dongqiao6730 2015-08-02 23:04
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从连接表中获取行数[关闭]

I am pulling out rows from my database which will also show the number of responses to the post. I am able to grab the rows but need to do a count on the posts from a join table which takes the post_id and comment_id - I am not sure on how to approach this or if it is even doable?

function build_forum_featured(){    

    global $dbc;

    $q = "SELECT u.user_id, u.first_name, u.last_name, f.post_created, f.post_id, f.post_title, j.id 
             FROM users AS u
             INNER JOIN user_post_join AS j ON u.user_id = j.user_id
             INNER JOIN forum_post AS f ON f.post_id = j.post_id
             WHERE featured_post = 2
             ORDER BY post_created ASC
    ";  

    $r = mysqli_query ($dbc, $q); // Run the query.



    // FETCH AND PRINT ALL THE RECORDS
    while ($row = mysqli_fetch_array($r)) {

    echo '
    <div class="post">
        <div class="col-group-2">
            <a href="post_view.php?post_id='.$row["post_id"].'"><h3>'.$row["post_title"]. '</h3></a>
            <p>By: <a href="user_view.php?id=' . $row["user_id"] . '">'.$row["first_name"] . ' ' .$row["last_name"]. '</a> on: ' .date('d-m-Y', strtotime($row["post_created"])). '</p>
        </div>

        <div class="col-group-2">
            <div class="post_count">
                <h3  class="answer">0</h3> // count goes here!
                <p class="answer">Responses</p>
            </div>
        </div>  
    </div>
    ';

    } 

Essentially what I a trykgi to do is reference the join table and check to see the post_id and how many comments are associated to that post. so I have a table called comment_post_join which takes the post_id and the comment_id and just adds rows.

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1条回答 默认 最新

  • dqx24298 2015-08-02 23:24
    关注

    add a count(*) to the list of your columns to select and add a group by user_id, post_id at the end of your statement...

    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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