Interested to Buy Any Domain ? << Click Here >> for more details...
what is primary key,unique key, foreign key? can u teach me
in simple language?
- 44 Answers
- 189072 Views
- Banking, CMC, CTS, HCL, Infosys, Keggfarms, SkyEss, Sunrise, TCS, Web Synergies, Wipro, I also Faced
- E-Mail Answers
Answer Posted / charu gautam
primary key:- the primary key of a relational table uniquely
identifies each record in the table. it can either be a
normal attribute that is guaranteed to be unique . such as
social security number in a table with no more than record
per person or it can be generated by the D B M S .such as a
globally unique identifier ,or G U I D, in microsoft SQL
server primary key may consist of a single attribute or
multiple attribute in combination.
foreign key:- A foreign key is a field (or fields) that
points to the primary key of another table.The purpose of
the foreign key is to ensure referential integrity of the
data.In other words ,only values that are supposed to appear
in the database are permitted.
| Is This Answer Correct ? | 15 Yes | 5 No |
Post New Answer View All Answers
how to reject duplicates in source sequential file and if by filter option then where is that filter option in the sequential file.
What does currency type mean in database?
wHat Is THE difference between MOVEL and MOVEL(P)……….. CAN ANYONE EXPLAIN ME..
what is transaction state, buffer management, shadow paging
What is a reference table in database?
List the properties of a transaction.
Explain the field term used in database.
i applied prompt on country when i run report it shows list of all countries but want it to show only four countries name
What is the function of cluster index?
how node connect with cpu?
Is database a hardware or software?
hai if any one having any project sample table structure please froward to my mail id tauseefwst@yahoo.com
What are the most common databases?
Write a query to get maximum and second maximum in oracle?
What is a trace file?
