Interested to Buy Any Domain ? << Click Here >> for more details...
how to check the 3rd max salary from an employee table? One
of the queries used is as follows:
select sal from emp a where 3=(select
count(distinct(sal)) from emp b
where a.sal<=b.sal).
Here in the sub query "select
count(distinct(sal)) from emp b
where a.sal<=b.sal" or
"select count(distinct(sal)) from emp b
where a.sal=b.sal" should reveal the same number of rows is
in't it? Can any one here please explain me how is this
query working perfectly.
However, there is another query to get the 3rd highest of
salaries of employees that logic I can understand. Pls find
the query below.
"select min(salary) from emp where salary in(select
distinct
top 3 salary from
emp order by salary desc)"
Please explain me how
"select sal from emp a where 3=(select
count(distinct(sal)) from emp b
where a.sal<=b.sal)" works
source:http://www.allinterview.com/showanswers/33264.html.
Thanks in advance
Regards,
Karthik.
- 4 Answers
- 8629 Views
- I also Faced
- E-Mail Answers
Answer Posted / gaurav
If you use "select count(distinct(sal)) from emp b
where a.sal=b.sal" It will always give output as 1. because for every salary in emp a, there will be one distinct sal in emp b.
So when we use a.sal <= b.sal, we are counting the number of people who have salary greater than or equal to your salary. So comparing it with 3 will give us 3rd maximum salary.
| Is This Answer Correct ? | 0 Yes | 0 No |
Post New Answer View All Answers
what is bcp? When is it used?
Can we insert data in view?
What is the file extension for sql database?
What is dialect in sql?
Explain the difference between cursor declared in procedures and cursors declared in the package specification?
How can I change database name in sql?
What is difference between inner join and cross join?
What is the purpose of normalization?
What are tables in sql?
what is a primary key? : Sql dba
What is embedded sql in db2?
Which join is like inner join?
Why do you partition data?
What is the difference between a database and a relational database?
How to change sql*plus system settings?
