25 lines
736 B
Ruby
25 lines
736 B
Ruby
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# frozen_string_literal: true
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# Distinguish between a top level query and a subselect.
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#
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# Retrieve column values when the relation has already been loaded, otherwise reselect the relation.
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# Useful for preload query patterns where the typical Rails #preload does not fit. Such as:
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#
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# projects = Project.where(...)
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# projects.load
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# ...
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# options[members] = ProjectMember.where(...).where(source_id: projects.select(:id))
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module Subquery
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extend ActiveSupport::Concern
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class_methods do
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def subquery(*column_names, max_limit: 5_000)
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if current_scope.loaded? && current_scope.size <= max_limit
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current_scope.pluck(*column_names)
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else
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current_scope.reselect(*column_names)
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end
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end
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end
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end
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