what is the difference between primary key & foreign key?
Answers were Sorted based on User's Feedback
Answer / anil bharodiya
Primary key is field of the table that can be used to
uniquely identify records of the table
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / sripathi venkata ramesh
I am Sripathi Venkata Ramesh from Gudivada and the answer
is mentioned below
Primary key: A Primary key is a column or group of columns
used to uniquely identify each row in a table like
It defines the column as a Mandatory column.
The data held across the column must be unique.
By default it creates clustered index.
It does not allow null values and duplicate values
Foreign key: A Foreign key is a column or group of columns
whose values are derived from the primary key of some other
table
| Is This Answer Correct ? | 2 Yes | 2 No |
Answer / bharathi sundar
A PRIMARY KEY DOES NOT ACCEDES DUPLICATIONS .
A FOREIGN KEY IS USED FOR LINKING TWO DATABASE TABLES
ABSTRUSELY .
A FOREIGN KEY USES THE PRIMARY KEY IN ANOTHER TABLE,
TO RETRIEVE OR TO IDENTIFY THE CELL VALUES IN ANOTHER
TABLE.........
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / sravan kumar
A attribute which it is uniquely identifies in a row in a
table is called Primary key..
A column in a table whose values matches the primary key in
some other table is called Foreign key
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / raja
foriegn key always refers to
primary key but Primary key is unique key
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / suneel manne
Primary key is a key it will allow only Unique values and
avoid duplicate values and foreign key is a reference key
from the other table, So here primary key acts as a parent
key and foreign key acts as a child key.
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / ibrahim
A primary key is an combination of attributes that uniquely
identifies each row in a relation. A primary key is
designated by underlining the attribute name. The primary
key of an entity set allows us to distinguish among the
various entities of the set.
A foreign key is an attribute in a relation of database
that serves as the primary key of another relation in the
same database.
| Is This Answer Correct ? | 0 Yes | 1 No |
Answer / kush kaushik
Primary key is primary means from india and foreign key is forgeiner means from forign .. ..By kush kaushik(kush.kaushik87@gmail.com)
| Is This Answer Correct ? | 0 Yes | 1 No |
Without giving condition how to retrieve the unmatched records from table.
How to connect ms access to oracle servers?
which institute and which faculty is providing best training for oracle sql, plsql in hyderabad
How to create a new table in oracle?
What is the effect of setting the value of OPTIMIZER_MODE to 'RULE' ?
How to connect to the server with user account: sys?
What is the difference between normal and corelated subqueries?
How to convert times to characters in oracle?
What is OCI. What are its uses?
what's query optimization and without use of IN AND Exist can we get another way data from query
What is the difference between hot backup and cold backup in oracle? Tell about their benefits also.
What is the difference between view and materialized view in Oracle?