How to Retrieve Aggregate Values (e.g., COUNT(*)) from MySQL Queries in PHP?

Retrieving Aggregate Values from MySQL Queries in PHP

When working with aggregate functions like COUNT(*), it's crucial to understand how to extract the result as a single value.

In PHP, executing a query like SELECT COUNT(*) FROM Students; returns a resource handle representing the result set. To access the count, we need to alias the aggregated expression using the AS keyword.

$result = mysql_query("SELECT COUNT(*) AS total FROM Students;");

With the alias set, we can fetch the result using mysql_fetch_assoc() or mysql_fetch_row(). However, mysql_fetch_assoc() is preferred since it returns an associative array where the alias is used as the key.

$data = mysql_fetch_assoc($result);
echo $data['total'];

This code assigns the total count to the $data array and prints the count using the alias as the key.

Note: Remember to use mysqli functions (e.g., mysqli_query(), mysqli_fetch_assoc()) instead of mysql functions for better security and compatibility.

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