MongoDB

Overview

MongoDB is a document-oriented NoSQL database that stores data in flexible, JSON-like documents. Zequel provides full support for MongoDB through the official mongodb driver (v7.0.0).

Supported Versions

MongoDB 4.4+
MongoDB 5.0+
MongoDB 6.0+
MongoDB 7.0+
MongoDB Atlas (cloud)

Connection

Standard Connection

Host: localhost
Port: 27017
Database: admin
Username: (optional)
Password: (optional)

Connection String (URI)

MongoDB supports connection URIs:

mongodb://localhost:27017
mongodb://user:password@localhost:27017/database
mongodb+srv://cluster.mongodb.net/database  # MongoDB Atlas

You can paste a full MongoDB connection string into the Database field, and Zequel will use it directly.

Authentication

Default authentication database is admin:

{
  host: 'localhost',
  port: 27017,
  database: 'myapp',
  username: 'myuser',
  password: 'mypassword'
  // Automatically adds: ?authSource=admin
}

SSL/TLS Configuration

MongoDB supports TLS connections:

{
  host: 'cluster.mongodb.net',
  ssl: true,
  sslConfig: {
    rejectUnauthorized: true,
    ca: fs.readFileSync('ca.pem')
  }
}

MongoDB Query Language

Zequel supports MongoDB’s native query syntax:

Collection Operations

// Find documents
db.users.find({age: {$gt: 18}})
db.users.findOne({email: "[email protected]"})

// Insert documents
db.users.insertOne({name: "Alice", age: 30, email: "[email protected]"})
db.users.insertMany([{name: "Bob"}, {name: "Charlie"}])

// Update documents
db.users.updateOne({name: "Alice"}, {$set: {age: 31}})
db.users.updateMany({status: "inactive"}, {$set: {archived: true}})

// Delete documents
db.users.deleteOne({_id: ObjectId("...")}
)
db.users.deleteMany({status: "deleted"})

// Count documents
db.users.countDocuments({status: "active"})

// Distinct values
db.users.distinct("country", {status: "active"})

Aggregation Pipeline

db.orders.aggregate([
  {$match: {status: "completed"}},
  {$group: {
    _id: "$customer_id",
    total: {$sum: "$amount"},
    count: {$sum: 1}
  }},
  {$sort: {total: -1}},
  {$limit: 10}
])

Index Operations

// Create index
db.users.createIndex({email: 1}, {name: "idx_email", unique: true})
db.users.createIndex({location: "2dsphere"})  // Geospatial index

// Drop index
db.users.dropIndex("idx_email")

Collection Management

// Drop collection
db.users.drop()

// Get collection names
db.getCollectionNames()

// Database stats
db.stats()

Features

Collections (Tables)

Create and drop collections
Rename collections
View collection statistics
Document count estimation

Documents (Rows)

MongoDB stores data as BSON documents:

{
  "_id": ObjectId("507f1f77bcf86cd799439011"),
  "name": "Alice",
  "age": 30,
  "email": "[email protected]",
  "address": {
    "street": "123 Main St",
    "city": "New York"
  },
  "tags": ["developer", "remote"],
  "created_at": ISODate("2024-01-01T00:00:00Z")
}

Data Types

MongoDB BSON types:

Basic
Special
Complex

String
Number (Int32, Int64, Double)
Boolean
Null

Indexes

Single field: {field: 1} (ascending) or {field: -1} (descending)
Compound: {field1: 1, field2: -1}
Unique: Prevent duplicate values
TTL: Auto-delete documents after time
Text: Full-text search
2dsphere: Geospatial queries
Hashed: Hash-based sharding

// TTL index - auto-delete after 30 days
db.sessions.createIndex(
  {createdAt: 1},
  {expireAfterSeconds: 2592000}
)

// Text index for search
db.articles.createIndex({title: "text", content: "text"})
db.articles.find({$text: {$search: "mongodb"}})

Schema Validation (Optional)

Enforce document structure:

db.createCollection("users", {
  validator: {
    $jsonSchema: {
      bsonType: "object",
      required: ["name", "email"],
      properties: {
        name: {
          bsonType: "string",
          description: "must be a string and is required"
        },
        email: {
          bsonType: "string",
          pattern: "^.+@.+$",
          description: "must be a valid email"
        },
        age: {
          bsonType: "int",
          minimum: 0,
          description: "must be a positive integer"
        }
      }
    }
  }
})

Schema-less Operations

MongoDB is schema-less, so traditional SQL operations work differently:

Adding Fields

Fields are added automatically when documents are inserted:

// Add new field to all documents
db.users.updateMany({}, {$set: {status: "active"}})

Removing Fields

// Remove field from all documents
db.users.updateMany({}, {$unset: {old_field: ""}})

Zequel provides a UI for these operations.

Renaming Fields

// Rename field in all documents
db.users.updateMany({}, {$rename: {old_name: "new_name"}})

MongoDB-Specific Features

Change Streams

Watch for real-time changes (requires replica set):

const changeStream = db.users.watch();
changeStream.on('change', (change) => {
  console.log(change);
});

Transactions (4.0+)

Multi-document ACID transactions:

const session = client.startSession();
session.startTransaction();
try {
  db.accounts.updateOne({_id: 1}, {$inc: {balance: -100}}, {session});
  db.accounts.updateOne({_id: 2}, {$inc: {balance: 100}}, {session});
  await session.commitTransaction();
} catch (error) {
  await session.abortTransaction();
} finally {
  session.endSession();
}

GridFS

Store large files (> 16MB):

const bucket = new mongodb.GridFSBucket(db);
fs.createReadStream('large-file.pdf')
  .pipe(bucket.openUploadStream('large-file.pdf'));

Views

Create read-only views with aggregation pipelines:

// Create view in Zequel
{
  "source": "orders",
  "pipeline": [
    {"$match": {"status": "completed"}},
    {"$group": {
      "_id": "$customer_id",
      "total": {"$sum": "$amount"}
    }}
  ]
}

Time Series Collections (5.0+)

db.createCollection("weather", {
  timeseries: {
    timeField: "timestamp",
    metaField: "sensor_id",
    granularity: "hours"
  }
})

Users & Security

Manage MongoDB users:

// Create user
db.createUser({
  user: "appuser",
  pwd: "password",
  roles: [{role: "readWrite", db: "myapp"}]
})

// Drop user
db.dropUser("appuser")

// View users
db.getUsers()

Limitations

MongoDB is schema-less, so some traditional RDBMS features don’t apply:

No foreign keys: Relationships are managed in application code
No joins (use $lookup in aggregation pipeline instead)
No stored procedures: Use application logic
No triggers: Use Change Streams for reactive behavior
Document size limit: 16MB per document
Field name restrictions: Cannot start with $ or contain .

Best Practices

Design for your queries
- Embed related data for fast reads
- Use references for large or frequently changing data
Use indexes wisely
- Index fields used in queries
- Monitor index usage with explain()
- Drop unused indexes
Avoid large documents
- Keep documents under 16MB
- Use GridFS for large files

Use projection

// Only fetch needed fields
db.users.find({}, {name: 1, email: 1, _id: 0})

Use aggregation pipeline for complex queries

db.orders.aggregate([
  {$match: {status: "shipped"}},
  {$lookup: {
    from: "customers",
    localField: "customer_id",
    foreignField: "_id",
    as: "customer"
  }}
])

Enable authentication in production
```
mongod --auth
```

Docker Development

Zequel includes MongoDB in Docker Compose:

services:
  mongodb:
    image: mongo:7.0
    ports:
      - "27017:27017"
    environment:
      MONGO_INITDB_ROOT_USERNAME: root
      MONGO_INITDB_ROOT_PASSWORD: mongodb
    volumes:
      - ./docker/mongodb/init.js:/docker-entrypoint-initdb.d/init.js

Supported Databases

Overview

Supported Versions

Connection

Standard Connection

Connection String (URI)

Authentication

SSL/TLS Configuration

MongoDB Query Language

Collection Operations

Aggregation Pipeline

Index Operations

Collection Management

Features

Collections (Tables)

Documents (Rows)

Data Types

Indexes

Schema Validation (Optional)

Schema-less Operations

Adding Fields

Removing Fields

Renaming Fields

MongoDB-Specific Features

Change Streams

Transactions (4.0+)

GridFS

Views

Time Series Collections (5.0+)

Users & Security

Limitations

Best Practices

Docker Development

Additional Resources

Build docs developers (and LLMs) love

Supported Databases

​Overview

​Supported Versions

​Connection

​Standard Connection

​Connection String (URI)

​Authentication

​SSL/TLS Configuration

​MongoDB Query Language

​Collection Operations

​Aggregation Pipeline

​Index Operations

​Collection Management

​Features

​Collections (Tables)

​Documents (Rows)

​Data Types

​Indexes

​Schema Validation (Optional)

​Schema-less Operations

​Adding Fields

​Removing Fields

​Renaming Fields

​MongoDB-Specific Features

​Change Streams

​Transactions (4.0+)

​GridFS

​Views

​Time Series Collections (5.0+)

​Users & Security

​Limitations

​Best Practices

​Docker Development

​Additional Resources

Build docs developers (and LLMs) love

Overview

Supported Versions

Connection

Standard Connection

Connection String (URI)

Authentication

SSL/TLS Configuration

MongoDB Query Language

Collection Operations

Aggregation Pipeline

Index Operations

Collection Management

Features

Collections (Tables)

Documents (Rows)

Data Types

Indexes

Schema Validation (Optional)

Schema-less Operations

Adding Fields

Removing Fields

Renaming Fields

MongoDB-Specific Features

Change Streams

Transactions (4.0+)

GridFS

Views

Time Series Collections (5.0+)

Users & Security

Limitations

Best Practices

Docker Development

Additional Resources