A current database is a conventional
database
In computing, a database is an organized collection of data stored and accessed electronically. Small databases can be stored on a file system, while large databases are hosted on computer clusters or cloud storage. The design of databases spa ...
that stores
data
In the pursuit of knowledge, data (; ) is a collection of discrete values that convey information, describing quantity, quality, fact, statistics, other basic units of meaning, or simply sequences of symbols that may be further interpret ...
that is valid ''now''.
For example, if a user inserts "John Smith" into the Staff table of a current database, this asserts that the fact is valid ''now'' and until it is subsequently deleted. By contrast, a
temporal database
A temporal database stores data relating to time instances. It offers temporal data types and stores information relating to past, present and future time.
Temporal databases could be uni-temporal, bi-temporal or tri-temporal.
More specifically th ...
qualifies each row with a valid
time ''stamp'', valid time ''period'' or valid time ''interval''. For example, we can assert the fact that "John Smith" was a member of staff during the period 1 June 2001 and ''now''. Current databases are the most common type of database in use today. The concept of ''now'' is discussed in Clifford
et alia (1997).
References
External links
*{{cite journal , last1=Clifford , first1=J. , last2=Dyreson , first2=C. , last3=Isakowitz , first3=T. , last4=Jensen , first4=C. S. , last5=Snodgrass , first5=R. T. , year=1997 , title=On the semantics of 'now' in databases , journal=ACM Transactions on Database Systems , doi=10.1145/249978.249980 , citeseerx=10.1.1.112.7301 , s2cid=1879036 , volume=22 , issue=2
Types of databases