What is the main different between Null and NOT Null.
Difference between Primary and Unique Key.
How to Check the database from which application is it
possibe.
Answer Posted / g priya
If a field is null the database engine makes the field to be 0
if not null is specified ,field must be given a value
Primary key is unique,not null,index where as Unique key has
1 null value
| Is This Answer Correct ? | 2 Yes | 5 No |
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