Topic
Database
Learn Database as a connected topic across chapters, concepts, simulations, and interview reasoning.
10 Concepts48 Articles17h 51m
Overview
Learn Database as a connected topic across chapters, concepts, simulations, and interview reasoning.
How this topic helps
System Design
Distributed Systems
Databases
Transactions
Learning Path in this Topic
Series that contain articles from Database. Select a path to filter the article list.
Articles
48 matched articles
Article 1CosmosDB Partition Internals: Logical vs Physical Partitions Explained🔥 When Your Database Bill Triples Overnight
A retail engineering team ships a flash-sale feature. Traffic spikes 10×. Their Azure CosmosDB bill triples within 24 hours. Queries that ran in 5ms now ta16 minArticle 2Azure Cosmos DB Consistency Levels Explained: Strong, Bounded Staleness, Session, Consistent Prefix, and EventualTLDR: Cosmos DB offers five consistency levels — Strong, Bounded Staleness, Session, Consistent Prefix, Eventual — each with precise, non-obvious internal mechanics. Session does not mean HTTP session25 minArticle 3Azure Cosmos DB API Modes Explained: NoSQL, MongoDB, Cassandra, PostgreSQL, Gremlin, and TableTLDR: Cosmos DB's six API modes are wire-protocol compatibility layers over one shared ARS storage engine — except PostgreSQL (Citus), which is genuinely different. Every API emulates its native datab24 minArticle 4LLD for URL Shortener: Designing TinyURLTLDR
TLDR: A URL Shortener maps long URLs to short IDs. The core challenge is generating a globally unique, short, collision-free ID at scale. We use Base62 encoding on auto-incrementing database IDs22 min
Article 5Types of Locks Explained: Optimistic vs. Pessimistic LockingTLDR: Pessimistic locking locks the record before editing — safe but slower under low contention. Optimistic locking checks for changes before saving using a version number — fast but can fail and req13 min
Article 6Compare-and-Swap and Optimistic Locking: How Every Database Implements ItTLDR: Compare-and-Swap (CAS) is the CPU-level atomic instruction that makes lock-free concurrency possible. Optimistic locking builds on it at the database layer: read freely, compute locally, write o34 minPage 1 of 8