# `AshScylla.MigrationGenerator`
[🔗](https://github.com/ohhi-vn/ash_scylla/blob/main/lib/ash_scylla/migration_generator.ex#L15)

Generates CQL migration files from Ash resource definitions.

Compares current Ash resource snapshots against the live ScyllaDB schema
and generates CQL statements to bring the schema in sync.

## Usage

    # Generate a migration for all resources
    mix ash_scylla.generate_migrations

    # Generate with a specific name
    mix ash_scylla.generate_migrations add_user_table

    # Dry run (print without creating files)
    mix ash_scylla.generate_migrations --dry-run

    # Check if migrations are needed (exit code 1 if so)
    mix ash_scylla.generate_migrations --check

## Snapshots

Snapshots are stored in `priv/repo_name/resource_snapshots/` as JSON files.
Each snapshot captures the state of a resource's schema at a point in time.
The migration generator compares the current resource definition against the
most recent snapshot to determine what changes need to be made.

# `generate`

Main entry point for migration generation.

Options:
  - `:domains` - list of domains to generate for (defaults to all configured)
  - `:snapshot_path` - custom path for snapshots (default: `priv/repo/resource_snapshots`)
  - `:migration_path` - custom path for migrations (default: `priv/repo/migrations`)
  - `:name` - name for the migration (auto-generated if not provided)
  - `:quiet` - suppress output
  - `:format` - format generated Elixir code (default: true)
  - `:dry_run` - print migrations without creating files
  - `:check` - return exit code 1 if migrations needed
  - `:dev` - create dev migrations (suffixed with `_dev`)
  - `:snapshots_only` - only create snapshots, no migration files

# `take_snapshots`

Takes snapshots of the given resources without generating migrations.
Useful for initial setup.

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*Consult [api-reference.md](api-reference.md) for complete listing*