Database Configuration

PormG uses a flexible configuration system designed for Julia's asynchronous environment. Whether you are building a simple script or a complex multi-tenant server, PormG provides the tools to manage your database connections reliably.

Core Concepts

1. Configuration Folders

In PormG, a Configuration Folder (like db/ or db_sch/) is the unit of connection management. Each folder contains a connection.yml file that defines how to connect to the database.

• Default Folder: If you don't specify a path, PormG often looks for db/.
• Multiple Databases: You can have multiple folders (e.g., db_primary, db_analytics) to manage different connections in the same app.

2. Environments (app_env)

PormG supports multiple environments within the same connection.yml. Common values are dev, test, and prod. You can specify the environment globally via ENV["PORMG_ENV"] or explicitly in the load call.

3. Supported Adapters

• PostgreSQL: Primary adapter using LibPQ.jl. Supports high-performance async operations.
• SQLite: Fully supported via SQLite.jl. PormG uses a unique Contextual Buckets Strategy to enable complex joins and CTEs that are normally difficult in SQLite.

Philosophy

The server application should keep:

• Mapping AppConfig to a set of database folders.
• Deciding whether a failed database should fail startup.
• Formatting HTTP health responses.

PormG should own:

• Loading and reloading database folders.
• Environment-aware configuration selection.
• Mapping folder paths to connection keys.
• Answering loaded-state and connectivity questions.