This tutorial shows you how build a simple Node.js application with CockroachDB and Prisma.
Step 1. Start CockroachDB
Create a free cluster
- If you haven't already, sign up for a CockroachDB Cloud account.
- Log in to your CockroachDB Cloud account.
- On the Clusters page, click Create Cluster.
- On the Create your cluster page, select Serverless.
Click Create cluster.
Your cluster will be created in a few seconds and the Create SQL user dialog will display.
Create a SQL user
The Create SQL user dialog allows you to create a new SQL user and password.
- Enter a username in the SQL user field or use the one provided by default.
- Click Generate & save password.
- Copy the generated password and save it in a secure location.
Click Next.
Currently, all new users are created with full privileges. For more information and to change the default settings, see [Manage SQL users on a cluster.
Get the connection string
The Connect to cluster dialog shows information about how to connect to your cluster.
- Select General connection string from the Select option dropdown.
Open the General connection string section, then copy the connection string provided and save it in a secure location.
The sample application used in this tutorial uses system CA certificates for server certificate verification, so you can skip the Download CA Cert instructions.
Note:The connection string is pre-populated with your username, password, cluster name, and other details. Your password, in particular, will be provided only once. Save it in a secure place (Cockroach Labs recommends a password manager) to connect to your cluster in the future. If you forget your password, you can reset it by going to the SQL Users page for the cluster, found at
https://cockroachlabs.cloud/cluster/<CLUSTER ID>/users
.
- If you haven't already, download the CockroachDB binary.
Run the
cockroach start-single-node
command:$ cockroach start-single-node --advertise-addr 'localhost' --insecure
This starts an insecure, single-node cluster.
Take note of the following connection information in the SQL shell welcome text:
CockroachDB node starting at 2021-08-30 17:25:30.06524 +0000 UTC (took 4.3s) build: CCL v21.1.6 @ 2021/07/20 15:33:43 (go1.15.11) webui: http://localhost:8080 sql: postgresql://root@localhost:26257?sslmode=disable
You'll use the
sql
connection string to connect to the cluster later in this tutorial.
The --insecure
flag used in this tutorial is intended for non-production testing only. To run CockroachDB in production, use a secure cluster instead.
Step 2. Get the code
Clone the code's GitHub repo:
$ git clone https://github.com/cockroachlabs/example-app-node-prisma
Install the application dependencies:
$ cd example-app-node-prisma
$ npm install
Step 3. Initialize the database
Create a
.env
file for your project, and set theDATABASE_URL
environment variable to a valid connection string to your cluster.$ echo "DATABASE_URL=<connection-string>" >> .env
Where
<connection-string>
is the connection string you obtained earlier from the CockroachDB Cloud Console.$ echo "DATABASE_URL=postgresql://root@localhost:26257?sslmode=disable" >> .env
Note:postgresql://root@localhost:26257?sslmode=disable
is thesql
connection string you obtained earlier from thecockroach
welcome text.Prisma loads the variables defined in
.env
to the project environment. By default, Prisma uses theDATABASE_URL
environment variable as the connection string to the database.Run Prisma Migrate to initialize the database with the schema defined in
prisma/prisma.schema
.$ node_modules/.bin/prisma migrate dev --name init
You should see the following output:
Your database is now in sync with your schema. ✔ Generated Prisma Client (3.12.0 | library) to ./node_modules/@prisma/client in 73ms
This command also initializes Prisma Client to communicate with your CockroachDB cluster, based on the configuration in the
prisma/schema.prisma
file.
Step 4. Run the code
The index.js
file contains the code for INSERT
, SELECT
, UPDATE
, and DELETE
SQL operations:
const { PrismaClient } = require('@prisma/client')
const { v4: uuidv4 } = require('uuid')
const prisma = new PrismaClient({
datasources: {
db: {
url: process.env.DATABASE_URL + "&application_name=$ docs_simplecrud_node-prisma",
},
},
})
const main = async () => {
const customerIds = Array(10).fill().map(() => ({ id: uuidv4() }))
const accountValues = Array(10).fill().map((_, index) => ({
id: uuidv4(),
customer_id: customerIds[index].id,
balance: Math.floor(Math.random() * 1000)
}))
const insertCustomerRows = await prisma.customer.createMany({
data: customerIds
})
console.log('Customer rows inserted.', insertCustomerRows)
const insertAccountRows = await prisma.account.createMany({
data: accountValues
})
console.log('Account rows inserted.', insertAccountRows)
console.log('Initial Account row values:\n', await prisma.account.findMany())
const updateRows = await prisma.account.updateMany({
where: {
balance: {
gt: 100
}
},
data: {
balance: {
decrement: 5
}
}
})
console.log('Account rows updated.', updateRows)
console.log('Updated Account row values:\n', await prisma.account.findMany())
const deleteAllRows = await prisma.customer.deleteMany()
console.log('All Customer rows deleted.', deleteAllRows)
}
main()
.catch((e) => {
throw e
})
.finally(async () => {
await prisma.$disconnect()
})
In production, we recommend implementing client-side transaction retries for all database operations.
Run the application code:
$ node index.js
Customer rows inserted. { count: 10 }
Account rows inserted. { count: 10 }
Initial Account row values:
[
{
id: '1961432f-f93e-4568-b2a5-ba08f73afde5',
customer_id: '079daee3-ecf2-4a0f-980b-4c3ea4c8b6a3',
balance: 914n
},
{
id: '4ccd7eea-eb47-4aa9-9819-30b5aae58bf8',
customer_id: 'c0eeb465-ab60-4f02-9bf3-3451578d400d',
balance: 176n
},
{
id: '53ed4f7d-72ee-4390-9487-9bf318357c77',
customer_id: 'a4c9e26e-f9d8-4c1b-ac20-1aa8611b134f',
balance: 54n
},
{
id: '79a1f1b2-4050-4329-bf52-5df53fec749e',
customer_id: '392c7d15-5ab2-4149-9eee-8a3a44b36e9d',
balance: 482n
},
{
id: '7e30f1e0-e873-4565-9ea3-3079a48a4886',
customer_id: '12cb3406-264a-417c-b0e6-86593e60dc18',
balance: 478n
},
{
id: '94f461d5-3985-46c1-98f4-1896f15f0a16',
customer_id: 'e4c909a4-6683-429d-9831-dfcf792f4fb0',
balance: 240n
},
{
id: 'a0c081f5-fb15-47cc-8dbb-85c6f15677d2',
customer_id: '91ece5f2-df03-4023-b112-2b4d5677981b',
balance: 520n
},
{
id: 'a45b7c41-2f62-4620-be69-57d5d61186e4',
customer_id: 'c1824327-d6a1-4916-a666-ea157ef2a409',
balance: 50n
},
{
id: 'dbe0dec5-257b-42ff-9d36-1b5a57e1a4ac',
customer_id: '6739eb2f-bcb1-4074-aab4-5860b04d227d',
balance: 468n
},
{
id: 'ebc520b4-8df0-4e2f-8426-104594f6341c',
customer_id: 'f83e02cb-77cf-4347-9e0c-28cad65fac34',
balance: 336n
}
]
Account rows updated. { count: 8 }
Updated Account row values:
[
{
id: '1961432f-f93e-4568-b2a5-ba08f73afde5',
customer_id: '079daee3-ecf2-4a0f-980b-4c3ea4c8b6a3',
balance: 909n
},
{
id: '4ccd7eea-eb47-4aa9-9819-30b5aae58bf8',
customer_id: 'c0eeb465-ab60-4f02-9bf3-3451578d400d',
balance: 171n
},
{
id: '53ed4f7d-72ee-4390-9487-9bf318357c77',
customer_id: 'a4c9e26e-f9d8-4c1b-ac20-1aa8611b134f',
balance: 54n
},
{
id: '79a1f1b2-4050-4329-bf52-5df53fec749e',
customer_id: '392c7d15-5ab2-4149-9eee-8a3a44b36e9d',
balance: 477n
},
{
id: '7e30f1e0-e873-4565-9ea3-3079a48a4886',
customer_id: '12cb3406-264a-417c-b0e6-86593e60dc18',
balance: 473n
},
{
id: '94f461d5-3985-46c1-98f4-1896f15f0a16',
customer_id: 'e4c909a4-6683-429d-9831-dfcf792f4fb0',
balance: 235n
},
{
id: 'a0c081f5-fb15-47cc-8dbb-85c6f15677d2',
customer_id: '91ece5f2-df03-4023-b112-2b4d5677981b',
balance: 515n
},
{
id: 'a45b7c41-2f62-4620-be69-57d5d61186e4',
customer_id: 'c1824327-d6a1-4916-a666-ea157ef2a409',
balance: 50n
},
{
id: 'dbe0dec5-257b-42ff-9d36-1b5a57e1a4ac',
customer_id: '6739eb2f-bcb1-4074-aab4-5860b04d227d',
balance: 463n
},
{
id: 'ebc520b4-8df0-4e2f-8426-104594f6341c',
customer_id: 'f83e02cb-77cf-4347-9e0c-28cad65fac34',
balance: 331n
}
]
All Customer rows deleted. { count: 10 }
What's next?
Read more about using Prisma Client.
You might also be interested in the following pages: