我有3个表，我需要它们的组合来查看所有列的组合（MySQL）。
1.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 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_roles
ID roleName
| 1|Administrators
| 2|All Users
| 3|Authors
| 4|Premium Members
第三，表是poi_ACL_role_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
我有这样的疑问：
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；））结果是具有所有角色及其权限的数组。但是，我需要的也是空权限。
现在：
0 Administrators 1 1 1 access_site Access Site 1
1 Administrators 1 1 2 access_admin Access Admin System 2
2 Administrators 1 1 3 publish_articles Publish Articles 3
3 Administrators 1 1 4 publish_events Publish Events 4
4 Administrators 1 1 5 install_modules Install Modules 5
5 Administrators 1 1 6 post_comments Post Comments 6
6 Administrators 1 1 7 access_premium_content Access Premium Content 7
7 Administrators 1 1 8 limited_admin Limited Admin 8
8 All Users 2 1 1 access_site Access Site 1
9 Authors 3 1 3 publish_articles Publish Articles 3
10 Authors 3 1 4 publish_events Publish Events 4
11 Authors 3 1 6 post_comments Post Comments 6
12 Authors 3 1 7 access_premium_content Access Premium Content 7
13 Authors 3 1 8 limited_admin Limited Admin 8
14 Premium Memb. 4 1 6 post_comments Post Comments 6
15 Premium Memb. 4 1 7 access_premium_content Access Premium Content 7
但是，例如，所有用户都应该：
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。。。
你能帮我查一下SQL吗？
最佳答案
在您的CROSS JOIN和role表之间使用permission，然后左键加入role_permission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）有助于查询的可读性。SQL Fiddle