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  • sql常用语句

    select * from person
    select distinct name from person
    select * from person where name='huangcongcong'
    select * from person where year>1991
    select * from person order by id
    select * from person limit 5
    select * from person name like "%cong%"
    select * from person name like "[!hc]%"
    select * from person where name in('huangcongcong','huangbingbing')
    select * from person where name between 'huangbingbing' and 'huangcongcong'
    select name as xingming from person
    select * from person where name is null
    
    select * into person_back from person //mysql create table person_back (select * from person)
    
    insert into person (name,year) values('huangbingbing',1992)
    
    update person set year=1990 where name='huangbingbing'
    
    delete from person where name='huangcongcong'
    delete * from person
    delete from person
    
    create database my_db
    create table person
    (
        id int not null primary key check(id>0) auto_increment,
        name varchar(50) not null,
        address varchar(50) default 'shanghai',
        city varchar(50),
        foreign key (id) references order(id)
    )
    
    alter table person
    add unique (id)
    
    alter table person
    drop index id
    
    alter table person
    add primary key(id)
    
    alter table person
    drop primary key
    
    alter table person
    add foreign key (id) references order(id)
    
    alter table person
    drop foreign key
    
    alter table person
    add check(id>0)
    
    alter table person
    drop constraint check
    
    alter table person
    add constraint chk_person check(id>0)
    
    alter table person
    drop constraint chk_person
    
    alter table person
    alter city set default 'shenzhen'
    
    alter table person
    alter city drop default
    
    create index personIndex
    on person name
    
    alter table person
    drop index personIndex
    
    alter table person
    auto_increment=100
    
    create view personView
    select * from person
    select e_name from employees_china
    union
    select e_name from employees_usa
    
    select e_name from employees_china
    union all
    select e_name from employees_usa
    
    select persons.lastname, persons.firstname, orders.orderno
    from persons
    inner join orders
    on persons.id_p=orders.id_p
    order by persons.lastname
    
    select persons.lastname, persons.firstname, orders.orderno
    from persons
    left join orders
    on persons.id_p=orders.id_p
    order by persons.lastname
    
    
    select persons.lastname, persons.firstname, orders.orderno
    from persons
    right join orders
    on persons.id_p=orders.id_p
    order by persons.lastname
    
    select persons.lastname, persons.firstname, orders.orderno
    from persons
    full join orders
    on persons.id_p=orders.id_p
    order by persons.lastname
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  • 原文地址:https://www.cnblogs.com/huangcongcong/p/4004314.html
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