MongoDB find() method Tutorial
The MongoDB find() method is a query opetation method to retrieve documents from a collection.
Basic Document Retrieval
MongoDB find() method is used to retrieve all documents in a collection.
db.myCollection.find();
Limit the Number of Results
The limit() to restrict the number of documents returned.
db.myCollection.find().limit(5);
Filtering by Field
Specify the filter criteria within the find() method to match documents.
db.myCollection.find({ age: 25 });
Logical Operators
Use $and, $or, and other logical operators for complex queries.
db.myCollection.find({ $or: [{ age: 25 }, { name: "Alice" }] });
Projection
The projection to limit the fields returned in the result.
db.myCollection.find({}, { name: 1, age: 1, _id: 0 });
Sorting Results
We can sort MongoDB documents using sort(), specifying fields and order.
db.myCollection.find().sort({ age: 1 }); // Ascending order
Counting Documents
The count() to get the number of matching documents.
db.myCollection.find({ age: 30 }).count();
Limit Fields in Result
The MongoDB findOne() to retrieve the first matching document.
db.myCollection.findOne({ age: 30 }, { name: 1, age: 1, _id: 0 });
Regular Expressions
The regex for pattern-based searches in field values.
db.myCollection.find({ name: /^J/ }); // Names starting with 'J'
Nested Document Search
Search within nested documents or arrays using dot notation.
db.myCollection.find({ "address.city": "New York" });