Is primary key = unique key,not null?
If yes,please explain
IF No,please explain
Answer Posted / neeraj
No, Both are different, If we use the combination "unique+not null" the referential integrity is not maintained and that is not the case with primary key.
I think you got the difference.
| Is This Answer Correct ? | 3 Yes | 1 No |
Post New Answer View All Answers
Can sub procedure/function be called recursively?
What is oracle thin client?
How to use "if" statements on multiple conditions?
How to write date and time literals in oracle?
What are the different types of failures that occur in Oracle database?
What are the uses of Database Trigger ?
Which is better Oracle or MS SQL? Why?
How to update a table row with a record?
How would you begin to troubleshoot an ORA-3113 error?
Can multiple columns be used in group by in oracle?
Give the various rollback segment states.
In XIR2 if we lost the administration password .How can we regain the password?thanks in advance.
Can I create users through internet explorer in oracle 10g?
What is null value in oracle?
What do you know about normalization? Explain in detail?