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POMysql Left join multiple 1 to many tables
 

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    <p>I am trying to get the following data from 3/4 tables in 1 <code>Mysql query</code>, wondering if it is possible ? The tables are</p> <pre><code>TOPIC topicid (FK)(PK) groupid topic user LIKED likeid topicid (FK) user COMMENT commentid (PK) topicid (FK) comment user </code></pre> <p>I write my topics and store in TOPIC Table with unique topicid. I group each topic using groupid. Other tables may have 0 or more data per topicid.</p> <p>I am trying to get each topic for a particular group and also get other datas from the concerned Tables. I checked <a href="https://stackoverflow.com/questions/4650914/how-to-left-join-multiple-one-to-many-tables-in-mysql">How to left join multiple one to many tables in mysql?</a> and got few idea but that is for the count while I wanted to get details from that table (users who like), and (user and their comment).</p> <p>I have tried</p> <pre><code>SELECT t.topicid, topic, group_concat(DISTINCT likeid,l.user SEPARATOR '|'), group_concat(DISTINCT commentid,comment,c.user SEPARATOR '|') AS comments FROM TOPIC t LEFT JOIN LIKE l ON l.topicid = t.topicid LEFT JOIN COMMENT c ON c.topicid = t.topicid WHERE t.groupid='some_value' GROUP BY t.topicid </code></pre> <p>While this works partly e.g. I do get the details but only if there is one topic in a group. If there are 2 or more topics in a group then the <code>concat</code> details are stored in the first record only and the later topics show no likes and comments. </p> <p>Can someone please help me to correct this or any particular <code>Mysql function</code> I am missing</p>
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    1. USCommunity
    1. USjahajee.com
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    1. COI'm confused. You are joining and grouping by `topicid`. Then you are complaining that multiple topics don't get multiple values when they are in a group. Do you want to sort by groupid?
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    2. COCould you make a sqlfiddle with sample data, and show what the desired result should be?
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      1. USBarmar
    3. CO@Barmar I tried sqlfiddle at [link](http://sqlfiddle.com/#!2/9ab57/1/0) .
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