45 lines
1.2 KiB
Markdown
45 lines
1.2 KiB
Markdown
# Data Layers
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Data layers determine how resources are stored and retrieved. Examples of data layers:
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- **Postgres**: For storing resources in PostgreSQL (via `AshPostgres`)
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- **ETS**: For in-memory storage (`Ash.DataLayer.Ets`)
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- **Mnesia**: For distributed storage (`Ash.DataLayer.Mnesia`)
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- **Embedded**: For resources embedded in other resources (`data_layer: :embedded`) (typically JSON under the hood)
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- **Ash.DataLayer.Simple**: For resources that aren't persisted at all. Leave off the data layer, as this is the default.
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Specify a data layer when defining a resource:
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```elixir
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defmodule MyApp.Post do
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use Ash.Resource,
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domain: MyApp.Blog,
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data_layer: AshPostgres.DataLayer
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postgres do
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table "posts"
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repo MyApp.Repo
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end
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# ... attributes, relationships, etc.
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end
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```
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For embedded resources:
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```elixir
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defmodule MyApp.Address do
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use Ash.Resource,
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data_layer: :embedded
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attributes do
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attribute :street, :string
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attribute :city, :string
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attribute :state, :string
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attribute :zip, :string
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end
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end
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```
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Each data layer has its own configuration options and capabilities. Refer to the rules & documentation of the specific data layer package for more details.
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