what is the difference between primary key & foreign key?
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Answer / anil bharodiya
Primary key is field of the table that can be used to
uniquely identify records of the table
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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.........
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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
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Answer / raja
foriegn key always refers to
primary key but Primary key is unique key
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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.
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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.
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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 |
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