Railway RRB Junior Engineer JE Online Form 2018 Praveen Tiwari 01:12 Railway RRB Junior Engineer JE Online Form 2018 https://sarkariresults.info/2019/rrb-junior-engineer.php
What is alternate, artificial, compound and natural key? Alternate Key: Excluding primary keys all candidate keys are known as Alternate Keys. Artificial Key: If no obvious key either stands alone or compound is available, then the last resort is to, simply create a key, by assigning a number to each record or occurrence. This is known as artificial key. Compound Key: When there is no single data element that uniquely defines the occurrence within a construct, then integrating multiple elements to create a unique identifier for the construct is known as Compound Key. Natural Key: Natural key is one of the data element that is stored within a construct, and which is utilized as the primary key. 05:31
0 Comments
Post a Comment