Types of indexes. What is the default key created when a
primary key is created in a table ?
Answers were Sorted based on User's Feedback
Answer / mahesh
Major indexes are B-tree and Bitmap indexes
When ever we create a primary key, B-tree index will be
created
| Is This Answer Correct ? | 15 Yes | 3 No |
Answer / sdp
A unique index is created when a primary key is created in
a table.
| Is This Answer Correct ? | 10 Yes | 3 No |
Answer / suren
while creating primary by default a unique index is created
| Is This Answer Correct ? | 4 Yes | 0 No |
Answer / manish_patil
There are main two types of indexes,
B-tree index
Bitmap index.
While creating Primary key by default cluster index get
crated.
| Is This Answer Correct ? | 7 Yes | 5 No |
Does view contain data?
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.
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