Group by not ordering by date correctly

Question

I have a query that lists theme parks by order of newest news story. The query is below.

$sql2 = 'SELECT tpf_news.park_id, name
FROM tpf_news
INNER JOIN tpf_parks ON tpf_news.park_id = tpf_parks.park_id GROUP BY name ORDER BY date DESC ' ;
$result2 = $pdo->query($sql2);

It was working fine until a theme park got more than one news story, the date being grouped is the older date not the newer so the theme park would remain at its original position, not jumping to the top of the list when it has a new story attached. How can I change the query so the grouping is done by most recent date?

If it's needed, below is the php foreach to display the data.

<?php foreach ($result2 as $row2): ?>
<h4>
<a class="bloglink" href="parknews.php?park_id=<?php echo $row2['park_id'];?>">
<?php echo $row2['name']; ?>
</a>
</h4>
<br>


<?php endforeach; ?>

Thanks

Answer 1

You are not selecting a date, so essentially it will use a "random" date. You could try selecting like this:

SELECT MAX(date) thedate, tpf_news.park_id, name
FROM tpf_news
INNER JOIN tpf_parks ON tpf_news.park_id = tpf_parks.park_id GROUP BY name ORDER BY thedate DESC

This selects the largest date within each group (name) and then orders by those dates.

Answer 2

I just worked it out:

$sql2 = 'SELECT tpf_news.park_id, name
FROM tpf_news
INNER JOIN tpf_parks ON tpf_news.park_id = tpf_parks.park_id GROUP BY name 

ORDER BY min(STR_TO_DATE(date, "%Y-%m-%d"))'

That seems to do the job. Thanks

Answer 3

SELECT tpf_news.park_id, name
FROM tpf_news
INNER JOIN tpf_parks ON tpf_news.park_id = tpf_parks.park_id 
GROUP BY name ORDER BY date DESC, **(AutoIncrement_Field)** DESC

Hope This Will Help..