Following are the main differences between functions and procedures:
| Functions | Procedures |
|---|---|
| A function has a return type and returns a value. | A procedure does not have a return type. But it returns values using the OUT parameters. |
| You cannot use a function with Data Manipulation queries. Only Select queries are allowed in functions. | You can use DML queries such as insert, update, select etc… with procedures. |
| A function does not allow output parameters | A procedure allows both input and output parameters. |
| You cannot manage transactions inside a function. | You can manage transactions inside a procedure. |
| You cannot call stored procedures from a function | You can call a function from a stored procedure. |
| You can call a function using a select statement. | You cannot call a procedure using select statements. |