In what scenarios would using SQL for string manipulation be more efficient than using PHP functions like preg_replace()?

Using SQL for string manipulation can be more efficient when you need to manipulate large amounts of data that are stored in a database. This is because SQL is optimized for handling large datasets and can perform string manipulation directly on the database server, reducing the amount of data that needs to be transferred between the server and the application. In contrast, using PHP functions like preg_replace() would require retrieving the data from the database, manipulating it in PHP, and then sending it back to the database, which can be slower and less efficient.

// Example of using SQL for string manipulation
$query = "UPDATE table SET column = REPLACE(column, 'old_string', 'new_string') WHERE condition";
// Execute the query using your database connection