Adapters

Adapters define database connections. Each adapter specifies a database type, connection string, and optional configuration.

Defining adapters

YAML
Dsl

1
adapters:
2
  production_db:
3
    connector: postgres
4
    connection_string: "postgresql://user:pass@host:5432/dbname"
5
    options:
6
      max_connections: "10"
7
      ssl_mode: "require"

adapter production_db {
  connector: postgres
  connection_string: "postgresql://user:pass@host:5432/dbname"
  options: {
    max_connections: "10"
    ssl_mode: "require"
  }
}

Adapter properties

Property	Required	Description
`connector`	Yes	Database type: `postgres`, `mysql`, or `redis`
`connection_string`	Yes	Database connection URL
`options`	No	Connector-specific configuration

Supported connectors

PostgreSQL

1
adapters:
2
  my_postgres:
3
    connector: postgres
4
    connection_string: 'postgresql://user:password@host:5432/database'
5
    options:
6
      max_connections: 10
7
      ssl_mode: 'require' # disable, allow, prefer, require, verify-ca, verify-full
8
      connect_timeout: 10 # seconds

Connection String Format:

1
postgresql://[user]:[password]@[host]:[port]/[database]?[params]

MySQL

1
adapters:
2
  my_mysql:
3
    connector: mysql
4
    connection_string: 'user:password@tcp(host:3306)/database'
5
    options:
6
      max_connections: 10
7
      charset: 'utf8mb4'

Connection String Format:

1
[user]:[password]@tcp([host]:[port])/[database]?[params]

Redis

1
adapters:
2
  my_redis:
3
    connector: redis
4
    connection_string: 'redis://[:password@]host:6379/db'
5
    options:
6
      pool_size: 10

Connection String Format:

1
redis://[:password@]host:port/db

Multiple adapters

You can define multiple adapters for different databases or purposes:

1
adapters:
2
  # Primary database for user data
3
  users_db:
4
    connector: postgres
5
    connection_string: 'postgresql://user:pass@users-db:5432/users'
6

7
  # Analytics database (read replica)
8
  analytics_db:
9
    connector: postgres
10
    connection_string: 'postgresql://readonly:pass@analytics-db:5432/analytics'
11

12
  # Redis for caching
13
  cache:
14
    connector: redis
15
    connection_string: 'redis://cache:6379/0'

Queries reference adapters by name:

1
queries:
2
  get-user:
3
    use: users_db # Uses the users_db adapter
4
    statement: 'SELECT * FROM users WHERE id = {{ inputs.id }}'
5
    # ...
6

7
  get-analytics:
8
    use: analytics_db # Uses the analytics_db adapter
9
    statement: 'SELECT * FROM events WHERE date = {{ inputs.date }}'
10
    # ...

Environment variables

Reference environment variables in connection strings:

1
adapters:
2
  production_db:
3
    connector: postgres
4
    connection_string: '{{ env.DATABASE_URL }}'

Or construct from multiple variables:

1
adapters:
2
  production_db:
3
    connector: postgres
4
    connection_string: 'postgresql://{{ env.DB_USER }}:{{ env.DB_PASS }}@{{ env.DB_HOST }}:5432/{{ env.DB_NAME }}'

Naming conventions

Adapter names must follow these rules:

Use lower-kebab-case or lower_snake_case
Start with a letter
Contain only letters, numbers, hyphens, and underscores

Valid names: main_db, users-db, analytics_replica

Invalid names: MainDB, 123db, my db

Connection security

See the Security section for best practices on:

Protecting connection strings
Using SSL/TLS connections
Network security considerations