查询数据库中所有的外键关系

用于查询数据库中所有外键关系的SQL语句如下：

select fk.name fkname , ftable.name ptablename, cn.name fkcol, rtable.name ftablename from sysforeignkeys
join sysobjects fk
on sysforeignkeys.constid = fk.id
join sysobjects ftable
on sysforeignkeys.fkeyid = ftable.id
join sysobjects rtable
on sysforeignkeys.rkeyid = rtable.id
join syscolumns cn
on sysforeignkeys.fkeyid = cn.id and sysforeignkeys.fkey = cn.colid