DSL extensions for configuring ScyllaDB-specific options on Ash resources.

Usage

defmodule MyApp.MyResource do
  use Ash.Resource,
    data_layer: AshScylla.DataLayer

  ash_scylla do
    table "my_table"
    keyspace "my_keyspace"
    consistency :quorum
    ttl 3600

    # Define secondary indexes for non-primary key columns
    secondary_index :email
    secondary_index [:name, :age]
    secondary_index :status, name: "idx_user_status"
    lwt true  # Enable lightweight transactions for atomic updates
  end

  attributes do
    uuid_primary_key :id
    attribute :name, :string
    attribute :email, :string
    attribute :status, :string
    attribute :age, :integer
  end
end

Options

• :table - The table name in ScyllaDB (overrides default)
• :keyspace - The keyspace to use (overrides repo default)
• :consistency - The consistency level for reads/writes
• :ttl - Default TTL for inserted records (in seconds)
• :lwt - Enable Lightweight Transactions (LWT) for atomic upserts using INSERT ... IF NOT EXISTS (default: false)
• :secondary_index - Define secondary indexes for non-primary key columns
• :materialized_view - Define materialized views with different primary key structure
• :pagination - Pagination mode: :offset (default) or :token for token-based pagination
• :per_action_consistency - Per-action consistency overrides as a keyword list, e.g. [read: :one, create: :quorum]

Features

The data layer supports:

• Upsert (:upsert) - Insert-or-update semantics with optional LWT
• Atomic updates ({:atomic, :update}) - LWT-based conditional updates
• Atomic upserts ({:atomic, :upsert}) - LWT-based insert-or-update
• Bulk update/destroy - update_query and destroy_query for filtered operations
• Distinct - On partition-key columns only
• Aggregates - COUNT via :count aggregate
• Expression calculations - In-memory post-processing
• Boolean filter - With OR-to-IN rewriting