I applied through a staffing agency. I interviewed at Fiserv (Nenagh)
Interview
First was a very simple SQL based test consisting of few questions.
The second was telephone round mostly focused on experience with handling big data.
Finally was the on-site round with a complete workshop of writing SQL and making a presentation.
Interview questions [1]
Question 1
All were simple SQL based questions. The only thing is to focus more on your SQL joins during the workshop. They will give you many to many relationship tables so you can end up creating duplicates.