Key Fields in a Database. Keys are crucial to a table structure for many reasons, some of which are identified below: 1  They ensure that each record in a table is precisely identified.  They help establish and enforce various types of integrity.
avifauna definition: The definition of avifauna are the birds that live in a certain place or at a certain time. (noun) An example of avifauna is penguins living primarily in Antarctica. An example of avifauna is the moa of New Zealand becoming extin...
vena cava (pl. venae cavae) one of the two major veins of the BLOOD CIRCULATORY SYSTEM that carry blood from other veins to the right atrium of the HEART. The inferior vena cava receives blood from parts of the body below the diaphragm; the superior vena cava drains blood from all parts of the body above the diaphragm. Vena cava