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Query Multiple Tables Jointly in MySQL
How To Query Multiple Tables Jointly in MySQL?
✍: FYIcenter.com
If you want to query information stored in multiple tables, you can use the SELECT statement with a WHERE condition to make an inner join. Assuming that you have 3 tables in a forum system: "users" for user profile, "forums" for forums information, and "posts" for postings, you can query all postings from a single user with a script as shown below:
<?php include "mysql_connection.php"; $userID = 101; $sql = "SELECT posts.subject, posts.time, users.name, . " forums.title" . " FROM posts, users, forums" . " WHERE posts.userID = ".$userID . " AND posts.userID = users.id" . " AND posts.forumID = forums.id"; $rs = mysql_query($sql, $con); while ($row = mysql_fetch_assoc($rs)) { print($row['subject'].", ".$row['time'].", " .$row['name'].", ".$row['title']."\n"); } mysql_free_result($rs); mysql_close($con); ?>
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2017-06-23, 2437👍, 0💬
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