Why is it recommended to avoid using "SELECT *" in SQL queries and list specific columns instead?

Using "SELECT *" in SQL queries can be inefficient and can lead to performance issues. It retrieves all columns from a table, even those that are not needed, which can result in unnecessary data transfer and processing. It is recommended to list specific columns in the SELECT statement to only retrieve the necessary data, improving query performance and reducing resource consumption. 

// Avoid using "SELECT *"
$query = "SELECT * FROM users";

// Instead, list specific columns
$query = "SELECT id, username, email FROM users";

Keywords

PHP SQL queries SELECT statement database optimization performance.

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