6. Document-Oriented Database
For example here's a document:
FirstName="Bob", Address="5 Oak St.", Hobby="sailing".
Another document could be:
FirstName="Jonathan", Address="15 Wanamassa Point Road", Children=("Michael,
10", "Jennifer,8", "Samantha,5", "Elena,2").
Notice that both documents have some similar information and some different - but
unlike a relational database where each record would have the same set of fields and
unused fields might be kept empty, there are no empty 'fields' in either document
(record) in this case. This system allows information to be added any time without
wasting storage space for "empty fields" as in relational databases.
From Wikipedia Document-Oriented Database
http://en.wikipedia.org/wiki/Document-oriented_database
11. set profile:1:name z.ohnami
set profile:1:blood A
set profile:1:age 30
set profile:2:name y.konami
set profile:2:blood C++
set profile:2:height 140