What are constraints? Explain different types of
constraints?

Answer Posted / henry

Constraints are used to restrict or protect the data and
accessing from the table
There are 5 types of constraints available,
That,
1.Primary-which is not allowed duplication and Null values
2.Unique-Which is also Not allowed duplication But It is
allowed one single null values
3.Foreign - Which is allowed duplication and Null values.
But It refers Value from primary Key table to its own table
Value.
4.Check Constratints
5.Not null

Is This Answer Correct ?    5 Yes 8 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

How to create a ddl trigger using "create trigger" statements?

617


Describe in brief sql server monitoring ways.

591


What are diverse clauses that form a part of sql?

602


What is the difference between resultset and resultsetmetadata?

522


how many triggers you can have on a table? : Sql server database administration

499






if no size is defined while creating the database, what size will the database have? : Sql server administration

550


How global temporary tables are represented and its scope?

552


What are the properties of the transaction?

550


How to delete all rows with truncate table statement in ms sql server?

494


Create and insert into temp table in sql server?

587


What extended events?

555


How to create percentile function?

108


Where actually sql azure database is hosted?

149


How to create median function?

118


What happens when unicode strings concatenate with non-unicode strings?

552