What is the difference between a stored procedure and a User-Defined Function (UDF)?

Stored procedures can execute database operations while UDFs cannot.

Returning a value is required in a stored procedure while returning values in a UDF is optional.

Values returned by a stored procedure can be used directly in a SQL statement while the values returned by a UDF cannot.

Multiple stored procedures can be called as part of a single executable statement while a single SQL statement can only call one UDF at a time.