原来mysql不支持外键，要用InnoDB才可以..

原来一直用postgresql,最近接触到了mysql(5.0.20),它默认是MyISAM引擎，竟然不支持外键，后来才知道要用InnoDB引擎才能支持..

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create database test;
use test;
CREATE TABLE userinfo (
userid character(8) primary key,
temp character(8)

)Type=INNODB CHARACTER SET utf8;

CREATE TABLE commenttest(
userid character(8),
comment character varying(200),
foreign key(userid) references userinfo(userid) on delete cascade)
Type= INNODB CHARACTER SET utf8;


insert into userinfo values("06000017","aaaa");
insert into userinfo values("06000020","bbbb");

insert into commenttest values("06000017","cccccc");
insert into commenttest values("06000020","ddddd");