PHP/MySQL group results by column
18,286
Solution 1
Like mluebke
commented, using GROUP means that you only get one result for each category. Based on the list you gave as an example, I think you want something like this:
$sql = "SELECT * FROM products WHERE category IN (10,120,150,500) GROUP BY category ORDER BY category, id";
$res = mysql_query($sql);
$list = array();
while ($r = mysql_fetch_object($res)) {
$list[$r->category][$r->id]['name'] = $r->name;
$list[$r->category][$r->id]['whatever'] = $r->whatever;
// etc
}
And then loop through the array. Example:
foreach ($list as $category => $products) {
echo '<h1>' . $category . '</h1>';
foreach ($products as $productId => $productInfo) {
echo 'Product ' . $productId . ': ' . $productInfo['name'];
// etc
}
}
Solution 2
Nope, I think your solution is the best for this problem. It seems that what's important for you is the output later on, so you should stick with your approach.
Comments
-
Adam Kiss almost 2 years
in order to keep as few SQL statements as possible, I want to do select set from MySQL:
SELECT * FROM products WHERE category IN (10,120,150,500) ORDER BY category,id;
Now, I have list of products in following manner:
CATEGORY - product 1 - product 2 CATEGORY 2 - product 37 ...
What's the best and most efficent way to process MySQL result?
I thought something like (pseudo PHP)
foreach ($product = fetch__assoc($result)){ $products[$category][] = $product; }
and then when outputting it, do foreach loop:
foreach($categories as $category){ foreach($products[$category] as $product){ $output; } }
Is this the best, or is something magical like
mysql_use_groupby
or something?