Linking the information back together is the key to this system. In the relational model, some bit of information was used as a "key", uniquely defining a particular record. When information was being collected about a user, information stored in the optional tables would be found by searching for this key. For instance, if the login name of a user is unique, addresses and phone numbers for that user would be recorded with the login name as its key. This simple "re-linking" of related data back into a single collection is something that traditional computer languages are not designed for.
Linking the information back together is the key to this system . In the relational model , some bit of information was used as a " key " , uniquely defining a particular record . When information was being collected about a user , information stored in the optional tables would be found by searching for this key . For instance , if the login name of a user is unique , addresses and phone numbers for that user would be recorded with the login name as its key . This simple " re - linking " of related data back into a single collection is something that traditional computer languages are not designed for .
How is data in an optional table accessed?
How is data in an optional table accessed ?
by searching for this key
by searching for this key