what is primary key,unique key, foreign key? can u teach me
in simple language?
Answers were Sorted based on User's Feedback
Answer / pounammal sambath
primary key:
* primary key is the key which is used to for unique identification of the row in the table.
*it does not allows the duplicate and null values.
Is This Answer Correct ? | 0 Yes | 1 No |
Answer / patel gopikumar
PRIMARY KEY : it is a key that not allow null value in database tables field....
UNIQUE KEY : it is a key that store or manage data uniquely...
FOREIGN KEY : it is key that use is...connect two fields in the different tables........with foreign key......
thnks........
s-150907-007 PATEL GOPIKUMAR
Is This Answer Correct ? | 5 Yes | 12 No |
Answer / sri lekha
a key to open primary school is primary key
a key for foreign schools is foreign key
answering this way is unique
Is This Answer Correct ? | 16 Yes | 44 No |
Answer / manmohan singh
The key to Prime Ministers office in delhi is known as
primary key. The key to Foreign Secy's cabin is foreign key.
Is This Answer Correct ? | 114 Yes | 263 No |
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