SQL ֪ʶ
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use master
if exists(select * from databases where name='¿âÃû')
drop database ¿âÃû
__________________________ ½¨Êý¾Ý¿â½¨±íµÄ»ù±¾¸ñʽ ___________________________________________
create database ¿âÃû
on primary
(name='student1',filename='·¾¶\student1.mdf',size=10mb, filegrowth=15%), Ö÷Îļþ
(name='student2',filename='·¾¶\student2.ndf',size=10mb, filegrowth=15%) ´ËÎļþ
log on
(name='student1_log',filename='·¾¶\student1.ldf',size=1mb,filegrowth=15%,maxsize=300mb), ÈÕÖ¾Îļþ
(name='student2_log',filename='·¾¶\student2.ldf',size=1mb,filegrowth=15%,maxsize=300mb)
go
use ¿âÃû
create table ±íÃû
(ÁÐÃû1 Êý¾ÝÀàÐÍ Ö÷¼ü ÊÇ·ñÔö³¤ Ψһ ĬÈÏ ÊÇ·ñΪ¿Õ£¬
name varchar primary key identity(±íʾÖÖ×Ó£¬Ôö³¤Á¿) unique default not null,
)
-------------------------½¨Êý¾Ý¿â±íÖ®¼äµÄÔ¼Êø-------------------------------------------------------
alter table kk add
df ĬÈÏ constraint df_sex default(nan) for sex
pk Ö÷¼ü constraint pk_ÁÐÃû primary key(ÁÐÃû)
ck ¼ì²é constraint ck_ÁÐÃû check(len(ÁÐÃû)>=6)
constraint ck_ÁÐÃû check(ÁÐÃû like [email='%@%']'%@%'[/email])
fk Ö÷Íâ¼ü constraint fk_Íâ¼üÁÐÃû foreign key(Íâ¼üÁÐÃû) references Ö÷±íÃû£¨Ö÷±íÁУ©
uq Ψһ
Ïà¹ØÎĵµ£º
±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
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Me.DsUserManager1.Tables(0).Select("id > 5 and id <20")
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