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    <blockquote> <p>The query will be required to run on every page the user loads and we have over 30,000 permissions, and 3,000 roles. I am just trying <strong>very hard</strong> to keep my number of queries to a minimum. We also host our 7 sites on a server in our office, and the server doesn't seem to be capable of handling the amount of traffic we generate (unfortunately I have no control over this)</p> </blockquote> <p>I see that your intentions are good, but let me tell you this: </p> <p>The "number of queries" is not the right way to measure your site's performance. </p> <p>Many times 2 simple queries use less resources than 1 complex. </p> <p>Also there are other ways to speed up your sites: </p> <ul> <li>Assess if you really need all those roles and permissions loaded on each request. Maybe querying for only the role/permission needed is enough.</li> <li>Have proper indexes </li> <li>Utilize caching techniques to reduce the load (site content)</li> </ul> <p>So finally, I tried to come up with query to satisfy what was asked: </p> <pre><code>select * from ( select ur.role_id, p.* from user_roles ur left join permissions_role pr on ur.role_id = pr.role_id left join permissions p on p.id = pr.perm_id where ur.user_id = '$userid' union all select null as role_id, p.* from permissions_user pu join permissions p on p.id = pu.perm_id where pu.user_id = '$userid' ) sub group by ifnull(name,role_id) -- group by to eliminate duplicates </code></pre> <p>But this is not good on performance. You are much better off with 2 queries: 1st to get all permissions for user</p> <pre><code>select p.* from permissions p join permissions_role pr on pr.perm_id = p.id join user_roles ur on ur.role_id = pr.role_id and ur.user_id = '$userid' union select p.* from permissions p join permissions_user pu on pu.perm_id = p.id and pu.user_id = '$userid'; </code></pre> <p>and 2nd to get all roles. </p>
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    1. COThank you for your help. FYI for others who view the question... I also posted an answer which reflects the final working queries and supporting code to demonstrate how the queries are used.
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