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...
Define vena cava. vena cava synonyms, vena cava pronunciation, vena cava translation, English dictionary definition of vena cava. n. pl. venae caÂ·vae Either of two large veins that drain blood from the upper body and from the lower body and empty into the right atrium of the heart....