FUNDAMENTALS OF COMPUTER

Detailed explanation-1: -Each row in the relational table is known as an entity instance or entity occurrence in the ER model. M:N relationships are not appropriate in a relational model. The external model is the representation of the database as “seen” by the DBMS.

Detailed explanation-2: -A relation, also known as a table or file, is a subset of the Cartesian product of a list of domains characterized by a name. And within a table, each row represents a group of related data values. A row, or record, is also known as a tuple.

Detailed explanation-3: -In the context of a relational database, a row-also called a tuple-represents a single, implicitly structured data item in a table. In simple terms, a database table can be thought of as consisting of rows and columns.

Detailed explanation-4: -Each table row (tuple) represents a single entity occurrence within the entity set. Each table column represents an attribute, and each column has a distinct name and datatype. Each intersection of a row and column represents a single data value. All values in a column must conform to the same data format (datatype).

Detailed explanation-5: -An additional data object is the entity occurrence. Each row in a table represents a specific, single occurrence of the entity. For example, if customer is an entity, a customer table represents the idea of customer; in it, each row represents one specific customer, such as Sue Smith.