One-to-many (data model)

A mother may have many children, but a child has only one mother

In systems analysis, a one-to-many relationship is a type of cardinality that refers to the relationship between two entities (see also entity–relationship model) A and B in which element of A may be linked to many elements of B, but a member of B is linked to only one element of A. For instance, think of A as mothers, and B as children. A mother can have several children, but a child can have only one mother.

See also

• One-to-one (data model)
• Many-to-many (data model)

External links

• Design pattern: many-to-many (order entry), Tomjewett.com