mongodb/mongoid · error · Mongoid::Errors::InvalidElemMatchOperator

Invalid $elemMatch operator '%{operator}'.

Error message

Invalid $elemMatch operator '%{operator}'.

What it means

Error "Invalid $elemMatch operator '%{operator}'." thrown in mongodb/mongoid.

Source

Thrown at lib/mongoid/matcher/elem_match_expression.rb:24

    # also have a regular expression predicate.
    #
    # @api private
    module ElemMatchExpression
      # Returns whether a document satisfies an $elemMatch expression.
      #
      # @param [ Mongoid::Document ] document The document.
      # @param [ Hash ] expr The $elemMatch condition predicate.
      #
      # @return [ true | false ] Whether the document matches.
      #
      # @api private
      module_function def matches?(document, expr)
        Expression.matches?(document, expr)
      rescue Mongoid::Errors::InvalidExpressionOperator
        begin
          FieldExpression.matches?(true, document, expr)
        rescue Mongoid::Errors::InvalidFieldOperator => exc
          raise Mongoid::Errors::InvalidElemMatchOperator.new(exc.operator)
        end
      end
    end
  end
end

View on GitHub (pinned to 0da0e23d71)

When it happens

Trigger: Thrown at lib/mongoid/matcher/elem_match_expression.rb:24 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of mongodb/mongoid@0da0e23d71 (2026-08-23). Data as JSON: /api/errors/b6d8151e9a6c8fc2. Report an issue: GitHub.