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POJoining votes between tables and getting a percentage
 

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    <p>I have been working at this one for an hour. I have tried several different joins, and subqueries with no luck. Here is the situation.</p> <p>Two tables. One with an main index, and one a listing of votes from users. I want to determine how many votes a particular user is leaving for another user (easy)... THEN figuring out the percentage of the total votes and sorting by that (hard).</p> <p>Table 1 has columns: post_id, poster_id Table 2 has columns: post_id, voter_id, vote</p> <p>The post_id is correlated between the two tables. A simple query like this will get you an output showing the total votes 1 user has left another user... then sorts showing who has left the most votes for another.</p> <pre><code>SELECT poster_id, voter_id, count(*) AS votes FROM table_1, table_2 WHERE table_1.post_id = table_2.post_id GROUP BY poster_id, voter_id ORDER BY votes DESC </code></pre> <p>That works great... but I want to see who is leaving the most votes as a percentage of the users total votes. So I need to ALSO get the total votes a "poster_id" has, then divide the current number into a percentage... then sort into that percentage. Output should be something like:</p> <pre><code>poster_id | voter_id | votes | vote_total | percent ---------------------------------------------------- 1 | 3 | 10 | 10 | 100% 3 | 1 | 15 | 25 | 60% 2 | 1 | 3 | 6 | 50% 2 | 3 | 2 | 6 | 33% 3 | 2 | 5 | 25 | 20% 2 | 4 | 1 | 6 | 17% </code></pre> <p>etc.</p> <p>Basically voter #3 is responsible for 100% of poster #1's votes. Poster #3 got 60% of its votes from voter #1... etc.</p> <p>We're trying to find out if there is a particular user giving someone more votes (as a percentage) than other users to try and find potential abuses.</p> <p>I thought a RIGHT JOIN would work, but it is not working out.</p> <pre><code>SELECT t1.poster_id, t1.voter_id, count(*) AS votes, count(t3.*) AS votes_total, votes / votes_total AS percentage FROM (table_1 t1, table_2 t2) RIGHT JOIN (table_1 t3, table_2 t4) ON (t3.post_id = t4.post_id AND t3.poster_id = t1.poster_id) WHERE t1.post_id = t2.post_id GROUP BY t1.poster_id, t2.voter_id ORDER BY percentage DESC </code></pre> <p>Basically runs forever and doesn't return anything. I typed that query from memory, and doesn't exactly represent the real table names. Any points in the right direction would help. Inner join perhaps?</p>
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