<P> An entity -- relationship model ( ER model for short ) describes interrelated things of interest in a specific domain of knowledge . A basic ER model is composed of entity types ( which classify the things of interest ) and specifies relationships that can exist between instances of those entity types . </P>
<P> An entity -- relationship model ( ER model for short ) describes interrelated things of interest in a specific domain of knowledge . A basic ER model is composed of entity types ( which classify the things of interest ) and specifies relationships that can exist between instances of those entity types . </P>
a diagramming tool used to express the relationships between entities in a database is called a
a diagramming tool used to express the relationships between entities in a database is called a
entity -- relationship model
entity -- relationship model