在PHP中按ID显示总和[重复]

Question

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I have a table table_log filled with logs with different IDs but some of those logs have the same ID. I have to get the sum of column counter of those with the same ID id then display the results a column total_count. This is my query:

SELECT id, SUM(counter) AS total_count FROM table_log GROUP BY id

I have to display this in a table column using PHP. This is what I have:

$sql = "SELECT id, SUM(counter) AS total_count FROM table_log GROUP BY id";
$row = mysql_fetch_assoc($sql);
$sum = $row['total_count'];
$data .= "<td style='width: 200px;' align=center >". $sum ."</td>";

It's not appearing in the table. What should I input instead?

EDIT : I didn't choose to use this. The company did.

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Answer 1

Firstly - mysql_* functions are deprecated. Avoid them as much as possible.

Secondly, you need to run the query first, before you can fetch the results.

$conn = mysqli_connect("localhost", "root", "", "db"); //connection string
$q = mysqli_query($conn, $sql);
$row = mysqli_fetch_assoc($q);

Then it'll work.