Database Constraints
A relational database is a collection of data items organized as a set of formally described tables from which data can be accessed easily. A relational database is created using the relational model. The software used in a relational database is called a relational database management system (RDBMS). A relational database is the predominant choice in storing data, over other models like the hierarchical database model or the network model. It consists of n number tables and each table has its own primary key.
The relational database was first defined in June 1970 by Edgar Codd, of IBM's San Jose Research Laboratory.
Read more about Database Constraints: Terminology, Relations or Tables, Base and Derived Relations, Constraints, Relational Operations, Normalization, Relational Database Management Systems
Famous quotes containing the word constraints:
“The analogy between the mind and a computer fails for many reasons. The brain is constructed by principles that assure diversity and degeneracy. Unlike a computer, it has no replicative memory. It is historical and value driven. It forms categories by internal criteria and by constraints acting at many scales, not by means of a syntactically constructed program. The world with which the brain interacts is not unequivocally made up of classical categories.”
—Gerald M. Edelman (b. 1928)