Define candidate key, alternate key, composite key?
- 30 Answers
- 137649 Views
- IAS, IBM, I also Faced
- E-Mail Answers
Answer Posted / ramesh
A composite Key can be either Primay or Unique Key
More then One Key columns are said to be composite keys
Candidate Key(Primary Key) is a Key which Maintains the Row
Uniue .Can be defined based on the Entity
Alternate Key or Unique Key is similar to PK ,except it
accepts null Values .So that the records can still be
entered submitting null values to this attribute.
| Is This Answer Correct ? | 151 Yes | 207 No |
Post New Answer View All Answers
Explain the cube operator?
What are the constraints on severity level in raiseerror?
In which database can extended stored procedures be added?
What is the maximum length of an extended property?
What are the three basic rules which are to be followed for the relational model of the database?
How to generate OIDS
When installing the datastage7.5x2 edtion iam getting aproblem i.e the cpu count is 2 but the cpu count in installation is one . how can i install in my p.c (system is dual core).
Explain about the relational database?
Can an extended stored procedure be called from inside a user-defined function?
There is a trigger defined for INSERT operations on a table, in an OLTP system. The trigger is written to instantiate a COM object and pass the newly insterted rows to it for some custom processing. What do you think of this implementation? Can this be implemented better?
How to replace not in with not exist?
How is data stored in dbms?
You have a table with three columns: amount1, amount2, and amount3 in a single row only one of these three columns will have a value and the other two will be null. Write a sql query to retrieve the values from these columns?
Which data type cannot be used as a parameter in a udf?
Explain the role of indexing in databases?
