How to Efficiently Count Rows in a Database Table Using SQL and PHP?

Getting the Count Using SELECT COUNT(*)

Instead of selecting all rows or a specific column, you may want to simply retrieve the count of rows in a specific table. Here's how you can do that using the SELECT COUNT(*) query:

Query Structure:

SELECT COUNT(*) AS count FROM cars

Retrieving the Count Value in PHP:

Since the result of the COUNT(*) query is a scalar value, representing the count of rows, you can retrieve it using the following code:

$count = $mysqli->query("SELECT COUNT(*) AS cnt FROM cars")->fetch_object()->cnt;

In this case, we avoid using the reserved word "count" for the column name by aliasing it as "cnt". By calling the fetch_object() method on the result object, we retrieve an anonymous object with a single property named "cnt". The value of this property represents the count of rows in the "cars" table.

Note: It's not recommended to use the keywords "count" or "cnt" as column names in SQL, as they are reserved words.

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