Database Flashcards
relational database
allows the user to specify information about multiple tables and the relationship between those tables
primary key
a field that uniquely identifies a record in a table
secondary key
a key field which can be used to access a table in a different way, and allows a database to be searched quickly
entity relationship
a relationship between 2 entities signifies that the two entities are associated with each other somehow
entity relationship modelling
the process of producing a data model for describing the data or information aspects of a business domain or its process requirements, in an abstract way that lends itself to ultimately being implemented in a data such as a relation database
foreign key
attribute that links 2 tables together, primary in one and foreign in another
composite key
when more than one field is added together to form a unique primary key for a table
referential integrity
the process of ensuring consistency, ensures that information is not removed if it is required elsewhere in a linked database. If 2 database tables are linked, one of these tables cannot be deleted as the other table requires its contents
one to one relationship
each entity can only be linked to one other entity eg husband and wife
one to many relationship
one table can be associated with many other tables, such as a mother having multiple children