Elaborate on a challenging project you undertook. How do you optimise queries? How do you optimise/monitor data quality in ETL? What kind of performance/hardware tuning can be done in a postgres db? OLAP vs OLTP? What is Kafka? Explain the architecture? Explain the distributed and fault tolerance characteristics? How does kakfa store committed offsets for the partitions? What is the role of Zookeeper in this?
