Database Setup

Cal.com uses PostgreSQL as its primary database. This guide covers database setup, migrations, connection pooling, and optimization.

Requirements

PostgreSQL: Version 13 or higher
Storage: Minimum 20GB, recommended 100GB+ for production
Memory: Minimum 2GB RAM allocated to PostgreSQL
Connection Limit: Adjust based on your deployment scale

Local PostgreSQL Installation

Ubuntu/Debian

# Install PostgreSQL
sudo apt-get update
sudo apt-get install postgresql postgresql-contrib

# Start PostgreSQL service
sudo systemctl start postgresql
sudo systemctl enable postgresql

macOS

# Using Homebrew
brew install postgresql@15
brew services start postgresql@15

Windows

Download from postgresql.org and follow the installer.

Create Database

# Connect to PostgreSQL
sudo -u postgres psql

# Create database and user
CREATE DATABASE calendso;
CREATE USER calcom_user WITH ENCRYPTED PASSWORD 'your_secure_password';
GRANT ALL PRIVILEGES ON DATABASE calendso TO calcom_user;

# Grant schema permissions (PostgreSQL 15+)
\c calendso
GRANT ALL ON SCHEMA public TO calcom_user;
\q

Connection String Format

PostgreSQL connection strings follow this format:

postgresql://[user]:[password]@[host]:[port]/[database]?[parameters]

Examples:

# Local database
DATABASE_URL="postgresql://calcom_user:password@localhost:5432/calendso"

# Remote with SSL
DATABASE_URL="postgresql://user:pass@db.example.com:5432/calendso?sslmode=require"

# With connection pooling
DATABASE_URL="postgresql://user:pass@pooler.example.com:6543/calendso?pgbouncer=true"

# Self-signed SSL (Heroku, etc.)
DATABASE_URL="postgresql://user:pass@host:5432/db?sslmode=no-verify"

Environment Configuration

Add to your .env file:

# Primary database connection
DATABASE_URL="postgresql://calcom_user:password@localhost:5432/calendso"

# Direct connection for migrations (same as DATABASE_URL if not using pooling)
DATABASE_DIRECT_URL="postgresql://calcom_user:password@localhost:5432/calendso"

# Optional: Separate analytics database
INSIGHTS_DATABASE_URL="postgresql://user:pass@host:5432/calendso_insights"

# Optional: SAML database (Enterprise)
SAML_DATABASE_URL="postgresql://user:pass@host:5432/calendso_saml"

Migrations

Cal.com uses Prisma for database schema management and migrations.

Initial Setup

For a new database, run migrations to create all tables:

# Development (includes seeding)
yarn workspace @calcom/prisma db-migrate

# Production (no seeding)
yarn workspace @calcom/prisma db-deploy

Migration Commands

# Apply pending migrations and generate Prisma Client
yarn workspace @calcom/prisma db-migrate

# Create a new migration
yarn workspace @calcom/prisma db-migrate-create "migration_name"

# Reset database (⚠️ deletes all data)
yarn workspace @calcom/prisma db-reset

Migration Best Practices

Always backup your database before running migrations in production
Test migrations in staging environment first
Use db-deploy (not db-migrate) in production
Never run db-reset in production (destroys all data)

The Docker start.sh script automatically runs migrations on container startup:

npx prisma migrate deploy --schema /calcom/packages/prisma/schema.prisma

Schema Location

The Prisma schema is located at:

packages/prisma/schema.prisma

Migration Directory

Migration files are stored in:

packages/prisma/migrations/

Connection Pooling

Why Use Connection Pooling?

Connection poolers like PgBouncer help:

Reduce database connection overhead
Handle high-concurrency workloads
Manage connection limits efficiently
Improve application performance

PgBouncer Setup

Using Docker

services:
  pgbouncer:
    image: pgbouncer/pgbouncer:latest
    environment:
      - DATABASES_HOST=database
      - DATABASES_PORT=5432
      - DATABASES_USER=calcom_user
      - DATABASES_PASSWORD=password
      - DATABASES_DBNAME=calendso
      - PGBOUNCER_POOL_MODE=transaction
      - PGBOUNCER_MAX_CLIENT_CONN=1000
      - PGBOUNCER_DEFAULT_POOL_SIZE=25
    ports:
      - "6432:6432"
    depends_on:
      - database

Configuration

Update your .env to use PgBouncer:

# Application connects through PgBouncer
DATABASE_URL="postgresql://calcom_user:password@pgbouncer:6432/calendso?pgbouncer=true"

# Migrations bypass PgBouncer (direct connection required)
DATABASE_DIRECT_URL="postgresql://calcom_user:password@database:5432/calendso"

DATABASE_DIRECT_URL must point to the actual database (not pooler) for migrations to work correctly.

Managed Pooling Services

Many providers offer built-in connection pooling:

Supabase

# Pooled connection (port 6543)
DATABASE_URL="postgresql://postgres:pass@db.xxx.supabase.co:6543/postgres"

# Direct connection (port 5432)
DATABASE_DIRECT_URL="postgresql://postgres:pass@db.xxx.supabase.co:5432/postgres"

Railway

Railway automatically provides both pooled and direct connections.

Neon

# Pooled endpoint
DATABASE_URL="postgresql://user:pass@ep-xxx.pooler.neon.tech/db?sslmode=require"

# Direct endpoint
DATABASE_DIRECT_URL="postgresql://user:pass@ep-xxx.neon.tech/db?sslmode=require"

Managed Database Providers

Railway

Create a new PostgreSQL database in Railway
Copy the connection string from Railway dashboard
Add to .env:

DATABASE_URL="postgresql://postgres:password@containers-xx.railway.app:5432/railway"
DATABASE_DIRECT_URL="postgresql://postgres:password@containers-xx.railway.app:5432/railway"

Railway PostgreSQL Guide

Render

Create a new PostgreSQL database in Render
Get external connection string
Configure:

DATABASE_URL="postgresql://user:pass@dpg-xxx.render.com/db_xxx"
DATABASE_DIRECT_URL="postgresql://user:pass@dpg-xxx.render.com/db_xxx"

Render PostgreSQL Docs

Supabase

Create a new Supabase project
Get connection strings from Settings > Database
Use pooled connection for app, direct for migrations:

DATABASE_URL="postgresql://postgres:pass@db.xxx.supabase.co:6543/postgres?pgbouncer=true"
DATABASE_DIRECT_URL="postgresql://postgres:pass@db.xxx.supabase.co:5432/postgres"

Neon

Create a Neon project
Get pooled and direct connection strings
Configure:

DATABASE_URL="postgresql://user:pass@ep-xxx.pooler.neon.tech/neondb"
DATABASE_DIRECT_URL="postgresql://user:pass@ep-xxx.neon.tech/neondb"

Neon Quickstart

Amazon RDS

Create RDS PostgreSQL instance
Configure security groups for access
Get endpoint from RDS console:

DATABASE_URL="postgresql://postgres:pass@mydb.xxx.rds.amazonaws.com:5432/calendso"
DATABASE_DIRECT_URL="postgresql://postgres:pass@mydb.xxx.rds.amazonaws.com:5432/calendso"

SSL Configuration

Requiring SSL

DATABASE_URL="postgresql://user:pass@host:5432/db?sslmode=require"

Self-Signed Certificates

For platforms like Heroku with self-signed certs:

PGSSLMODE="no-verify"
DATABASE_URL="postgresql://user:pass@host:5432/db"

Only use sslmode=no-verify when you trust the network and database provider.

SSL Modes

disable: No SSL
prefer: Try SSL, fallback to non-SSL
require: Require SSL, but don’t verify certificates
verify-ca: Require SSL and verify certificate
verify-full: Require SSL, verify certificate and hostname

Database Optimization

Indexes

Cal.com’s schema includes optimized indexes. Monitor slow queries:

-- Enable query logging
ALTER DATABASE calendso SET log_min_duration_statement = 1000;

-- Find slow queries
SELECT query, calls, total_time, mean_time
FROM pg_stat_statements
ORDER BY mean_time DESC
LIMIT 10;

Connection Limits

Adjust PostgreSQL connection limits in postgresql.conf:

max_connections = 100
shared_buffers = 256MB
effective_cache_size = 1GB
work_mem = 4MB
maintenance_work_mem = 64MB

Vacuum and Analyze

Enable auto-vacuum for maintenance:

-- Check auto-vacuum settings
SHOW autovacuum;

-- Manual vacuum analyze
VACUUM ANALYZE;

Backup Strategies

pg_dump Backup

# Backup database
pg_dump -h localhost -U calcom_user -d calendso -F c -f backup_$(date +%Y%m%d).dump

# Restore database
pg_restore -h localhost -U calcom_user -d calendso -c backup_20260304.dump

Continuous Archiving (WAL)

For point-in-time recovery, enable WAL archiving:

wal_level = replica
archive_mode = on
archive_command = 'cp %p /path/to/archive/%f'

Managed Backups

Most managed providers offer automatic backups:

Supabase: Daily backups with point-in-time recovery
Railway: Automatic daily backups
Render: Daily backups included
RDS: Automated backups with configurable retention

Database Management Tools

Prisma Studio

Visual database browser included with Cal.com:

# Start Prisma Studio
yarn db-studio

# Access at http://localhost:5555

Prisma Studio is available in the Docker Compose setup at port 5555. Remove this service in production.

pgAdmin

Full-featured PostgreSQL management:

docker run -p 5050:80 \
  -e PGADMIN_DEFAULT_EMAIL=admin@example.com \
  -e PGADMIN_DEFAULT_PASSWORD=admin \
  dpage/pgadmin4

psql CLI

Connect directly to your database:

# Local connection
psql -U calcom_user -d calendso

# Remote connection
psql "postgresql://user:pass@host:5432/db?sslmode=require"

# Common commands
\dt          # List tables
\d+ table    # Describe table
\l           # List databases
\conninfo    # Connection info

Docker Compose Database

The default docker-compose.yml includes PostgreSQL:

services:
  database:
    container_name: database
    image: postgres
    restart: always
    volumes:
      - database-data:/var/lib/postgresql
    environment:
      - POSTGRES_USER=unicorn_user
      - POSTGRES_PASSWORD=magical_password
      - POSTGRES_DB=calendso
    networks:
      - stack

volumes:
  database-data:

Change default credentials in production:

environment:
  - POSTGRES_USER=calcom_prod
  - POSTGRES_PASSWORD=${DB_PASSWORD}  # Use env var
  - POSTGRES_DB=calendso

Separate Databases

Insights Database

For analytics workload isolation:

INSIGHTS_DATABASE_URL="postgresql://user:pass@analytics-db:5432/insights"

SAML Database (Enterprise)

For SAML SSO data:

SAML_DATABASE_URL="postgresql://user:pass@host:5432/calendso_saml"

Create the SAML database:

CREATE DATABASE calendso_saml;
GRANT ALL PRIVILEGES ON DATABASE calendso_saml TO calcom_user;

Troubleshooting

Connection Refused

Error: connect ECONNREFUSED 127.0.0.1:5432

Solutions:

Verify PostgreSQL is running: sudo systemctl status postgresql
Check port: sudo netstat -plnt | grep 5432
Review pg_hba.conf for connection permissions

Too Many Connections

Error: sorry, too many clients already

Solutions:

Implement connection pooling (PgBouncer)
Increase max_connections in PostgreSQL
Check for connection leaks in application

Migration Failures

Error: Migration failed to apply

Solutions:

Use DATABASE_DIRECT_URL (not pooled connection)
Check database permissions
Review migration logs: yarn workspace @calcom/prisma db-migrate status
Manually resolve conflicts in failed migrations

Permission Denied

Error: permission denied for schema public

Solution (PostgreSQL 15+):

\c calendso
GRANT ALL ON SCHEMA public TO calcom_user;
GRANT ALL ON ALL TABLES IN SCHEMA public TO calcom_user;
GRANT ALL ON ALL SEQUENCES IN SCHEMA public TO calcom_user;

Authentication Failed

Error: password authentication failed for user "calcom_user"

Solutions:

Verify credentials in DATABASE_URL
URL-encode special characters in password
Check pg_hba.conf authentication method (md5/scram-sha-256)

Performance Monitoring

Query Statistics

Enable pg_stat_statements extension:

CREATE EXTENSION IF NOT EXISTS pg_stat_statements;

-- View slow queries
SELECT query, calls, total_time, mean_time, max_time
FROM pg_stat_statements
ORDER BY total_time DESC
LIMIT 20;

Connection Monitoring

-- Current connections
SELECT count(*) FROM pg_stat_activity;

-- Connections by state
SELECT state, count(*) 
FROM pg_stat_activity 
GROUP BY state;

-- Long-running queries
SELECT pid, now() - query_start AS duration, query
FROM pg_stat_activity
WHERE state = 'active'
ORDER BY duration DESC;

Production Checklist

Next Steps

Review Configuration for database-related environment variables
See Docker Setup for containerized database deployment
Check Deployment for platform-specific database configurations

Get Started

Core Features

Integrations

Embedding

Self-Hosting

Enterprise

Documentation Index

​Requirements

​Database Setup

​Local PostgreSQL Installation

​Ubuntu/Debian

​macOS

​Windows

​Create Database

​Connection String Format

​Environment Configuration

​Migrations

​Initial Setup

​Migration Commands

​Migration Best Practices

​Schema Location

​Migration Directory

​Connection Pooling

​Why Use Connection Pooling?

​PgBouncer Setup

​Using Docker

​Configuration

​Managed Pooling Services

​Supabase

​Railway

​Neon

​Managed Database Providers

​Railway

​Render

​Supabase

​Neon

​Amazon RDS

​SSL Configuration

​Requiring SSL

​Self-Signed Certificates

​SSL Modes

​Database Optimization

​Indexes

​Connection Limits

​Vacuum and Analyze

​Backup Strategies

​pg_dump Backup

​Continuous Archiving (WAL)

​Managed Backups

​Database Management Tools

​Prisma Studio

​pgAdmin

​psql CLI

​Docker Compose Database

​Separate Databases

​Insights Database

​SAML Database (Enterprise)

​Troubleshooting

​Connection Refused

​Too Many Connections

​Migration Failures

​Permission Denied

​Authentication Failed

​Performance Monitoring

​Query Statistics

​Connection Monitoring

​Production Checklist

​Next Steps

Build docs developers (and LLMs) love

Requirements

Database Setup

Local PostgreSQL Installation

Ubuntu/Debian

macOS

Windows

Create Database

Connection String Format

Environment Configuration

Migrations

Initial Setup

Migration Commands

Migration Best Practices

Schema Location

Migration Directory

Connection Pooling

Why Use Connection Pooling?

PgBouncer Setup

Using Docker

Configuration

Managed Pooling Services

Supabase

Railway

Neon

Managed Database Providers

Railway

Render

Supabase

Neon

Amazon RDS

SSL Configuration

Requiring SSL

Self-Signed Certificates

SSL Modes

Database Optimization

Indexes

Connection Limits

Vacuum and Analyze

Backup Strategies

pg_dump Backup

Continuous Archiving (WAL)

Managed Backups

Database Management Tools

Prisma Studio

pgAdmin

psql CLI

Docker Compose Database

Separate Databases

Insights Database

SAML Database (Enterprise)

Troubleshooting

Connection Refused

Too Many Connections

Migration Failures

Permission Denied

Authentication Failed

Performance Monitoring

Query Statistics

Connection Monitoring

Production Checklist

Next Steps