʹÓÃÕýÔò¡£
4ʹÓôø²ÎÊýµÄSQLÓï¾äÐÎʽ¡£
ASP.NETÖÐÈçºÎ·À·¶SQL×¢Èëʽ¹¥»÷
Ò»¡¢Ê²Ã´ÊÇSQL×¢Èëʽ¹¥»÷£¿
¡¡¡¡ËùνSQL×¢Èëʽ¹¥»÷£¬¾ÍÊǹ¥»÷Õß°Ñ ......
½ñÌìÔÚÓÃJTDSÁ¬½ÓSQL Server ʱºò£¬Óöµ½¼¸¸öÎÊÌ⣬¼Ç¼ÈçÏ£º
error while performing database login with the jtds driver:
network error ioexception:connection refused: connect
È»ºó²é¿´¶Ë¿Ú£¬ÔÀ´ÊÇ1433¶Ë¿Úδ´ò¿ª£¬È»ºóÔÚSQL Server configuration ManagerϵÄTCP\IPÖÐÆôÓÃ1433¶Ë¿Ú£¬ÖØÆôSQL Server·þÎñ£¬netst ......
--¾ÛºÏº¯Êý
use pubs
go
select avg(distinct price) --Ëãƽ¾ùÊý
from titles
where type='business'
go
use pubs
go
select max(ytd_sales) --×î´óÊý
from titles
go
use pubs
go
select min(ytd_sales)& ......
SQlÊý¾ÝÀàÐÍ(-_-ѧSQL¾Í´ÓÊý¾ÝÀàÐÍ¿ªÊ¼°É£¡)
bit ÕûÐÍ
ÆäÖµÖ»ÄÜÊÇ0¡¢1»ò¿ÕÖµ¡£
ÕâÖÖÊý¾ÝÀàÐÍÓÃÓÚ´æ´¢Ö»ÓÐÁ½ÖÖ¿ÉÄÜÖµµÄÊý¾Ý£¬ÈçYes »òNo¡¢True »òFalse ¡¢On »òOff.
int ÕûÐÍ 4¸ö×Ö½Ú
´Ó- 2^31(-2147483648)µ½2^31 (2147483 647)Ö®¼äµÄÕûÊý¡£
´æ´¢µ½Êý¾Ý¿âµÄ¼¸ºõËùÓÐÊýÖµÐ͵ÄÊý¾ ......
Select TOP N * from TABLE Order By NewID()
--Access£º
Select TOP N * from TABLE Order By Rnd(ID)
Rnd(ID) ÆäÖеÄIDÊÇ×Ô¶¯±àºÅ×ֶΣ¬¿ÉÒÔÀûÓÃÆäËûÈκÎÊýÖµÀ´Íê³É£¬±ÈÈçÓÃÐÕÃû×Ö¶Î(UserName)
Selec ......