Interview questions

Went to a few interview recently. Below are the questions I can remember. Compared to four years ago when I was looking for my first job, the questions this time are more conceptual in nature, and companies focus a lot more on behavior and situational questions.

C#

• Difference between value and reference type 
• Difference between ref and out
• Where do you use using
• How to use datareader
• How to fill a dataset using data adapter
• How to read a text file 
• Design patterns: factory, abstract etc
• Delegates. What's it for, when to use it.

JavaScript/jQuery

• How to create objects in JavaScript

Database

• Difference between IDENTITY and SCOPE_IDENTITY
• How to know number of rows in a table
• What's ACID
• Define third normal form (3NF) 
• UNION vs UNION ALL
• A quick test on Join tables
• paging in stored procedure
• efficient way to send a list of id to stored procedure and parse. Passing a delimited list then use CTE for this.

WebServices and WCF

• Where's the end-point information in WSDL file
• How to implement a webservice using WCF. Answer: define an interface and decorate with [OperationContract] attribute, then implement the interface.