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    <p>Change your query to this:</p> <pre><code> SELECT u.user_id, us.orig_posts_count, us.sugg_posts_count, IF(us.user_id='4', 'posterview', COUNT(CASE WHEN p.sugg_by='2' AND (p.private='0' OR pv.post_id IS NOT NULL) THEN 1 ELSE NULL END)) AS display_orig_posts_count, IF(us.user_id='4', 'posterview', COUNT(CASE WHEN p.sugg_by&lt;&gt;'2' AND (p.private='0' OR pv.post_id IS NOT NULL) THEN 1 ELSE NULL END)) AS display_sugg_posts_count FROM users AS u JOIN user_stats AS us ON u.user_id=us.user_id JOIN posts AS p ON p.user_id=us.user_id LEFT JOIN private AS pv ON pv.post_id=p.post_id AND pv.authorized_user_id='4' WHERE u.user_id='2' GROUP BY u.user_id, us.orig_posts_count, us.sugg_posts_count </code></pre> <p><strong>DETAILED EXPLANATION</strong></p> <p>In your first query, the following posts are being counted (with reasons):</p> <pre><code>display_orig_posts_count = 3: post_id=2: pv.post_id is not null (fails ISNULL() check) post_id=4: pv.post_id is not null (fails ISNULL() check) post_id=6: p.private='0' (fails p.private='1' check) display_sugg_posts_count = 5: post_id=2: pv.post_id is not null (fails ISNULL() check) post_id=3: p.sugg_by='2' (fails p.sugg_by&lt;&gt;'2' check) post_id=4: pv.post_id is not null (fails ISNULL() check) post_id=5: p.sugg_by='2' (fails p.sugg_by&lt;&gt;'2' check) post_id=6: p.private='0' (fails p.private='1' check) </code></pre> <p>In your second query, the following posts are being counted (with reasons):</p> <pre><code>display_orig_posts_count = 1: post_id=2: pv.post_id is not null (fails ISNULL() check) display_sugg_posts_count = 3: post_id=2: pv.post_id is not null (fails ISNULL() check) post_id=3: p.sugg_by='2' (fails p.sugg_by&lt;&gt;'2' check) post_id=5: p.sugg_by='2' (fails p.sugg_by&lt;&gt;'2' check)' </code></pre> <p>In your third query, the following posts are being counted (with reasons):</p> <pre><code>display_orig_posts_count = 2: post_id=4: pv.post_id is not null (fails ISNULL() check) post_id=6: p.private='0' (fails p.private='1' check) display_sugg_posts_count = 2: post_id=4: pv.post_id is not null (fails ISNULL() check) post_id=6: p.private='0' (fails p.private='1' check) </code></pre> <p>What do we want to be counted:</p> <pre><code>display_orig_posts_count = 1: post_id=2: because p.sugg_by=2, p.private=1 AND (is_authorized) display_sugg_posts_count = 3: post_id=4: because p.sugg_by&lt;&gt;'2', p.private=1 AND (is_authorized) post_id=6: because p.sugg_by&lt;&gt;'2', p.private=0 </code></pre> <p>So let's clean this up:</p> <ol> <li><p><strong>Strip out <code>p.user_id='2'</code> from `CASE1 statements</strong></p> <p>This is always true anyway, because you're limiting posts to only those posts with <code>user_id='2'</code> by virtue of your <code>JOIN</code> statements.</p></li> <li><p><strong>Use affirmative checks</strong></p> <p>In the case of <code>display_orig_posts_count</code>, we <em>want</em> certain things. Rather than trying to filter out the things we don't want, let's explicitly look for the things we <em>do</em> want:</p> <pre><code> COUNT(CASE WHEN p.sugg_by='2' AND (p.private='0' OR pv.post_id IS NOT NULL) THEN 1 ELSE NULL ) </code></pre> <p>In the case of <code>display_sugg_posts_count</code>, let's again look for those things explicitly:</p> <pre><code> COUNT(CASE WHEN p.sugg_by&lt;&gt;'2' AND (p.private='0' OR pv.post_id IS NOT NULL) THEN 1 ELSE NULL ) </code></pre></li> <li><p><strong>Use <code>GROUP BY</code> when using aggregation functions</strong></p> <p>You shouldn't need <code>LIMIT 1</code>, either, if you're properly grouping aggregated functions. Only one row should ever be returned for each user.</p></li> </ol>
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    1. COBy far the best detailed explanation. Quick note: Does it matter if I drop the `us.orig_posts_count, us.sugg_posts_count` from the `GROUP BY u.user_id, us.orig_posts_count, us.sugg_posts_count` and instead do `GROUP BY u.user_id`? Thank you hrunting!
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    2. COIt doesn't matter in this case because there's only one `orig_posts_count/sugg_posts_count` pair per `user_id` value. In fact, you don't actually need to group by anything in this query because the query should always return only one row per `user_id` value anyway. Still, I do it to be explicit about what is intended, and some SQL systems won't let you use aggregate functions (like `COUNT`, `MAX`, `AVG`, etc.) with non-aggregated fields unless you group by each non-aggregated field.
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    3. COExcellent. Thank you!
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