What's the differences between stored procedures, functions and routines?

Question

In MySQL database context, what is the difference among these 3 terms:

• stored procedure
• stored function
• stored routine

Also the build-in functions like those date time functions (e.g. WEEKDAY() etc) are considered as what?

Answer 1

Google is your friend. The first match for "mysql routine function procedure" is this: http://dev.mysql.com/doc/refman/5.0/en/stored-routines-syntax.html

A quick summary:

A stored routine is either a procedure or a function.

A procedure is invoked using a CALL statement and can only pass back values using output variables.

A function can be called from inside a statement just like any other function and can return a scalar value.