I have received a very simple but interesting question by one of my earlier clients about how to count NULL values from the column.
Recently during the consulting engagement, I needed to create a query that Lists All the Nullable Columns in Database, which I am sharing.
A Very popular question I often here whenever I am presenting at the developer conference – How to Change Column Property From NULL to Not NULL Value?
Today, we will see a very interesting puzzle about data types and default values.
You need to answer-
1 The original datatype A and default value B
2 The new datatype C and new default value D
Question: How Default Value and Nullable Column works together for a single table?
This is a very interesting question. I really do not know why interviews are fascinated with this question. One of the professional services I offer is to help organizations select an ideal employee for their organization and last week, I was on a conference call with a large MNC who was looking for performance tuning expert for their organization. We interviewed around 50 different employees and offered jobs to 2 experts and 1 has so far accepted it. One of the questions which I see my friends from the interview panel asking again and again was about Primary Key. I noticed that most of the candidate got it correct.