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Good C# Interview Questions for a Senior Dev Position
What questions would you ask, specifically? If you were looking for a candidate with "strong t-SQL and C#" skills. The position is not a senior position, but requires an experienced web developer.
What knowledge would you be looking for?
The best way to determine strength of any candidate would be to check his basics. So if someone is very strong on his basics, then he would be a strong candidate. As for questions, I believe the explaination of different kinds of JOINS would be good to start with and then later going to differences and advantages of Functions, Stored Procedures etc.
On C#, the concepts of OOPS with some sample code would be best way to test his skills.
Here are some SQL Server ones: SQL Server Quiz, Can You Answer All These?