Tuesday, August 6, 2013

empty values in WCF DataContract

could be caused by forgetting DataMember attribute

Some Basic SQL interview questions for .net developers


  • what is the difference between a union and a join?
  • if you have a simple table of people with amounts of money - how would you get the name of the 2nd highest owner?
  • how would you get the 2nd highest amount?
  • if you have a table with name company amount and you you want to have sums per company how would you filter companies with 0 and null amounts ? 
  • what is the difference between where and having?
  • what is the difference between exists and a join?
  • How would you create a database that needed to store a user name, password, and 2 phone numbers?
  • What are some of the ways you can ensure unique data in a table?
  • What is a CTE (common table expression) and when can it be used?
  •  What would be the first few things you would check to try to improve a SQL call that is taking a long time to run?



Visual Studio Reference issues

sometimes the using statement wont fail even though there is no reference

this happened to me with
using System.Runtime.Serialization;
which did not fail