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dbms and data modeling

focus on relational and nosql databases, er diagrams, normalization, indexing, transactions, and query optimization.

key concepts

  • er diagrams and normalization
  • acid properties, isolation levels
  • oltp vs olap
  • indexing strategies: b+tree, hash index
  • nosql dbs: redis, mongodb, cassandra, neo4j

projects

1. postgres analytics schema

  • transactional db + star schema for analytics

2. nosql replication

  • same dataset in mongodb, compare queries

3. mini db engine

  • python dict + file i/o + simple sql parser

4. query planner visualizer

  • explain plan + cost estimation demo