A relational database is a database based on the relational model. Strictly speaking the term refers to a specific collection of data but it is often used synonymously with the software that is used to manage that collection of data. That software is more correctly called a relational database management system, or RDBMS.

See also

• Database management system (DBMS)
• Entity relationship diagram (ERD)
• Flat file database

Experimental Variations

Dynamic Relational http://c2.com/cgi/wiki?MultiParadigmDatabase extrapolates the concept of "dynamically-typed programming languages" to relational databases. It includes concepts such as on-the-fly column creation, on-the-fly table creation, and perhaps could double as an OODBMS if entity-designation is optional or not used. Every record has a unique "record ID" or "object ID" that could serve as a primary key if an entity-based one is not available. Typing for columns (designation as numeric, date, etc.) would be optional, but would be stored with the schema instead of per-cell if included. Columns could also be designed as "required" if needed. With enough specification (types, limits, etc.), it could act just like a traditional RDBMS if needed.

External links

• A Relational Model of Data for Large Shared Data Banks http://www.acm.org/classics/nov95/toc.html : By E. F. Codd
• Relational Database Principles by Colin Ritche. ISBN 0826457134 This is Very Helpful for courses where databases are a course module.