How to Efficiently Retrieve and Use SELECT COUNT(*) Results in PHP?

SELECT COUNT(*) AS Count: Practical Application

In database queries, the SELECT COUNT(*) syntax retrieves the total number of rows in a table. This count is often used as a conditional check or for pagination purposes. However, a common question arises: how to access and use this count value in PHP.

Problem:

Instead of selecting all rows or specific columns, the goal is to efficiently retrieve only the row count. Using SELECT COUNT(*) as count FROM cars does not provide a straightforward way to access the resulting count.

Solution:

To access the count obtained from SELECT COUNT(*), it is not recommended to use reserved words like "count" for naming. Instead, consider using an alternative name such as "cnt". Note that this function returns a scalar value, indicating that only a single value is expected back.

The following PHP code illustrates how to retrieve the count:

$count = $mysqli->query("select count(*) as cnt from cars")->fetch_object()->cnt;

In this example, the fetch_object()->cnt call returns the count assigned to the "cnt" alias in the query result. You can then use the $count variable to perform conditional checks or other logic based on the row count in the "cars" table.

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