How prisma knows which database to connect to

Prisma connects to the database based on the configuration you provide in the datasource block of your schema.prisma file. Here’s how Prisma determines which database to connect to:

Configuration in schema.prisma

In your schema.prisma file, you specify the database connection details within the datasource block. This includes the database provider and the connection URL or other relevant configuration parameters.

Example schema.prisma

// schema.prisma

datasource db {
  provider = "postgresql"
  url      = env("DATABASE_URL")
}

Components of Configuration:

1. Provider (provider):

   • Specifies the type of database you are connecting to, such as postgresql, mysql, sqlite, etc. Prisma supports various database providers, and the provider name determines which database driver Prisma uses to connect to your database.

2. Connection URL (url):

   • Specifies the connection URL or connection parameters required to connect to your database. This URL typically includes details like the database host, port, username, password, and database name.

3. Environment Variables (env()):

   • You can use the env() function to load sensitive information like database URLs from environment variables. This is a best practice for managing sensitive information securely in different environments (development, staging, production).

Using Environment Variables

It’s common practice to use environment variables for sensitive data like database credentials. For example, you might set an environment variable named DATABASE_URL with your database connection string:

export DATABASE_URL="postgresql://username:password@localhost:5432/mydatabase"

In your schema.prisma, you would reference this environment variable:

// schema.prisma

datasource db {
  provider = "postgresql"
  url      = env("DATABASE_URL")
}