Database Systems

Core Concepts

Query planning

Cost estimation

• measured in terms of I/I or CPU costs
• based on pre-computed stats and an estimate of the cardinality of query output

Relational equivalences that define a search space

Cost-based search

• uses a DP algorithm to construct a plan for the query

Concurrency control

Multi-granularity locking

Multiple lock modes

Database recovery

Distribution

References

Readings in Database Systems (the Red Book)