What is the mongodb query statement called?

Use the find() statement in MongoDB to query and filter documents based on query conditions. Syntax: db.collection.find(query, projection). Parameters include optional query conditions (query) and return fields (projection). Usage: Find all documents, conditional search, specify return fields, paging queries, sort results, find array documents, use regular expressions and logical operators for complex queries.

MongoDB Query Statement

MongoDB uses a query statement called find() Retrieve documents in a collection.

Syntax

<code>db.collection.find(query, projection)</code>

Parameters

• query (optional): used for Query parameters to filter results, such as { name: "John" }.
• projection (optional): is used to specify which fields in the document are to be returned, for example { name: 1, age: 1 }.

Usage

1. Find all documents

<code>db.collection.find()</code>

2. Find documents based on conditions

<code>db.collection.find({ name: "John" })</code>

3. Specify the return field

<code>db.collection.find({}, { name: 1, age: 1 })</code>

4. Paging query

<code>db.collection.find().skip(10).limit(5)</code>

5. Sort Result

<code>db.collection.find().sort({ name: 1 }) // Ascending order
db.collection.find().sort({ name: -1 }) // Descending order</code>

6. Find the array in the document

<code>db.collection.find({"arrayField.field": "value"})</code>

7. Use regular expression

<code>db.collection.find({ name: /John/i }) // case-insensitive match</code>

8. Use logical operators

<code>db.collection.find({ $and: [{ name: "John" }, { age: { $gt: 18 }}] }) // AND operator</code>

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