Skip to main content

Some tricky SQL queries (Interview Questions)


1.Select nth highest salary and name from emp table
?
1
2
3
SELECT DISTINCT (a.empsalary),a.Employee_Name FROM empData A WHERE  N =(SELECT COUNT (DISTINCT (b.empsalary)) FROM empData B WHERE a.empsalary<=b.empsalary);
--where N is your number (2nd or 5th)
e.g SELECT DISTINCT (a.empsalary),a.Employee_Name FROM empData A WHERE  5 =(SELECT COUNT (DISTINCT (b.empsalary)) FROM empData B WHERE a.empsalary<=b.empsalary);

2.Select query without using "Like" operator . For eg select employee name start with 'j' and city is 'Noida' in company_name
?
1
select * from empdata where CHARINDEX('j',Employee_name)=1 and CHARINDEX('Noida',company_name)>0




3.Select query for grouping 2 coulmns in one column using Case statement
?
1
select result=case when p1 is not null then p1 when p2 is not null then p2 end from tbltest



4.Create identity like coulmn in query
?
1
select row_number () over( order by p1) as sno, result=case when p1 is not null then p1 when p2 is not null then p2 end from tbltest

Comments

Post a Comment

Popular posts from this blog

Tip/Trick: Fix Common SEO Problems Using the URL Rewrite Extension

Search engine optimization (SEO) is important for any publically facing web-site.  A large % of traffic to sites now comes directly from search engines, and improving your site’s search relevancy will lead to more users visiting your site from search engine queries.  This can directly or indirectly increase the money you make through your site. This blog post covers how you can use the free Microsoft  URL Rewrite Extension  to fix a bunch of common SEO problems that your site might have.  It takes less than 15 minutes (and no code changes) to apply 4 simple  URL Rewrite  rules to your site, and in doing so cause search engines to drive more visitors and traffic to your site.  The techniques below work equally well with both ASP.NET Web Forms and ASP.NET MVC based sites.  They also works with all versions of ASP.NET (and even work with non-ASP.NET content). [In addition to blogging, I am also now using Twitter for quick updates and to sh...
Post a Comment
Read more

ASP.NET MVC - Set custom IIdentity or IPrincipal

Here's how I do it. I decided to use IPrincipal instead of IIdentity because it means I don't have to implement both IIdentity and IPrincipal. Create the interface interface ICustomPrincipal : IPrincipal { int UserId { get ; set ; } string FirstName { get ; set ; } string LastName { get ; set ; } } CustomPrincipal public class CustomPrincipal : ICustomPrincipal { public IIdentity Identity { get ; private set ; } public bool IsInRole ( string role ) { return false ; } public CustomPrincipal ( string email ) { this . Identity = new GenericIdentity ( email ); } public int UserId { get ; set ; } public string FirstName { get ; set ; } public string LastName { get ; set ; } } CustomPrincipalSerializeModel - for serializing custom information into userdata field in FormsAuthenticationTicket object. public class CustomPrincipalSerializeMode...
8 comments
Read more

How to create a countdown timer in jquery

Create a countdown timer in jQuery First we need to include the jQuery library file to the HTML page to perform this task. To do that we need to understand that what exactly a jQuery library fie is ? JQuery library file is the library of JavaScript, which means this file contains the predefined functions of jQuery. We just need to call these functions to perform the task. jQuery functions reduces the lines of code and makes our task easy. As this jQuery library file contains the javascript functions so we need to call the function within <script> </script> tag. Now after including the file, we need to define a variable which will store that for how long you want the timer on the page(c=60) and now the time you set needs to be changed in hours , minutes and seconds using the code “ var hours = parseInt( time / 3600 ) % ;var minutes = parseInt( time / 60 ) % 60; var seconds = time % 60;” Now we need to put the condition if timer got finished (if (t...
1 comment
Read more