Ò׽ؽØͼÈí¼þ¡¢µ¥Îļþ¡¢Ãâ°²×°¡¢´¿ÂÌÉ«¡¢½ö160KB

SQL 2005 CHECKÔ¼ÊøºÍ¹æÔòÇø±ð


Ò»¡¢Ô¼Êø   
      Ô¼Êø¶¨Òå¹ØÓÚÁÐÖÐÔÊÐíÖµµÄ¹æÔò£¬ÊÇÇ¿ÖÆÍêÕûÐԵıê×¼»úÖÆ¡£
      Ê¹ÓÃÔ¼ÊøÓÅÏÈÓÚʹÓô¥·¢Æ÷¡¢¹æÔòºÍĬÈÏÖµ¡£²éѯÓÅ»¯Æ÷ҲʹÓÃÔ¼Êø¶¨ÒåÉú³É¸ßÐÔÄܵIJéѯִÐмƻ®¡£SQL Server 2005Ö§³ÖÎåÀàÔ¼Êø£º  
      1. NOT NULLÖ¸¶¨²»½ÓÊÜNULLÖµµÄÁС£      
      2. CHECK Ô¼Êø¶Ô¿ÉÒÔ·ÅÈëÁÐÖеÄÖµ½øÐÐÏÞÖÆ£¬ÒÔÇ¿ÖÆÖ´ÐÐÓòµÄÍêÕûÐÔ¡£CHECKÔ¼Êø¾Ü¾øËùÓÐÔÚ¼ì²âÌõ¼þÖÐȡֵΪfalseµÄÖµ¡£¿ÉÒÔΪÿÁÐÖ¸¶¨¶à¸öCHECKÔ¼Êø¡£ÏÂÀýÏÔʾÃûΪchk_idÔ¼ÊøµÄ´´½¨£¬¸ÃÔ¼ÊøÈ·±£Ö»¶Ô´Ë¹Ø¼ü×ÖÊäÈëÖ¸¶¨·¶Î§ÄÚµÄÊý×Ö£¬ÒÔ½øÒ»²½Ç¿ÖÆÖ´ÐÐÖ÷¼üµÄÓò¡£
CREATE TABLE cust_sample   
          (   
          cust_id int PRIMARY KEY,   
          cust_name char(50),   
          cust_address char(50),   
          cust_credit_limit money,   
          CONSTRAINT chk_id CHECK(cust_id BETWEEN 0 and 10000)   
          )   
3. UNIQUEÔ¼Êø£º¶ÔÓÚ UNIQUE Ô¼ÊøÖеÄÁУ¬±íÖв»ÔÊÐíÓÐÁ½Ðаüº¬ÏàͬµÄ·Ç¿ÕÖµ¡£Ö÷¼üҲǿÖÆÖ´ÐÐΨһÐÔ£¬µ«Ö÷¼ü²»ÔÊÐí¿ÕÖµ¡£UNIQUE   Ô¼ÊøÓÅÏÈÓÚΨһË÷Òý¡£   
      4. PRIMARY KEY Ô¼Êø±êʶÁлòÁм¯£¬ÕâЩÁлòÁм¯µÄֵΨһ±êʶ±íÖеÄÐС£ÔÚÒ»¸ö±íÖУ¬²»ÄÜÓÐÁ½Ðаüº¬ÏàͬµÄÖ÷¼üÖµ¡£²»ÄÜÔÚÖ÷¼üÄÚµÄÈκÎÁÐÖÐÊäÈëNULLÖµ¡£ÔÚÊý¾Ý¿âÖÐNULLÊÇÌØÊâÖµ£¬´ú±í²»Í¬Óڿհ׺Í0ÖµµÄδֵ֪¡£½¨ÒéʹÓÃÒ»¸öСµÄÕûÊýÁÐ×÷ΪÖ÷¼ü¡£Ã¿¸ö±í¶¼Ó¦ÓÐÒ»¸öÖ÷¼ü¡£
      Ò»¸ö±íÖпÉÒÔÓÐÒ»¸öÒÔÉϵÄÁÐ×éºÏ£¬ÕâЩ×éºÏÄÜΨһ±êʶ±íÖеÄÐУ¬Ã¿¸ö×éºÏ¾ÍÊÇÒ»¸öºòÑ¡¼ü¡£Êý¾Ý¿â¹ÜÀíÔ±´ÓºòÑ¡¼üÖÐÑ¡ÔñÒ»¸ö×÷ΪÖ÷¼ü¡£ÀýÈ磬ÔÚpart_sample±íÖУ¬part_nmbrºÍpart_name¶¼¿ÉÒÔÊǺòÑ¡¼ü£¬µ«ÊÇÖ»½«part_nmbrÑ¡×÷Ö÷¼ü¡£
CREATE TABLE part_sample   
          (
          


Ïà¹ØÎĵµ£º

SQL ÓαêÔ­ÀíºÍʹÓ÷½·¨

 Êý¾Ý¿â¿ª·¢¹ý³ÌÖУ¬µ±Äã¼ìË÷µÄÊý¾ÝÖ»ÊÇÒ»Ìõ¼Ç¼ʱ£¬ÄãËù±àдµÄÊÂÎñÓï¾ä´úÂëÍùÍùʹÓÃSELECT INSERT Óï¾ä¡£µ«ÊÇÎÒÃdz£³£»áÓöµ½ÕâÑùÇé¿ö£¬¼´´Óijһ½á¹û¼¯ÖÐÖðÒ»µØ¶ÁÈ¡Ò»Ìõ¼Ç¼¡£ÄÇôÈçºÎ½â¾öÕâÖÖÎÊÌâÄØ£¿ÓαêΪÎÒÃÇÌṩÁËÒ»ÖÖ¼«ÎªÓÅÐãµÄ½â¾ö·½°¸¡£
      1.1 ÓαêºÍÓαêµÄÓŵã
  & ......

sql´æ´¢

declare @p int
declare @p1 int
declare @count int
set @p=0
set @p1=10
set @count=2
if(@count<>0 or @count<>1)
set @p=@p1*@count-10
SELECT [t1].[userid], [t1].[username], [t1].[userorder]
from (
    SELECT ROW_NUMBER() OVER (ORDER BY [t0].[userorder]) AS [ROW_NU ......

MySqlµÄ¼òµ¥Ð޸ıí×Ö¶ÎSQLÓï¾ä

#ÐÂÔöÒ»¸ö×ֶΣ¬Ä¬ÈÏֵΪ0£¬·Ç¿Õ£¬×Ô¶¯Ôö³¤£¬Ö÷¼ü
   alter table tabelname add new_field_name field_type default 0 not null auto_increment ,add primary key (new_field_name);
#Ôö¼ÓÒ»¸öÐÂ×Ö¶Î
   alter table tableName add new_field_name field_type;
   alter table tableNam ......

¹¦ÄÜÇ¿´óµÄSQLÓï¾ä

1. ¸´ÖƱí½á¹¹
Sql´úÂë
   1. select * into B from A where 1=0;   
select * into B from A where 1=0;
 2.¸´ÖƱí¼Ç¼ ¸´ÖÆijЩ×Ö¶Î
Sql´úÂë
   1. insert into B(a, b, c) select d, e, f from A;   
insert into B(a, b, c) select d, e, f from A;
  ¸´Ö ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØͼ | ¸ÓICP±¸09004571ºÅ