How can the use of SELECT * in a SQL query impact the performance of a PHP script?

Using SELECT * in a SQL query can impact the performance of a PHP script because it retrieves all columns from a table, even if they are not needed. This can lead to unnecessary data transfer between the database and the PHP script, resulting in slower execution times. To improve performance, it is recommended to explicitly specify only the columns that are needed in the SELECT statement.

// Specify only the necessary columns in the SQL query
$sql = "SELECT column1, column2 FROM table_name WHERE condition";

// Execute the query and fetch the results
$result = mysqli_query($connection, $sql);

// Process the results as needed
while ($row = mysqli_fetch_assoc($result)) {
    // Do something with the data
}