Cơ sở dữ liệu - Relational Model

Relational data model: represents a database in the form of relations - 2-dimensional table with rows and columns of data. A database may contain one or more such tables. A relation schema is used to describe a relation
Relation schema: R(A1, A2,…, An) is made up of a relation name R and a list of attributes A1, A2, . . ., An. Each attribute Ai is the name of a role played by some domain D in the relation schema R. R is called the name of this relation