Define candidate key, alternate key, composite key?
Answer Posted / sanjay p sonar
Candidate key:-A candidate key is unique. We may say that
candidate key is another name of primary key. We can have
more than one candidate key. From which we have to choose
one as a primary key.
Alternate key:-The Candidate key other than primary key is
Alternate key. We can have more than one Alternate keys.
Composite key:- When we combine more than 1 column by key
then that key is called Composite key
Clustered Key:- When we combine more than 1 column to form
Primary key then it will become Cluster key.
| Is This Answer Correct ? | 0 Yes | 0 No |
Post New Answer View All Answers
Explain about relational database management systems?
Why does this query return 0?
Explain about the storage and physical database design?
Explain about normal forms?
What is dbms explain in brief?
Explain about query and reporting.
Any sample or model question of punjab national bank for deputy manger IT or any sample of PNB.any1 plz do send on
How to combine two function together?
What is the physical representation for a many-to-many relationship?
To convert IDMS to DB2, how to deal with IDMS occurs and redefined clause?
In which table collections errors are stored.
Write the fastest query to find out how many rows exist in a table?
Explain about network model?
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?
A) Which two are benefits of Teradata's support for ANSI Standard SQL? (Choose two.) 1.data is distributed automatically 2.queries get optimized to better plans 3.submit queries from other database systems 4.can interface with BI tools B) Which statement is true when comparing the advantages of third normal form to star schema? 1.Star schema tends to have fewer entities. 2.Star schema requires additional data storage. 3.Third normal form tends to have fewer entities. 4.Third normal form requires additional data storage. C)Which two sets of functions does the Parsing Engine (PE) perform? (Select two.) 1.sorting, formatting, and aggregating of the final answer set 2.flow control of the data to and from the participating tables 3.SQL statement interpretation, syntax validation, and semantic evaluation 4.dispatching the step execution sequence to the AMP via the BYNET D) Which two can be achieved with Teradata Active System Management (TASM)? (Choose two.) 1.disable hardware 2.react to hardware failure 3.influence response times 4.collect metadata E) Which three mechanisms can be used to ensure security within the Teradata Database? (Choose three.) 1.views 2.spool limits 3.roles 4.access rights 5.profiles