Golgappa.net | Golgappa.org | BagIndia.net | BodyIndia.Com | CabIndia.net | CarsBikes.net | CarsBikes.org | CashIndia.net | ConsumerIndia.net | CookingIndia.net | DataIndia.net | DealIndia.net | EmailIndia.net | FirstTablet.com | FirstTourist.com | ForsaleIndia.net | IndiaBody.Com | IndiaCab.net | IndiaCash.net | IndiaModel.net | KidForum.net | OfficeIndia.net | PaysIndia.com | RestaurantIndia.net | RestaurantsIndia.net | SaleForum.net | SellForum.net | SoldIndia.com | StarIndia.net | TomatoCab.com | TomatoCabs.com | TownIndia.com
Interested to Buy Any Domain ? << Click Here >> for more details...

what is the difference between unique and primary key

Answer Posted / divyarao

primary key accepts only values which has no duplication ,and does not accept null values . for a a table there should be only one primary key constraint.
whereas in unique key ,it accepts null values .here also there should not be any duplication ,a table may have more than one unique key constarint

Is This Answer Correct ?    0 Yes 0 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

What is implicit cursor in dbms?

966


What is stored in a database?

898


Where is database data stored?

840


What are the disadvantages of a query?

967


What is a sequence in a database?

915


Is there some bulk load or other way to import a lot of data fast?

807


What do you understand by database triggers?

884


What is vacuum in database?

832


What is order by clause?

870


Explain data independence?

967


Operators used in select statements are?

870


Define view, sequence and index in DBMS.

875


Why rdbms is not suitable for big data?

940


What is the structure of a database?

874


State some commands of ddl in dbms?

962