Interested to Buy Any Domain ? << Click Here >> for more details...
what is the difference between primary key & foreign key?
- 57 Answers
- 135100 Views
- CTS, Infosys, La Multi, Sparsh, Wipro, I also Faced
- E-Mail Answers
Answer Posted / ansul singh
Primary key is unique key but Foreign key always refers to
primary key.
Primary key is the parent & Foreign key is the child.
Primary key is unique, Primary key is not null and
Foreign key is null, Foreign key reference as primary key
is another table.
Primary key will not allow "Null values" & "Duplication
values",
Foreign key will allow "Null values & "Duplicate values" &
it refers to a primary key is another table.
| Is This Answer Correct ? | 1 Yes | 0 No |
Post New Answer View All Answers
How to join two tables in a single query using oracle?
Where are the settings stored for each instance in oracle?
How to use "while" statements in oracle?
How to define a data field as not null?
In not less than 100 words what's the main difference between Rolap and Molap in ORACLE ?
How to rename a column in an existing table?
How to define a record variable to store a table row?
Can we write insert statement in function in oracle?
How do I reset a sequence in oracle?
Can we use oracle pl/sql block in core java? if so how? pls get back to me .....
What is the string concatenation operator in oracle?
Can you drop an index associated with a unique or primary key constraint?
What is connection pooling in oracle?
What are the differences between blob and clob in oracle?
How to invoke the data pump export utility?
