What is the use of placing primary key and foreign key
constrains on columns.
Answers were Sorted based on User's Feedback
Answer / jagadeesh b
If you maintain this relation ship you can get more advantages
1)you can not delete primary table directly..
2)duplicate values are not allowed in primary key table.
3)Null values are not inserted into primary key table so
validation is very easy fro m front end.(for ex; .net 2005).
| Is This Answer Correct ? | 3 Yes | 0 No |
Answer / deepak
1) PRIMARY KEY IS USED AS UNIQUE KEY, FOR AVOID DUPLICATION.
2) FOR VALIDATING DATA FROM PRIMARY KEY TABLE FOREIGN KEY USE.
| Is This Answer Correct ? | 1 Yes | 0 No |
Answer / rajendraprasad cherukuri
To segregate the data in different tables belongs to a
particular entity so that data can be retrieved when
required more economically and in a faster way.
| Is This Answer Correct ? | 0 Yes | 0 No |
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