My database has 3 tables i wish to access in the select query but I cannot seem to get it to work. Selecting from 2 tables works fine so I know everything else is working apart from my code for selecting from 3 tables. My database has been created on PHPmyadmin
The Tables are as follows:
forum_replies
forum_topics
users
This is the code I have tried to use and shows the fields I wish to select:
$queryreply = "SELECT forum_replies.reply_id, forum_replies.topic_id, forum_replies.user_id,
forum_replies.reply_text, forum_replies.reply_date, users.user_id, users.username
forum_topics.topic_id,forum_topics.topic_title, forum_topics.topic_date
FROM forum_replies
JOIN forum_topics
ON forum_replies.topic_id = forum_topics.topic_id
JOIN users
ON forum_replies.user_id = users.user_id
";
$result = mysql_query($queryreply) or die (mysql_error());
$row = mysql_fetch_array($result);
Example in code would be appreciated. Thanks
You miss the ,
after users.username
..
SELECT forum_replies.reply_id, forum_replies.topic_id, forum_replies.user_id,
forum_replies.reply_text, forum_replies.reply_date, users.user_id, users.username,
forum_topics.topic_id,forum_topics.topic_title, forum_topics.topic_date
Use this query:
SELECT a.reply_text, a.reply_date, b.topic_title, c.username
FROM forum_replies a
LEFT JOIN forum_topics b ON a.topic_id=b.topic_id
LEFT JOIN users c ON a.user_id=c.user_id
// apply WHERE, ORDER, GROUP if needed
Apart from syntax errors, you should use LEFT JOIN
and table alias in your case.
To show also the topic creator's username, you can adjust the query to the following:
SELECT a.reply_text, a.reply_date, b.topic_title, c.username AS reply_user, (SELECT username FROM users WHERE user_id=b.user_id) AS topic_creator
FROM forum_replies a
LEFT JOIN forum_topics b ON a.topic_id=b.topic_id
LEFT JOIN users c ON a.user_id=c.user_id
// apply WHERE, ORDER, GROUP if needed
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