gitlab-org--gitlab-foss/app/models/concerns/from_except.rb

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# frozen_string_literal: true
module FromExcept
extend ActiveSupport::Concern
class_methods do
# Produces a query that uses a FROM to select data using an EXCEPT.
#
# Example:
# groups = Group.from_except([group1.self_and_hierarchy, group2.self_and_hierarchy])
#
# This would produce the following SQL query:
#
# SELECT *
# FROM (
# SELECT "namespaces". *
# ...
#
# EXCEPT
#
# SELECT "namespaces". *
# ...
# ) groups;
#
# members - An Array of ActiveRecord::Relation objects to use in the except.
#
# remove_duplicates - A boolean indicating if duplicate entries should be
# removed. Defaults to true.
#
# alias_as - The alias to use for the sub query. Defaults to the name of the
# table of the current model.
# rubocop: disable Gitlab/Except
extend FromSetOperator
define_set_operator Gitlab::SQL::Except
# rubocop: enable Gitlab/Except
end
end