Advanced Querying in MongoDB: Operators and Pattern Matching
Advanced Querying in MongoDB: Operators and Pattern Matching
Advanced querying in MongoDB allows for more complex and flexible data retrieval. This post explores various operators and techniques for querying MongoDB effectively.
Using Operators:
Comparison Operators:
// Greater Than ($gt)
> db.myCollection.find({ age: { $gt: 25 } })
//Less Than ($lt)
> db.myCollection.find({ age: { $lt: 30 } })
//Equal To ($eq)
> db.myCollection.find({ name: { $eq: "Alice" } })
Logical Operators:
//AND ($and)
> db.myCollection.find({ $and: [{ age: { $gt: 20 } }, { age: { $lt: 30 } }] })
//OR ($or)
> db.myCollection.find({ $or: [{ name: "Alice" }, { name: "Bob" }] })
Element Operators:
//Exists ($exists)
> db.myCollection.find({ age: { $exists: true } })
Array Operators:
//In ($in)
> db.myCollection.find({ name: { $in: ["Alice", "Bob"] } })
//Size ($size)
> db.myCollection.find({ items: { $size: 3 } })
Regular Expressions and Pattern Matching:
//Exact Match
> db.myCollection.find({ name: /Alice/ })
//Case-Insensitive Search
> db.myCollection.find({ name: /alice/i })
MongoDB advanced querying, MongoDB operators, MongoDB pattern matching, MongoDB regular expressions, MongoDB comparison operators, MongoDB logical operators.
