Relational Model Basics Quiz

A1, A2, …, An are attributes. R = (A1, A2, …, An ) is a relation schema.

A relation instance r defined over schema R is denoted by r (R).

Attributes are the columns in a relation that define the characteristics or properties of the data.

<p>The set of allowed values for each attribute is called the domain of the attribute.</p> Signup and view all the answers

<p>The special value 'null' is a member of every domain.</p> Signup and view all the answers

<p>The structure of relational databases includes database schema, keys, and schema diagrams.</p> Signup and view all the answers

<p>A relation schema is a set of attributes that defines the structure of a relation.</p> Signup and view all the answers

<p>Relation instances are denoted by r(R), where r is the current values of the relation over the schema R.</p> Signup and view all the answers

<p>Attributes in the context of relational databases are the columns or fields that represent the properties of an entity.</p> Signup and view all the answers

<p>The domain of an attribute in relational databases is the set of allowed values for that attribute.</p> Signup and view all the answers

<p>Atomic Values</p> Signup and view all the answers

<p>A placeholder for missing or unknown attribute values</p> Signup and view all the answers

<p>The set of all possible attribute values</p> Signup and view all the answers

<p>Relation Instance</p> Signup and view all the answers