小组结果双重结果

I have been working on an application that runs the following query:

SELECT m.*, GROUP_CONCAT(g.title) as genres
FROM movie m
INNER JOIN genre_movie gm ON gm.movie_id = m.id
INNER JOIN genre g ON gm.genre_id = g.id
WHERE m.imdb_id = '454876'

When I run the query in my query browser or straight via SSH it returns the following results (example:)

In my PHP code I do the following to loop over the genres:

<?php $get =  mysql_query($query); // $query is the above query ?>
<?php $movieInfo = mysql_fetch_assoc($get); ?>
<?php $genres = explode(",", $movieInfo['genres']); ?>
<?php foreach ($genres as $genre) { ?>
    <li class="clear"><a><span class="value"><?php echo $genre; ?></span></a></li>
<?php } ?>

While the expected out is expected to be:

Drama, Adventure

The output is:

Drama, Drama, Drama, Adventure, Adventure, Adventure

Any idea why this is happening as I can't figure it out?

PS: I know a work-around would be to just add array_unique() when I explode the comma separated list of the genres but I want to know the root of the problem.

Basically when I run the query manually the genres show up fine, when it runs in the applications, it shows double while the rest of the info still shows just fine.

It seems like you have forgotten GROUP BY clause in SQL, due to which duplicate records are written.

Are you grouping by the proper movie id? It could be the reason that you are getting all genres grouped into one..

Solved it, problem was with the query, I forgot to GROUP BY:

SELECT m.*, GROUP_CONCAT(g.title) as genres
FROM movie m
INNER JOIN genre_movie gm ON gm.movie_id = m.id
INNER JOIN genre g ON gm.genre_id = g.id
WHERE m.imdb_id = '454876' GROUP BY m.id