Question

Okay, so I already have a script to let users enter tags but I want to let users enter multiple tags that are separated by a comma for example, (html, css, php) and store each tag in the database.

Is there a tutorial that can show me how to do this or can someone give me a couple of examples that i can work from.

Thanks

Answer 1

Assuming a schema like this:

• Post (id, author_id, post_date, post_text);
• Tag (id, tag_name);
• Post Tag (id, post_id, tag_id).

The Post Tag table is what’s called a join table for the many-to-many relationship from Post to Tag (because a Post can have multiple Tags and a Tag can be used on multiple Posts).

The user enters a list of tags separated by commas into an input field:

$tags = array_unique(array_map(explode(',', $POST['tags']), 'trim'));

and you have an array of tags the user entered. You may want to sanitize them further, like only allowing certain characters and/or converting them to lowercase.

Then your code becomes:

$post_id = ...
foreach ($tats as $tag) {
  $tag = mysql_real_escape_string($tag);
  $sql = <<<END
INSERT INTO PostTag (post_id, tag_id)
VALUES ($post_id, (SELECT id FROM Tag WHERE tag_name = '$tag'))
END;
  mysql_query($sql);
}