Constraint example sentences

The Integrity constraints, specified on database schema, must hold in every database state of that schema.Each of these models, which consist of a set of relations (or tables) and the integrity constraints, constitutes the database design for accounting.This can be shown diagrammatically as shown in figureure 1 2 Therefore, minimal super-key (also called Key) is defined as that part of super-key from which any attribute cannot be removed without sacrificing the uniqueness constraint.The insert operation is capable of violating any of the four constraints discussed above.Retrieval operation on Relational Data Model does not cause violation any integrity constraints.A relational database schema is a set of relation schemas and a set of integrity constraints.Governments in many countries run huge deficits forcing them to eventually put in place self-imposed constraints of not increasing expenditure over pre-determined levels (Box 1 gives the main features of the FRBMA in India).Any such super-key, therefore, specifies uniqueness constraint.Whenever applied, these operations must enforce integrity constraints specified on relational database schema.This constraint is specified to maintain consistency among the tuples of such relations.Participation constraint specifies as to whether the existence of an entity type depends on its being related to another entity via a relationship type or not.But in any case, it is a constraint that does not allow any two-entity instances from having the same value for the key attribute at a point of time.Besides this, it has the capability to define useroriented views of database, specify security and authorisation, define integrity constraints and various other operations.The referential integrity constraint stands violated in above example, if there is a debit or credit code in voucher relation, the tuple for which does not exist in Accounts relation.These include unrealistic standards, defective process, inadequacy of resources, structural drawbacks, organisational constraints and environmental factors beyond the control of the organisation.