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  • 视图,索引

    create view  testview

    as

    聚集索引     表中数据行的物理存储顺序与索引顺序完全相同

    非聚集索引 不改变表中数据行的物理存储顺序,数据与索引分开存储,索引中仅包含 索引值和指向数据行的指针

    create unique clustered index ix_briday on dbo.stu --nonclustered
    (
    id asc
    )

    sp_helpindex stu

    exec sp_rename 'stu.new_index_name','index_test','index'

    drop index stu.index_test

    set showplan_all on  --off

    check 约束

    create table teacher(
    id int not null primary key,
    name char(10),
    sex char(2) check(sex in ('',''))
    )
    
    alter table teacher
    add age int null
    
    alter table teacher 
    add constraint ck_age check (age>=0 and age<=100)
    
    alter table teacher
    drop constraint ck_age 
    View Code

     规则很少用 rule

    use test 
    go
    create table  teacher(
    id char(6) not null,
    name char(16) not null,
    nation char(10) not null,
    sex char(2) not null,--default ''
    price int constraint max_price check(price<=20)
    constraint sex default ''
    )
    
    alter table teacher
    add default '汉族' for nation
    
    alter table teacher
    add zzmm char(4) not null
    constraint name default '李明' --with values
    
    alter table teacher 
    drop constraint name
    
    create default mz_default as '汉族'
    exec sp_binddefault 'mz_default','stu.nation'
    
    exec sp_addtype sex,'cahr(2)','null'
    
    if exists(select name from sysobjects where name ='xb_default' and type ='D')
    BEGIN 
     EXEC sp_unbindefault 'sex'
     drop default xb_default
    END
    View Code
    create table book(
    书号 char(6),
    类型 char(20),
    价格 int 
    constraint max_price1 check (价格<=200)
    )
    
    use test 
    go 
    create rule type_rule as @类型 in('计算机','科普','文学')
    go 
    use test 
    go 
    exec sp_bindrule 'type_rule','book.类型'
    go
    
    exec sp_unbindrule 'book.类型'
    drop rule type_rule 
    alter table book
     add constraint booktype default 'new book' for 类型
    
     alter table book 
     drop constraint booktype 
    
     use test
     go
     create default day as 'getdate()'
     go
     
     alter table book 
     add 入学时间 datetime null
    
     exec sp_bindefault 'day','book.入学时间'
     exec sp_addtype today,'datetime','null'
     exec sp_bindefault 'day','today'
     alter table book 
     add 购书时间 today null 
    
     exec sp_unbindefault 'book.入学时间'
     exec sp_unbindefault 'today'
    View Code
    create table stu(id int not null constraint xh_pk primary key)
    
    alter table student 
    add constraint kcb_pk primary key clustered(stuid)
    
    alter table kcxx
    drop constraint kcb_pk
    
    create table table_name(
    id int not null constraint xh_pk primary key,
    name char(8) not null,
    IDCard int constraint sfzh_uk unique
    )
    
    alter table kcxx 
    add constraint cbh_uk unique nonclustered(id)
    
    alter table table_name 
    drop constraint kcb_uk
    
    create table xsda(
    学号 char(6) not null constraint xh_pk primary key,
    姓名 char(8) not null
    )
    
    create table xscj(
     学号 char(6) not null foreign key refeRences xsda(学号) 
    )
    
    alter table xscj
    add constraint kc_foreign foreign key(课程编号) references kcxx(课程编号)
    
    alter table xscj
    drop constraint kc_foreign
    View Code

    use test
    go
    declare @name char(6)
    set @name =(select top 1 name from xsda)
    select @name
    go

    select @@connections,@@rowcount,@@error,@@procid,@@remserver,@@servername,@@version,@@language,@@max_connections

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  • 原文地址:https://www.cnblogs.com/futengsheng/p/7900924.html
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