adspace
If we declare constraints Unique and Not null on a single
column then it will act as a Primary key, so what is the use
of primary key??
Answer Posted / ashok
Internally , There is same as primary key and unique not null.
You can say unique + not null is higher step of primary key .
So there is no basic difference between this two.
| Is This Answer Correct ? | 7 Yes | 11 No |
Post New Answer View All Answers
what is dbms? : Sql dba
Is inner join faster than left join?
Can delete statement be rollbacked?
Can we use distinct and group by together?
Can we rollback truncate?
what is schema? : Sql dba
how to start mysql server? : Sql dba
What is your daily office routine?
What is the best sql course?
Do we need to rebuild index after truncate?
how to escape special characters in sql statements? : Sql dba
what are all the common sql function? : Sql dba
what is bcp? When does it used? : Sql dba
what is collation? : Sql dba
Is primary key always clustered index?