# `Ash.DataLayer.Mnesia`
[🔗](https://github.com/ash-project/ash/blob/v3.23.1/lib/ash/data_layer/mnesia/mnesia.ex#L5)

An Mnesia backed Ash Datalayer.

In your application initialization, you will need to call `Mnesia.create_schema([node()])`.

Additionally, you will want to create your mnesia tables there.

This data layer is *unoptimized*, fetching all records from a table and filtering them
in memory. For that reason, it is not recommended to use it with large amounts of data. It can be
great for prototyping or light usage, though.

# `bulk_create`

Bulk create records in the database.

This function is used to create multiple records in a single transaction.

If you are NOT setting the `upsert? = true` option, this will be optimized by
creating a single transaction and bulk creating all of the entries. The way
:mnesia.write works, will effectively do an upsert, but you cannot control
which fields are updated and the only identity you are matching on is the
primary key.

If you are using an `upsert?` it will be unoptimized and will load all records
into memory before performing the upsert operation.

# `mnesia`
*macro* 

# `start`

Creates the table for each mnesia resource in a domain

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