Question : Are these interview questions too hard for a data-centric .net developer?

I'm trying to fill a .net developer contract.  I'm asking a series of questions to gauge the overall experience level.  Even after rating themselves as an 8/10 or higher on all subjects people seem to be struggling with the following questions:

Put the following in order Button_Click, Page_PreRender, Page_Load

What is a generic collection?

What happens to a property or method if you make it 'static'

What is a singleton?

What is the difference between 'Show' and 'Show Dialog' (winforms)

What is the difference between the 'Activate' and 'Load' events (winforms)

When would you use the property called 'InvokeRequired' (i ask only if they say they have multithreading experience).
Describe the following:
ASPX,
ASCX,
ASMX
ASHX

How would you debug a for loop that didn't fail until it's 1000th iteration (most say modify the code).

How does an index speed up a query (DB)?

How does an index slow down other operations (DB)?

I also ask what is a left join which most seem to get, but then can't actually apply a left join.



I'm not looking for somebody to answer everything, but I would expect a developer of 5 years or more to be able to answer 70% of these questions and that is not the case.  What can I ask that isn't too hard yet will weed out those that are obviously embellishing their resume.

Answer : Are these interview questions too hard for a data-centric .net developer?

I've got about 3 years of working experience in .NET and I can answer all of those. Is that an indication?

To me, those questions don't seem very data-centric; rather they seem basic .NET knowledge-ish. But that's my opinion  :)

Data-centric questions to me would be more like:

    Which method of the SqCommand object would you call to return a single result from a database (single row, single column)?

   What problem(s) do you see with the following logic:

        cmd.CommandText = "SELECT * FROM permissions WHERE uid = '" + txtBox1.Text + "'";

    Under what namespace will you find the classes necessary to interact with a SQL Server DB?

 :)