Relational Database Modeling

Entity

object / event which can be distinctly identified

Table

contains a group of related entities in rows and columns called an entity set

Tuple

a row or record in a relation

Attribute

a field or column in a relation

Primary key

attribute or combination of them that uniquely identify each tuple in relation

Candidate key

attribute that can potentially be a primary key

Foreign key

attribute or combination of them that relates 2 different tables

Referential integrity

prevents users or applications from entering inconsistent data

Secondary key

candidate keys not chosen as the primary key

Indexing

creating a secondary key on an attribute to provide fast access when searching on that attribute: indexing data must be updated when table data changes