# CMU 15-445/645 Database Systems

- [Relational Data Model](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/relational-data-model.md)
- [Advanced SQL](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/advanced-sql.md): 本节介绍 SQL 的部分复杂用法
- [Database Storage](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/database-storage.md): 数据库存储层
- [Buffer Pools](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/buffer-pools.md)
- [Hash Tables](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/hash-tables.md)
- [Tree Indexes](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/tree-indexes.md)
- [Index Concurrency Control](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/index-concurrency-control.md)
- [Query Processing](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/query-processing.md)
- [Sorting\&Aggregations](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/sorting-and-aggregations.md)
- [Join Algorithms](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/join-algorithms.md)
- [Query Optimization](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/query-optimization.md)
- [Parallel Execution](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/parallel-execution.md)
- [Embedded Database Logic](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/embedded-database-logic.md)
- [Concurrency Control Theory](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/concurrency-control-theory.md)
- [Two Phase Locking](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/two-phase-locking.md)
- [Timestamp Ordering Concurrency Control](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/timestamp-ordering-concurrency-control.md)
- [Multi-Version Concurrency Control](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/multi-version-concurrency-control.md)
- [Logging Schemes](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/logging-schemes.md)
- [Database Recovery](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/database-recovery.md)
- [Introduction to Distributed Databases](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/introduction-to-distributed-databases.md)
- [Distributed OLTP Databases](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/distributed-oltp-databases.md)
- [Distributed OLAP Databases](https://zhenghe.gitbook.io/open-courses/cmu-15-445-645-database-systems/distributed-olap-databases.md)


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