How is data stored on disk?
Types of indexes
Clustered vs Unclustered, Sparse vs Dense
Composite Indexes, Why attribute order matters
B+ Trees (How are they different/better than B-Trees),
Buckets vs disk blocks
When and how do indexes help with Table Joins.
What is UTF-8 how is it different than ASCII?
How does a DB decide what physical algorithms to run?
Cost Parameters, M, T, B, V
When can sorting, hashing, indexing help? How do we estimate this?
Rules based optimization
Push down Optimization
Pull up, Push Down Optimization
Cost based optimization
Calculating a query plan cost
What are they, why are they important?
Serial Schedules vs Serializable Schedules
2PL to enforce Isolation and serializability
How is the log written under various regimes:
What are the differences in recovery?
How does checkpointing work in the log
What is (non)quiescent checkpointing? How does it work?
Distributed Storage Systems
How does Hadoop split apart large files?
Why is replication important? Be able to perform an example.
What happens when a node in HDFS fails? What happens when an entire rack goes down?
What are the inputs and outputs of the mapper?
What are the inputs and outputs of the reducer?
What does the MapReduce subsystem do in between map and reduce?
How can Map Reduce be used to answer large SQL queries
Be able to design a map reduce program (pseudocode) that performs some SQL function
Describe the CAP theorem, name some databases that might apply to the different regimes
Why do columnar databases store their data in columns, and why is that congruent with HDFS?
What is SPARK? How is it different from MapReduce/HDFS systems?