What's the difference between a primary key and a unique key?
Answer Posted / amit
-Both are Unique means they do not accept duplicate value.
-Primary key by default Clustered Index where as Unique Key
is a Non-Clustered Index.
-Primary Key does not accept null value where as Unique Key
accept only one Null Value.
-A table can have only one Primary Key where as A table can
have multiple Unique Key.
| Is This Answer Correct ? | 2 Yes | 0 No |
Post New Answer View All Answers
What are filegroups in sql server?
Comment,Datatypes are unlimited
Does sql server use java?
What is openrowset sql server?
What do you understand by SQL*Net?
What is Federation Root Database?
Can one drop a column from a table?
Explain what are the basic functions for master, msdb, model, tempdb databases?
what is a join and explain different types of joins? : Sql server database administration
What is the default value of an integer data type in sql server 2005?
Do you know the capabilities of cursors?
Can you explain how long are locks retained within the repeatable_read and serializable isolation levels, during a read operation with row-level locking?
What are the differences between INNER JOIN, LEFT JOIN and RIGHT JOIN in SQL Server?
What is key attribute?
What are the steps you should follow to start sql server in single-user mode?