MongoDB Tutorials

MongoDB from a first document to a schema you can defend in review — documents and BSON types, CRUD and query operators, when to embed and when to reference, indexes and the ESR rule, the aggregation pipeline, transactions, replication, change streams and Spring Data. Every example is taken from a real short-video CMS, and the measurements come from the machine that wrote them rather than from a marketing page.

• MongoDB – Spring Data MongoDB
  The Java side: repositories versus MongoTemplate, how mapping works, where to declare indexes, and the field rename that catches everyone.
• MongoDB – Which Applications Actually Fit
  Five shapes of application MongoDB suits well, and four where choosing it is a decision you will be undoing later.
• MongoDB – Change Streams and Time-Series
  Tail the oplog to push live updates to a browser, and see what a time-series collection measurably does and does not save.
• MongoDB – Replication and Sharding
  Replica sets, the oplog, read preference and write concern — and an honest look at when sharding is the answer and when it is not.
• MongoDB – Atomicity and Transactions
  Single-document atomicity covers more than you would think. What multi-document transactions cost, and when you genuinely need one.
• MongoDB – $lookup, $unwind and $facet
  Joining collections in an aggregation, flattening arrays, running several pipelines at once — and the strict type match that makes a join return nothing.
• MongoDB – The Aggregation Pipeline
  The mental model: documents flowing through stages. $match, $group, $sort, $project — and why stage order decides your query plan.
• MongoDB – Text Search
  Text indexes and field weights, the one-per-collection limit, and the point where you should stop and reach for a real search engine.
• MongoDB – Indexes and the ESR Rule
  Single, compound, multikey, unique and partial indexes, the field order that makes them work, and how to read explain().
• MongoDB – Schema Validation
  $jsonSchema, validation levels and actions — and why a flexible store still wants rules at the boundary.
• MongoDB – Data Modeling: Embed or Reference
  The one decision that shapes every MongoDB schema, with the 16 MB limit, unbounded growth and the real cost of denormalization.
• MongoDB – Query Operators
  Comparison, logical, element and array operators, plus projection — the vocabulary every later query is built from.
• MongoDB – CRUD Operations
  insertOne through deleteMany, upserts and bulk writes, and why an update should touch one field rather than rewrite a document.
• MongoDB – Documents and BSON Types
  Documents, the BSON type system, _id and ObjectId — and the string-versus-ObjectId mismatch that silently breaks joins.
• MongoDB – Installation and mongosh
  Get a MongoDB running in Docker, connect with mongosh, and understand why this track runs a replica set from the very first command.
• MongoDB – Why NoSQL, and When Not To
  What a document store actually buys you, what it costs, and the four cases where a relational database is still the right answer.