what is mean by prmary key and foreign key and how can we
diffrentiate that?
Please answer me.
Advance thanks.
Answers were Sorted based on User's Feedback
Answer / ravi singh
Primary Keys: Primary keys are the identifier and applied
on the table in the form of constraints. Primary key
provides uniqueness in the data.
Foreign Key: Foreign Keys are the relationship and applied
on the table in the form of constraints. Foreign key in a
table is a primary key of another table and use to make
relationship between two tables.
| Is This Answer Correct ? | 59 Yes | 3 No |
Answer / cm
example :
primary key table: emp ( ENO, ename, address)
here eno is primary key
foreign key: table hari( ENO, phone, salary)
here same eno from hari table is used to get the values
from emp.
| Is This Answer Correct ? | 32 Yes | 1 No |
Answer / sandeep.n
primary key means to provide the information that the
colomn belongs to the same table, where as the forigen key
means to get the data from other table.
| Is This Answer Correct ? | 14 Yes | 4 No |
Answer / ysailajasantosh
Primary key means a unique key which is constant.
A foreign key (FK) is a column or combination of columns
that is used to establish and enforce a link between the
data in two tables. You can create a foreign key by
defining a FOREIGN KEY constraint when you create or modify
a table.
| Is This Answer Correct ? | 7 Yes | 1 No |
Answer / harish
LET ME TELL IN SINGLE SENTENCE!!! :)
"ALL FOREIGN KEYS ARE PRIMARY KEYS BUT NOT VICE-VERSA"
| Is This Answer Correct ? | 7 Yes | 2 No |
Answer / ritesh singhq
primary key is a complete date for all the member and
subject like and employee and all the data like
sale : note book pen pencil eraser
foreign key is a complete data of particular 1 thing like
note book : company name , numn of note book , creation
date etc
| Is This Answer Correct ? | 4 Yes | 0 No |
Answer / nimmi
PRIMARY KEY : IS THE UNIQUE KEY OF A SINGLE TABLE THAT IS
THE UNIQUE IDENTIFICATION OF THE SAME TABLE.
FOREIGN KEY: MEANS A UNIQUE KEY IDENTIFICATION COMMON TO TWO
TABLES .
| Is This Answer Correct ? | 4 Yes | 1 No |
Answer / b.jaganathan
PRIMARY KEY: the key which is used in the database table
for an identification is said to be a "PRIMARY KEY"....
FOREIGN KEY: the key which is used in the another database
table is said to be a foreign key, for the specified data
table........
| Is This Answer Correct ? | 2 Yes | 1 No |
Answer / dheeban02
primary key is used as unique key and foreign key is referred
with foreign key
| Is This Answer Correct ? | 3 Yes | 3 No |
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