mysql数据库学习――4，完整性约束_MySQL

create table feng(teamno int not null,playerno int not null,pision char(6) not null,primary key(teamno))create table feng(teamno int not null primary key ,playerno int not null,pision char(6) not null,)

create table feng(teamno int not null,playerno int not null,pision char(6) not null,primary key(teamno，playerno))

create table feng(teamno int not null primary key ,playerno int not null,pision char(6) not null,unique(playerno))create table feng(teamno int not null primary key ,playerno int not null,pision char(6) not null,unique(playerno，pision))

on update restricton delete  restrictcreate table feng(teamno int not null primary key ,playerno int not null,pision char(6) not null,foreign key（pision）references othertable   （column）on update restrictunique(playerno))check完整性约束create  table players (playerno int not null, sex   char(1) not null,         check (sex in (&#39;m&#39;,&#39;f&#39;)))create  table players (playerno int not null,birth_date  date, sex   char(1) not null,         check (sex in (&#39;m&#39;,&#39;f&#39;))joined smallint not null,             check (year(birth_date)<joined),             check (joined<1880),)create  table players (playerno int not null,birth_date  date, sex   char(1) not null,          check (sex in (select sex from wholetab))