Nothing more than a few sentences. There is no word limit. I would not put more than a paragraph into it.

Nothing more than a few sentences. There is no word limit. I would not put more than a paragraph into it."Databases can enforce business rules on permissible values by implementing declarative constraints in the database. These include NOT NULL, CHECK, UNIQUE, REFERENTIAL INTEGRITY, and PRIMARY KEY constraints. Why are these so important yet so often ignored by developers? What are the long term problems when these constraints are not implemented? "