Basically, It was mass hiring So the only way to filter is by the Written test. So you need to have good knowledge of Quants, Logical Reasoning and Verbal(Important one ).
In written test they have three sections Quants, Logical reasoning and Verbal. And the students are filtered as per cut-off of each section and that would be 50% for every section, most of the time.
Once you have cleared the written round, next round would be Technical and HR. In this round, they ask only basic technical questions related to DBMS, OS and from your Resume and some basic HR questions. All they want is good communication skill and your confidence.