A relational DBMS is a table-oriented store based on the relational model (originally described by Edgar F. Codd). Such databases comprise a number of records (entities), each corresponding to a row in a table. The records (entities) contain attribute values.
Relation schemas within a database table are defined by the table name, a fixed number of attributes, and fixed data types. The schemas are the product of normalization in the course of data modeling.
Operations within such databases are performed using a database language—most commonly SQL.
Examples of relational DBMS are Oracle, MySQL, Microsoft SQL Server, PostgreSQL, and DB2.
