Editing Composite key (section)

== Advantages ==
Composite keys have advantages similar to that of a [[natural key]] as it is often composed of multiple natural key attributes.
=== Storage ===
Composite keys use less disk space as compared to defining a [[surrogate key]] column, this is because the composite key already exists as attributes in the table and does not need to be defined in the table just for the purpose of unique identification. This simplifies the table and also saves space.

=== Easier to implement and use ===
Composite keys are easy to implement in a [[database schema]] as their component parts are already named items in the database. When they are also natural keys, they are often intuitive for real world scenarios. They are often used when a non-composite key does not always uniquely identify a record. For example, a personal name may often, but not always, be unique in a given database, and some other field such as date of birth may be added to make uniqueness much more probable.