Answer Posted / lekhraj deshmukh
An index covers the query if all the columns specified in
the query are part of the index. These are the columns that
are all columns referenced in the query, not just columns in
a WHERE clause.
eq:-SELECT DISTINCT lower(orig_airport) FROM Flights
here orig_airport is a index column.
| Is This Answer Correct ? | 3 Yes | 1 No |
Post New Answer View All Answers
What is difference between count (*) and count 1?
How to get the definition of a trigger back?
wat wil hapn if we give the both read and deny read permission to user?
What is BCP? When does it used in sql server 2012?
Explain the phases a transaction has to undergo?
How do I view a procedure in sql server?
Can we insert data into a view?
What is the guest user account in sql server? What login is it mapped to it? : sql server security
Can I delete event logs?
What are system databases into sql server (2005/2008) : sql server database administration
What are the dis_advantages of stored procedures, triggers, indexes?
What new data source types were added in ssrs 2014?
What is difference between table aliases and column aliases? Do they affect performance?
What are the methods used to protect against sql injection attack?
What is a fill factor?