Software Architect's Handbook

Data coupling

Data coupling occurs when two modules share some data which are just primitive data values. It is another low type of coupling. A common type of data coupling is when a module calls a method on another module, and inputs and outputs are shared in the form of method parameters and the return value.

When two modules need to interact, this is a common and acceptable type of coupling. Unlike stamp collecting, where some of the values in the shared composite data structure may not be used, all of the parameters in data coupling are used. If any parameters are not needed, they should be removed.