Can we use more than one null value for unique key?
Answer Posted / christina
Yes, We can use more then one null value in unique key ,
because "null" means undefined or unknown so we can add any
number of null values in unique key...
This is the major difference between primary nd unique key,
Primary key doesn't allow null values to be entered into
the columns marked as priamry key and Unique allow us to
enter null values...............
Is This Answer Correct ? | 5 Yes | 2 No |
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