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 can be uni-temporal, bi-temporal or tri-temporal.

More specifically the temporal aspects usually include valid time, transaction time and/or decision time.

A uni-temporal database has one axis of time, either the validity range or the system time range.

A bi-temporal database has two axes of time:

A tri-temporal database has three axes of time:

This approach introduces additional complexities.

Temporal databases are in contrast to current databases (not to be confused with currently available databases), which store only facts which are believed to be true at the current time.

Temporal databases support managing and accessing temporal data by providing one or more of the following features: