用户、角色和权限，多表查询(RBAC系统)

一，各个表格

1、用户表

CREATE TABLE `t_user` (

  `id` varchar(40) NOT NULL,

  `username` varchar(20) NOT NULL,

  PRIMARY KEY (`id`)

)

2、角色表

CREATE TABLE `t_role` (

  `id` int(11) NOT NULL AUTO_INCREMENT,

  `name` varchar(20) NOT NULL,

  `description` varchar(255) DEFAULT NULL,

  PRIMARY KEY (`id`)

)

3、权限表

CREATE TABLE `t_permission` (

  `id` int(11) NOT NULL AUTO_INCREMENT,

  `name` varchar(20) NOT NULL,

  `description` varchar(255) DEFAULT NULL,

  PRIMARY KEY (`id`)

)

4、用户角色关系表

CREATE TABLE `user_role` (

  `id` int(11) NOT NULL AUTO_INCREMENT,

  `user_id` varchar(40) NOT NULL,

  `role_id` int(11) NOT NULL,

  PRIMARY KEY (`id`),

  KEY `fk_user_role_t_role_1` (`role_id`),

  KEY `fk_user_role_t_user_1` (`user_id`),

  CONSTRAINT `fk_user_role_t_role_1` FOREIGN KEY (`role_id`) REFERENCES `t_role` (`id`) ON DELETE CASCADE ON UPDATE CASCADE,

  CONSTRAINT `fk_user_role_t_user_1` FOREIGN KEY (`user_id`) REFERENCES `t_user` (`id`) ON DELETE CASCADE ON UPDATE CASCADE

)

5、角色权限关系表

CREATE TABLE `role_permission` (

  `id` int(11) NOT NULL AUTO_INCREMENT,

  `role_id` int(11) NOT NULL,

  `permission_id` int(11) NOT NULL,

  PRIMARY KEY (`id`),

  KEY `fk_role_permission_t_permission_1` (`permission_id`),

  KEY `fk_role_permission_t_role_1` (`role_id`),

  CONSTRAINT `fk_role_permission_t_permission_1` FOREIGN KEY (`permission_id`) REFERENCES `t_permission` (`id`) ON DELETE CASCADE ON UPDATE CASCADE,

  CONSTRAINT `fk_role_permission_t_role_1` FOREIGN KEY (`role_id`) REFERENCES `t_role` (`id`) ON DELETE CASCADE ON UPDATE CASCADE

)

查询某用户的对应的角色

SELECT

u.id,u.username,r.`name` role_name

FROM

   t_user u,t_role r,user_role ur

WHERE

  u.username LIKE 'a%' AND u.id=ur.user_id AND ur.role_id=r.id;

查询拥有某权限的角色

SELECT p.`name`,r.`name`

FROM

t_permission p,role_permission rp,t_role r

WHERE

p.`name`='小说发布' AND p.id=rp.permission_id AND rp.role_id=r.id;