What is data cube?

Codd was one of the originators of the relational database and so his opinions were respected. However Codd was paid to write the white paper to support Arbor's existing Essbase product, rather than the concept being mathematically-based. Neverthless Codd's reputation legitimised a useful new arrangement of data in arrays to allow fast analysis. These arrays are called cubes. The arrangement of data into cubes avoids a limitation of relational databases which are not well suited for near instantaneous analysis of large amounts of data. Relational databases are better suited for creating records from a series of transactions (known as OLTP or on-line transaction processing). Although many report-writing tools exist for relational databases, these are slow when the whole database must be summarised. Codd's paper was viewed as propaganda that users could show to skeptical IT departments who had often thought that everything their users wanted could be done from a relational database.