Orionjs provides a flexible system for configuring and managing MongoDB connections. This allows you to connect to multiple MongoDB instances or databases as needed.

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Default Connection

By default, Orionjs will look for a MongoDB connection string in the MONGO_URL or env.mongo_url environment variable. This is the simplest way to get started: 
// In your environment configuration
MONGO_URL=mongodb://localhost:27017/my-database
You don’t need any additional code to use the default connection - all collections will use it automatically unless specified otherwise.

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Connection Initialization

Connections are not started until you call any method in a collection or explicitly call startConnection on the collection. This lazy initialization prevents unnecessary connections when a collection is defined but not used. 
// Connection will be initialized when using the collection
const user = await users.findOne({ _id: 'user-123' })

// Or you can explicitly start the connection
await users.startConnection()