MySQL连接3个表
我有3个表,我需要它们的组合才能看到所有列的组合(MySQL) 第一。表poi_ACL_权限MySQL连接3个表,mysql,join,null,Mysql,Join,Null,我有3个表,我需要它们的组合才能看到所有列的组合(MySQL) 第一。表poi_ACL_权限 ID permKey permName |1 |access_site |Access Site |2 |access_admin |Access Admin System |3 |publish_articles |Publish Articles |4 |publish_events |Publish E
ID permKey permName
|1 |access_site |Access Site
|2 |access_admin |Access Admin System
|3 |publish_articles |Publish Articles
|4 |publish_events |Publish Events
|5 |install_modules |Install Modules
|6 |post_comments |Post Comments
|7 |access_premium_content|Access Premium Content
|8 |limited_admin |Limited Admin
第二。表是poi_ACL_角色
ID roleName
| 1|Administrators
| 2|All Users
| 3|Authors
| 4|Premium Members
三,。表是poi\U ACL\U角色\U perms
ID roleID permID value addDate
| 16| 1| 2| 1|2009-03-02 17:13:21
| 17| 1| 7| 1|2009-03-02 17:13:21
| 18| 1| 1| 1|2009-03-02 17:13:21
| 19| 1| 5| 1|2009-03-02 17:13:21
| 20| 1| 8| 1|2009-03-02 17:13:21
| 21| 1| 6| 1|2009-03-02 17:13:21
| 22| 1| 3| 1|2009-03-02 17:13:21
| 23| 1| 4| 1|2009-03-02 17:13:21
| 24| 2| 1| 1|2009-03-02 17:13:31
| 25| 3| 7| 1|2009-03-02 17:13:38
| 26| 3| 8| 1|2009-03-02 17:13:38
| 27| 3| 6| 1|2009-03-02 17:13:38
| 28| 3| 3| 1|2009-03-02 17:13:38
| 29| 3| 4| 1|2009-03-02 17:13:38
| 30| 4| 7| 1|2009-03-02 17:13:42
| 31| 4| 6| 1|2009-03-02 17:13:42
我有一个疑问:
SELECT [roleName], [roleID], [value], [permID] AS RPID, [permKey], [permName], [poi_ACL_permissions].[ID] AS PID
FROM [poi_ACL_permissions]
LEFT OUTER JOIN [poi_ACL_role_perms]
ON [poi_ACL_permissions].[ID] = [poi_ACL_role_perms].[permID]
LEFT OUTER JOIN [poi_ACL_roles]
ON [poi_ACL_role_perms].[roleID] = [poi_ACL_roles].[ID]
ORDER BY [roleID], [permID] ASC
事实上,这给了我所需要的。。。(几乎;))结果是包含所有角色及其权限的数组。但是,我需要的也是空权限
现在:
但是,例如,所有用户应:
0 All Users 2 1 1 access_site
1 All Users 2 0 2 access_admin
2 All Users 2 0 3 publish_articles
3 All Users 2 0 4 publish_events
4 All Users 2 0 5 install_modules
5 All Users 2 0 6 post_comments
6 All Users 2 0 7 access_premium_content
7 All Users 2 0 8 limited_admin
等等
您能帮我使用SQL吗?在您的
角色
和权限
表之间使用交叉连接
,然后左键连接到角色(权限
表:
SELECT
r.roleName,
r.ID AS roleID,
COALESCE(rp.value, 0) AS value,
p.ID AS permissionID,
p.permKey,
p.permName
FROM poi_ACL_permissions p
CROSS JOIN poi_ACL_roles r
LEFT OUTER JOIN poi_ACL_role_perms rp
ON p.ID = rp.permID
AND r.ID = rp.roleID
ORDER BY r.ID, p.ID
另外,请注意表别名的使用(r
,p
,rp
)有助于提高查询的可读性
是的,但我正试图在mysql中这样做(“不知何故”):)这被标记为mysql,但查询看起来像SQL Server不,它是mysql,但我正在使用Dibi(),有趣的是,我正要添加完全相同的答案(即使使用相同的别名):P我唯一使用的是
coalesce
@MostyMostacho是的,coalesce
。。。如果可能,最好保持ANSI标准。
SELECT
r.roleName,
r.ID AS roleID,
COALESCE(rp.value, 0) AS value,
p.ID AS permissionID,
p.permKey,
p.permName
FROM poi_ACL_permissions p
CROSS JOIN poi_ACL_roles r
LEFT OUTER JOIN poi_ACL_role_perms rp
ON p.ID = rp.permID
AND r.ID = rp.roleID
ORDER BY r.ID, p.ID