why can't we assign not null constraint as table level
constraint
Answers were Sorted based on User's Feedback
Answer / lokanath
Because its a Column Level constraint.
Not Null is a Constraint which will ensure the Column
should not be null.
| Is This Answer Correct ? | 10 Yes | 12 No |
Answer / senthil
not null constraint applied on table level constraint but table must be empty otherwise not possible .
| Is This Answer Correct ? | 0 Yes | 3 No |
Answer / newton_dba
A NOT NULL CONSTRAINT IS USAUALLY APPLIED ON COLUMN LEVEL
BUT IT CAN BE APPLIED ON THE TABLE LEVEL BY USING ALTER
TABLE STATMENT
ALTER TABLE EMP
MODIFY (ENAME CONSTRAINT EMP_ENAME_NN NOT NULL);
| Is This Answer Correct ? | 7 Yes | 13 No |
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