What Is The Difference Between Primary Key & Super Key
Answers were Sorted based on User's Feedback
Primary Key is a column which uniquely identifies all records in a table. For example EmployeeID column in an Employee table.
If you add another column to a PK, like (EmployeeID+FirstName) it still identifies identifies all rows uniquely, is known as Super Key.
For more interview Questions on SQL Server: http://sqlwithmanoj.wordpress.com/interview-questions/
Is This Answer Correct ? | 11 Yes | 0 No |
Answer / tanmay dutta
Primary Key : Unique No. Not null.No duplicate.exam:Student_Id.
Super Key : Like (student_id + Student Name)
Is This Answer Correct ? | 2 Yes | 0 No |
Answer / anil kumar dubey
A candidate key that uniquely identifies a row in a table is called primary key.
A superkey (composite key) is a combination of columns that uniquely identifies any row within a relational database management system (RDBMS) table.
Is This Answer Correct ? | 0 Yes | 0 No |
I create a separate index on each column of a table. What are the advantages and disadvantages of this approach? : Sql server database administration
Wht is SQL Injection Attack ?
If i have one transaction say mainTransaction, within this mainTransaction i have another two transaction say t1 and t2. Now while execution t1 completes successfully and commit statement fires, but while executing t2 some error occurs and rollback statement fires. What happen to t1, is it rollback or not?
What is Data model and how to prepare a data model.?
As per your opinion what are the five top responsibilities of a dba? : sql server database administration
What is lookup override?
How do I find my localdb version?
Explain the concepts and capabilities of sql server?
how many type of subquery?
system date format is "yy-mm-dd" "select getdate()" ----> 2009-01-24 20:03:28.513 if i write "select dateadd(dd,2,getdate()) ".it returns "2009-01-26 19:59:38.340"...my question is dat could it be possible to retrive da date in da format "26 jan 2009 ...."??
What are the types of sql server?
How to see existing views in ms sql server?