How to Retrieve a Single Value from a MySQL COUNT(*) Query in PHP?

Retrieving Single Value from a MySQL Count Query in PHP

Problem:

You are trying to retrieve the count of rows from a MySQL table using the SELECT COUNT(*) query, but you are unable to obtain a single output value from the result.

Solution:

To retrieve the single value from the count query, you need to alias the aggregate function using the AS keyword. This creates a placeholder name for the result, which you can then use to fetch the actual value.

Code:

$result = mysql_query("SELECT COUNT(*) AS total FROM Students");
$data = mysql_fetch_assoc($result);
echo $data['total'];

In this code, the total alias is assigned to the COUNT(*) aggregate function. When you fetch the data using mysql_fetch_assoc(), it returns an associative array where the key is the alias and the value is the corresponding result. By accessing the total key in the array, you can retrieve the single output value.

Note that mysql_query() and mysql_fetch_assoc() are deprecated functions in PHP 7 and later. For modern PHP versions, use PDO or MySQLi extension for database operations instead.

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