NO Sql

What is NoSQL? Differences between SQL and NoSQL CAP theorem (Consistency, Availability, Partition Tolerance) BASE vs ACID Horizontal scaling and sharding basics Four main types of NoSQL databases: Document, Key-Value, Columnar, Graph Use cases where NoSQL is preferred

MongoDB overview and document model BSON format Collections vs Tables Schema design in MongoDB CRUD operations using find, insertOne, updateOne, deleteOne Querying nested fields and arrays Indexes in MongoDB Aggregation pipeline Transactions in MongoDB Replication and sharding in MongoDB

Key-value model explained Redis data structures: strings, lists, sets, hashes, sorted sets Expiry and TTL in Redis Pub/Sub, pipelines, and Lua scripting Redis persistence: RDB, AOF DynamoDB basics: partitions, partition keys, sort keys DynamoDB read/write throughput and autoscaling Consistency models in DynamoDB (eventual vs strong consistency)

Handle high-throughput, write-optimized distributed workloads. Column-family structure (rows, partitions, clustering columns) Cassandra data model and CQL (Cassandra Query Language) Partitioning and data distribution (consistent hashing) Tunable consistency in Cassandra (QUORUM, ONE, ALL) Replication and replication factor Write path and read path in Cassandra HBase architecture (RegionServers, HMaster) Use cases: time-series data, analytics platforms

Model and query complex relationships using graph theory. "What is a graph database and where would you use it?" "How is Cypher query language different from SQL?" Topics: Nodes, relationships, properties Use cases: social networks, fraud detection, recommendation systems Neo4j and the Cypher query language Querying patterns and traversals Indexes and constraints in Neo4j Amazon Neptune overview Graph algorithms: shortest path, PageRank, centrality

Know when to combine SQL and NoSQL for the right architectural fit. Sample Interview Questions: "What is polyglot persistence and why is it useful?" "How would you design a system using both MongoDB and PostgreSQL?" Topics: Polyglot persistence: definition and benefits Choosing the right database per component Example architecture: product catalog in MongoDB + orders in PostgreSQL Event sourcing with NoSQL stores Data synchronization between SQL and NoSQL Best practices for multi-datab

Master how NoSQL databases scale and perform under high load. "How do you scale MongoDB horizontally?" "What are the trade-offs between consistency and availability in Cassandra?" Read/write scaling strategies Sharding vs replication Consistency models per database type Caching strategies (Redis, DynamoDB DAX) Indexing and performance tuning Data modeling strategies (denormalization, access patterns) Write amplification and compaction

Apply NoSQL to build scalable, real-world systems. "Design a high-scale chat application using NoSQL databases." "How would you store and retrieve user sessions efficiently?" Designing a messaging app (Redis pub/sub, MongoDB for message history) Session management using Redis E-commerce catalog using MongoDB IoT data ingestion using Cassandra Graph-based recommendations using Neo4j Cost vs performance trade-offs (e.g., DynamoDB vs MongoDB Atlas)