php - Duplicating the result when adding two tables -


i'm working on website categories. when user clicks link goes categories.php?id=$id

this working. since i'm using fk, have use code:

$result = mysql_query( "select * post_posts, post_cat post_cat = $id" ) or die("select error: ".mysql_error()); $num_rows = mysql_num_rows($result); if ($result) {     while ($row = mysql_fetch_array($result)) {         $_session['idpost_posts']=$row['idpost_posts'];          echo '<div id="single-post" class="slidingdiv">             <div id="title">' . $row['post_header'] . '</div>             <div id="image"><img src="' . $row['post_thumb'] . '" width="300" height="200"></div>             <div id="text">' . substr($row['post_content'], 0, 500) . '<a href="page.php?id=' . $row['idpost_posts'] . '"> les mer...</a>' . '      </div>             <div id="author">' . "skrevet: " . date('j. f y ', strtotime($row['post_date'])) . ' | <a href="user.php?id=' . $row['idpost_users'] . '">' . $row['user_name'] . '</a></div>              <div id="post-divider"></div>             </div>';     }     }

the code working, stated earlier, shows same row 5 times. idea how fix this?

edit: i'm using now, , shows 2 rows now, better:

$result = mysql_query( "select distinct idpost_posts, post_content, post_header, post_thumb, post_date, idpost_users, user_name post_posts, post_cat, post_users post_cat = $id" )         or die("select error: ".mysql_error());         $num_rows = mysql_num_rows($result);if ($result) {while ($row = mysql_fetch_array($result)) {         $_session['idpost_posts']=$row['idpost_posts'];          echo '<div id="single-post" class="slidingdiv">             <div id="title">' . $row['post_header'] . '</div>             <div id="image"><img src="' . $row['post_thumb'] . '" width="300" height="200"></div>             <div id="text">' . substr($row['post_content'], 0, 500) . '<a href="page.php?id=' . $row['idpost_posts'] . '"> les mer...</a>' . '      </div>             <div id="author">' . "skrevet: " . date('j. f y ', strtotime($row['post_date'])) . ' | <a href="user.php?id=' . $row['idpost_users'] . '">' . $row['user_name'] . '</a></div>              <div id="post-divider"></div>             </div>';

your sql "select * post_posts, post_cat post_cat = $id" performing cross cartesian join(you not want this) between post_posts , post_cat table. should defining columns should joining 2 table so.

select * post_posts, post_cat post_posts.<primary key col name> = post_cat.<foreign key col name> , post_cat = $id

where replacing <> columns define foreign key relationship in each table. if want more detailed need post foreign key constraint details including column applied , column references in other table.


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