differences between procedure and function and routine?

Question

in mysql database context, what is the difference among these 3 terms?

stored procedure,stored routine,stored function.

p.s. build-in functions like those date time functions, (weekday()) are considered as what?

thanks in advance!

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.