Connecting and disconnecting

Calling $connect() explicitly

If you need the first request to respond instantly and cannot wait for a lazy connection to be established, you can explicitly call prisma.$connect() to establish a connection to the data source:

const prisma = new PrismaClient()

// run inside `async` function
await prisma.$connect()

Calling $disconnect() explicitly

One scenario where you should call $disconnect() explicitly is where a script:

1. Runs infrequently (for example, a scheduled job to send emails each night), which means it does not benefit from a long-running connection to the database and
2. Exists in the context of a long-running application, such as a background service. If the application never shuts down, Prisma Client never disconnects.

The following script creates a new instance of PrismaClient, performs a task, and then disconnects - which closes the connection pool:

import { PrismaClient } from '@prisma/client'

const prisma = new PrismaClient()
const emailService = new EmailService()

async function main() {
  const allUsers = await prisma.user.findMany()
  const emails = allUsers.map((x) => x.email)

  await emailService.send(emails, 'Hello!')
}

main()
  .then(async () => {
    await prisma.$disconnect()
  })
  .catch(async (e) => {
    console.error(e)
    await prisma.$disconnect()
    process.exit(1)
  })

If the above script runs multiple times in the context of a long-running application without calling $disconnect(), a new connection pool is created with each new instance of PrismaClient.