grape

Gitlab::Database::MigrationHelpers#queue_background_migration_jobs_by_range_at_intervals

Queues background migration jobs for an entire table, batched by ID range.
Each job is scheduled with a `delay_interval` in between.
If you use a small interval, then some jobs may run at the same time.

model_class - The table being iterated over
job_class_name - The background migration job class as a string
delay_interval - The duration between each job's scheduled time (must respond to `to_f`)
batch_size - The maximum number of rows per job

Example:

    class Route < ActiveRecord::Base
      include EachBatch
      self.table_name = 'routes'
    end

    queue_background_migration_jobs_by_range_at_intervals(Route, 'ProcessRoutes', 1.minute)

Where the model_class includes EachBatch, and the background migration exists:

    class Gitlab::BackgroundMigration::ProcessRoutes
      def perform(start_id, end_id)
        # do something
      end
    end

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