How Can I Efficiently Count Rows in a Database Using SELECT COUNT(*) in PHP?

*Optimizing database row count statistics: Best practice for SELECT COUNT() function**

The traditional method usually executes the query first and then uses the num_rows() function to count the number of rows. However, using the SELECT COUNT(*) function allows you to directly obtain the number of rows, significantly improving code efficiency.

This method avoids unnecessary database data retrieval and only focuses on counting rows. The SELECT COUNT(*) as count FROM cars syntax you proposed is correct, but it is recommended to avoid using reserved words such as "count" as column aliases to avoid conflicts.

To get the results of COUNT(*) in PHP, you can use the fetch_object() method of querying the results. This method returns an object whose property names correspond to column aliases. In this case, you can use $count->cnt to get the number of rows:

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

With this approach, you can efficiently determine the number of rows without having to query and process the entire data set.

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