Explain the key constraints and constraints on Null Values
with examples?
Answer Posted / amit
hi ,
key constraits i.e. referential integerity means
all values in foreign key must be in primary key , but it
may happnes that NULL values may be in foreign key , but
not in primary key .
this is done to cater some of the exception conditions.
| Is This Answer Correct ? | 4 Yes | 1 No |
Post New Answer View All Answers
Is dynamodb a document database?
What is openedge workgroup rdbms?
Why is group-clause used?
What do you understand by cursor?
Explain 3nf?
What is the instance of a relation?
how to retrive a data From database into the grid view..?
What is index hunting and how does it help in improving query performance?
What do you mean by cardinality and its types?
What are the restrictions applicable while creating views?
what is scan listener.
What is rdbms with diagram?
What does you mean by s4 super key?
What is the difference between delete and truncate command in dbms?
How to improve query performance using index hunting?