Integrity Constraints - Types

Types

Codd initially defined two sets of constraints but, in his second version of the relational model, he came up with four integrity constraints:

Read more about this topic:  Integrity Constraints

Famous quotes containing the word types:

    The bourgeoisie loves so-called “positive” types and novels with happy endings since they lull one into thinking that it is fine to simultaneously acquire capital and maintain one’s innocence, to be a beast and still be happy.
    Anton Pavlovich Chekhov (1860–1904)

    He types his laboured column—weary drudge!
    Senile fudge and solemn:
    Spare, editor, to condemn
    These dry leaves of his autumn.
    Robertson Davies (b. 1913)

    Our major universities are now stuck with an army of pedestrian, toadying careerists, Fifties types who wave around Sixties banners to conceal their record of ruthless, beaverlike tunneling to the top.
    Camille Paglia (b. 1947)