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
What is the normal procedure followed by a java client to access the db?
Define scalar functions.
What are the examples of database?
Define atomicity and aggregation.
How to migrate paradox, dbase or foxpro database to firebird?
Explain a checkpoint and when does it occur?
How do you create a report in a database?
Define union all operator and union.
What do you understand by the terms entity, entity type, and entity set in dbms?
What is a Federated Query ?
What is like operator for and what are wild cards?
Which database is best for storing large data?
Why do we need database management?
What is the rdbms concept in sql?
What is cold backup (in case of oracle)?