PostgreSQL

The PostgreSQL data source connector connects Prisma ORM to a database server.

By default, the PostgreSQL connector contains a database driver responsible for connecting to your database. You can use a driver adapter (Preview) to connect to your database using a JavaScript database driver from Prisma Client.

Example

To connect to a PostgreSQL database server, you need to configure a datasource block in your Prisma schema file:

schema.prisma
1datasource db {
2 provider = "postgresql"
3 url = env("DATABASE_URL")
4}

The fields passed to the datasource block are:

Using the node-postgres driver

As of , you can use Prisma ORM with database drivers from the JavaScript ecosystem (instead of using Prisma ORM's built-in drivers). You can do this by using a driver adapter.

For PostgreSQL, (pg) is one of the most popular drivers in the JavaScript ecosystem. It can be used with any PostgreSQL database that's accessed via TCP.

This section explains how you can use it with Prisma ORM and the @prisma/adapter-pg driver adapter.

1. Enable the driverAdapters Preview feature flag

Since driver adapters are currently in Preview, you need to enable its feature flag on the datasource block in your Prisma schema:

// schema.prisma
generator client {
provider = "prisma-client-js"
previewFeatures = ["driverAdapters"]
}
datasource db {
provider = "postgresql"
url = env("DATABASE_URL")
}

Once you have added the feature flag to your schema, re-generate Prisma Client:

$npx prisma generate

2. Install the dependencies

Next, install the pg package and Prisma ORM's driver adapter:

$npm install pg
$npm install @prisma/adapter-pg

3. Instantiate Prisma Client using the driver adapter

Finally, when you instantiate Prisma Client, you need to pass an instance of Prisma ORM's driver adapter to the PrismaClient constructor:

import { Pool } from 'pg'
import { PrismaPg } from '@prisma/adapter-pg'
import { PrismaClient } from '@prisma/client'
const connectionString = `${process.env.DATABASE_URL}`
const pool = new Pool({ connectionString })
const adapter = new PrismaPg(pool)
const prisma = new PrismaClient({ adapter })

Notice that this code requires the DATABASE_URL environment variable to be set to your PostgreSQL connection string. You can learn more about the connection string below.

Connection details

Connection URL

Prisma ORM follows the connection URL format specified by , but does not support all arguments and includes additional arguments such as schema. Here's an overview of the components needed for a PostgreSQL connection URL:

Structure of the PostgreSQL connection URL

Base URL and path

Here is an example of the structure of the base URL and the path using placeholder values in uppercase letters:

postgresql://USER:PASSWORD@HOST:PORT/DATABASE

The following components make up the base URL of your database, they are always required:

NamePlaceholderDescription
HostHOSTIP address/domain of your database server, e.g. localhost
PortPORTPort on which your database server is running, e.g. 5432
UserUSERName of your database user, e.g. janedoe
PasswordPASSWORDPassword for your database user
DatabaseDATABASEName of the you want to use, e.g. mydb

You must percentage-encode special characters.

Arguments

A connection URL can also take arguments. Here is the same example from above with placeholder values in uppercase letters for three arguments:

postgresql://USER:PASSWORD@HOST:PORT/DATABASE?KEY1=VALUE&KEY2=VALUE&KEY3=VALUE

The following arguments can be used:

Argument nameRequiredDefaultDescription
schemaYespublicName of the you want to use, e.g. myschema
connection_limitNonum_cpus * 2 + 1Maximum size of the connection pool
connect_timeoutNo5Maximum number of seconds to wait for a new connection to be opened, 0 means no timeout
pool_timeoutNo10Maximum number of seconds to wait for a new connection from the pool, 0 means no timeout
sslmodeNopreferConfigures whether to use TLS. Possible values: prefer, disable, require
sslcertNoPath of the server certificate. Certificate paths are resolved relative to the ./prisma folder
sslidentityNoPath to the PKCS12 certificate
sslpasswordNoPassword that was used to secure the PKCS12 file
sslacceptNoaccept_invalid_certsConfigures whether to check for missing values in the certificate. Possible values: accept_invalid_certs, strict
hostNoPoints to a directory that contains a socket to be used for the connection
socket_timeoutNoMaximum number of seconds to wait until a single query terminates
pgbouncerNofalseConfigure the Engine to enable PgBouncer compatibility mode
statement_cache_sizeNo500Since 2.1.0: Specifies the number of prepared statements cached per connection
application_nameNoSince 3.3.0: Specifies a value for the application_name configuration parameter
channel_bindingNopreferSince 4.8.0: Specifies a value for the channel_binding configuration parameter
optionsNoSince 3.8.0: Specifies command line options to send to the server at connection start

As an example, if you want to connect to a schema called myschema, set the connection pool size to 5 and configure a timeout for queries of 3 seconds. You can use the following arguments:

postgresql://USER:PASSWORD@HOST:PORT/DATABASE?schema=myschema&connection_limit=5&socket_timeout=3

Configuring an SSL connection

You can add various parameters to the connection URL if your database server uses SSL. Here's an overview of the possible parameters:

  • sslmode=(disable|prefer|require):
    • prefer (default): Prefer TLS if possible, accept plain text connections.
    • disable: Do not use TLS.
    • require: Require TLS or fail if not possible.
  • sslcert=<PATH>: Path to the server certificate. This is the root certificate used by the database server to sign the client certificate. You need to provide this if the certificate doesn't exist in the trusted certificate store of your system. For Google Cloud this likely is server-ca.pem. Certificate paths are resolved relative to the ./prisma folder
  • sslidentity=<PATH>: Path to the PKCS12 certificate database created from client cert and key. This is the SSL identity file in PKCS12 format which you will generate using the client key and client certificate. It combines these two files in a single file and secures them via a password (see next parameter). You can create this file using your client key and client certificate by using the following command (using openssl):
    openssl pkcs12 -export -out client-identity.p12 -inkey client-key.pem -in client-cert.pem
  • sslpassword=<PASSWORD>: Password that was used to secure the PKCS12 file. The openssl command listed in the previous step will ask for a password while creating the PKCS12 file, you will need to provide that same exact password here.
  • sslaccept=(strict|accept_invalid_certs):
    • strict: Any missing value in the certificate will lead to an error. For Google Cloud, especially if the database doesn't have a domain name, the certificate might miss the domain/IP address, causing an error when connecting.
    • accept_invalid_certs (default): Bypass this check. Be aware of the security consequences of this setting.

Your database connection URL will look similar to this:

postgresql://USER:PASSWORD@HOST:PORT/DATABASE?sslidentity=client-identity.p12&sslpassword=mypassword&sslcert=rootca.cert

Connecting via sockets

To connect to your PostgreSQL database via sockets, you must add a host field as a query parameter to the connection URL (instead of setting it as the host part of the URI). The value of this parameter then must point to the directory that contains the socket, e.g.: postgresql://USER:PASSWORD@localhost/database?host=/var/run/postgresql/

Note that localhost is required, the value itself is ignored and can be anything.

Note: You can find additional context in this .

Type mapping between PostgreSQL and Prisma schema

These two tables show the type mapping between PostgreSQL and Prisma schema. First how Prisma ORM scalar types are translated into PostgreSQL database column types, and then how PostgreSQL database column types relate to Prisma ORM scalar and native types.

Alternatively, see Prisma schema reference for type mappings organized by Prisma type.

Mapping between Prisma ORM scalar types and PostgreSQL database column types

The PostgreSQL connector maps the scalar types from the Prisma ORM data model as follows to database column types:

Prisma ORMPostgreSQL
Stringtext
Booleanboolean
Intinteger
BigIntbigint
Floatdouble precision
Decimaldecimal(65,30)
DateTimetimestamp(3)
Jsonjsonb
Bytesbytea

Mapping between PostgreSQL database column types to Prisma ORM scalar and native types

PostgreSQL (Type | Aliases)SupportedPrisma ORMNative database type attributeNotes
bigint | int8✔️BigInt@db.BigInt**Default mapping for BigInt - no type attribute added to schema.
boolean | bool✔️Bool@db.Boolean**Default mapping for Bool - no type attribute added to schema.
timestamp with time zone | timestamptz✔️DateTime@db.Timestamptz(x)
time without time zone | time✔️DateTime@db.Time(x)
time with time zone | timetz✔️DateTime@db.Timetz(x)
numeric(p,s) | decimal(p,s)✔️Decimal@db.Decimal(x, y)
real | float, float4✔️Float@db.Real
double precision | float8✔️Float@db.DoublePrecision**Default mapping for Float - no type attribute added to schema.
smallint | int2✔️Int@db.SmallInt
integer | int, int4✔️Int@db.Int**Default mapping for Int - no type attribute added to schema.
smallserial | serial2✔️Int@db.SmallInt @default(autoincrement())
serial | serial4✔️Int@db.Int @default(autoincrement())
bigserial | serial8✔️Int@db.BigInt @default(autoincrement()
character(n) | char(n)✔️String@db.Char(x)
character varying(n) | varchar(n)✔️String@db.VarChar(x)
money✔️Decimal@db.Money
text✔️String@db.Text**Default mapping for String - no type attribute added to schema.
timestamp✔️DateTime@db.TimeStamp**Default mapping for DateTime - no type attribute added to schema.
date✔️DateTime@db.Date
enum✔️EnumN/A
inet✔️String@db.Inet
bit(n)✔️String@Bit(x)
bit varying(n)✔️String@VarBit
oid✔️Int@db.Oid
uuid✔️String@db.Uuid
json✔️Json@db.Json
jsonb✔️Json@db.JsonB**Default mapping for Json - no type attribute added to schema.
bytea✔️Bytes@db.ByteA**Default mapping for Bytes - no type attribute added to schema.
xml✔️String@db.Xml
Array types✔️[]
citext✔️*String@db.Citext* Only available if Citext extension is enabled.
intervalNot yetUnsupported
cidrNot yetUnsupported
macaddrNot yetUnsupported
tsvectorNot yetUnsupported
tsqueryNot yetUnsupported
int4rangeNot yetUnsupported
int8rangeNot yetUnsupported
numrangeNot yetUnsupported
tsrangeNot yetUnsupported
tstzrangeNot yetUnsupported
daterangeNot yetUnsupported
pointNot yetUnsupported
lineNot yetUnsupported
lsegNot yetUnsupported
boxNot yetUnsupported
pathNot yetUnsupported
polygonNot yetUnsupported
circleNot yetUnsupported
Composite typesNot yetn/a
Domain typesNot yetn/a

Introspection adds native database types that are not yet supported as Unsupported fields:

schema.prisma
1model Device {
2 id Int @id @default(autoincrement())
3 name String
4 data Unsupported("circle")
5}

Prepared statement caching

A is a feature that can be used to optimize performance. A prepared statement is parsed, compiled, and optimized only once and then can be executed directly multiple times without the overhead of parsing the query again.

By caching prepared statements, Prisma Client's query engine does not repeatedly compile the same query which reduces database CPU usage and query latency.

For example, here is the generated SQL for two different queries made by Prisma Client:

SELECT * FROM user WHERE name = "John";
SELECT * FROM user WHERE name = "Brenda";

The two queries after parameterization will be the same, and the second query can skip the preparing step, saving database CPU and one extra roundtrip to the database. Query after parameterization:

SELECT * FROM user WHERE name = $1

Every database connection maintained by Prisma Client has a separate cache for storing prepared statements. The size of this cache can be tweaked with the statement_cache_size parameter in the connection string. By default, Prisma Client caches 500 statements per connection.

Due to the nature of pgBouncer, if the pgbouncer parameter is set to true, the prepared statement cache is automatically disabled for that connection.