Migrations create and modify the database tables TelemetryUI needs to function.

usage

Usage

To use migrations in your application you'll need to generate an Ecto.Migration that wraps calls to TelemetryUI.Backend.EctoPostgres.Migrations:

mix ecto.gen.migration add_telemetry_ui

Open the generated migration in your editor and call the up and down functions on TelemetryUI.Backend.EctoPostgres.Migrations:

defmodule MyApp.Repo.Migrations.AddTelemetryUI do
  use Ecto.Migration

  def up, do: TelemetryUI.Backend.EctoPostgres.Migrations.up()

  def down, do: TelemetryUI.Backend.EctoPostgres.Migrations.down()
end

This will run all of TelemetryUI's versioned migrations for your database.

Now, run the migration to create the table:

mix ecto.migrate

Migrations between versions are idempotent. As new versions are released, you may need to run additional migrations. To do this, generate a new migration:

mix ecto.gen.migration upgrade_telemetry_ui_to_v11

Open the generated migration in your editor and call the up and down functions on TelemetryUI.Backend.EctoPostgres.Migrations, passing a version number:

defmodule MyApp.Repo.Migrations.UpgradeTelemetryUIToV11 do
  use Ecto.Migration

  def up, do: TelemetryUI.Backend.EctoPostgres.Migrations.up(version: 11)

  def down, do: TelemetryUI.Backend.EctoPostgres.Migrations.down(version: 11)
end

isolation-with-prefixes

Isolation with Prefixes

TelemetryUI supports namespacing through PostgreSQL schemas, also called "prefixes" in Ecto. With prefixes your events table can reside outside of your primary schema (usually public) and you can have multiple separate job tables.

To use a prefix you first have to specify it within your migration:

defmodule MyApp.Repo.Migrations.AddPrefixedTelemetryUIJobsTable do
  use Ecto.Migration

  def up, do: TelemetryUI.Backend.EctoPostgres.Migrations.up(prefix: "private")

  def down, do: TelemetryUI.Backend.EctoPostgres.Migrations.down(prefix: "private")
end

The migration will create the "private" schema and all tables, functions and triggers within that schema. With the database migrated you'll then specify the prefix in your configuration:

config :my_app, TelemetryUI,
  prefix: "private",
  ...

In some cases, for example if your "private" schema already exists and your database user in production doesn't have permissions to create a new schema, trying to create the schema from the migration will result in an error. In such situations, it may be useful to inhibit the creation of the "private" schema:

defmodule MyApp.Repo.Migrations.AddPrefixedTelemetryUIJobsTable do
  use Ecto.Migration

  def up, do: TelemetryUI.Backend.EctoPostgres.Migrations.up(prefix: "private", create_schema: false)

  def down, do: TelemetryUI.Backend.EctoPostgres.Migrations.down(prefix: "private")
end