Encyclopedia > Article

Key-value Stores

Key-value stores are probably the simplest form of database management systems. They can only store pairs of keys and values, as well as retrieve values when a key is known.

These simple systems are normally not adequate for complex applications. On the other hand, it is exactly this simplicity, that makes such systems attractive in certain circumstances. For example resource-efficient key-value stores are often applied in embedded systems or as high performance in-process databases.

Advanced Forms

An extended form of key-value stores is able to sort the keys, and thus enables range queries as well as an ordered processing of keys.

Many systems provide further extensions so that we see a fairly seamless transition to document stores and wide column stores.

Most popular examples

Find more systems in our key-value store ranking.