def drop_index(namespace, set_name, index_name, options = nil)
      policy = create_policy(options, Policy, default_info_policy)

      str_cmd = "sindex-delete:ns=#{namespace}"
      str_cmd << ";set=#{set_name}" unless set_name.to_s.strip.empty?
      str_cmd << ";indexname=#{index_name}"

      # Send index command to one node. That node will distribute the command to other nodes.
      response = send_info_command(policy, str_cmd).upcase
      return if response == 'OK'

      # Index did not previously exist. Return without error.
      return if response.start_with?('FAIL:201')

      raise Aerospike::Exceptions::Aerospike.new(Aerospike::ResultCode::INDEX_GENERIC, "Drop index failed: #{response}")
    end
def drop_index(namespace, set_name, index_name, options = nil)
      policy = create_policy(options, Policy, default_info_policy)

      str_cmd = "sindex-delete:ns=#{namespace}"
      str_cmd << ";set=#{set_name}" unless set_name.to_s.strip.empty?
      str_cmd << ";indexname=#{index_name}"

      # Send index command to one node. That node will distribute the command to other nodes.
      response = send_info_command(policy, str_cmd).upcase
      return if response == 'OK'

      # Index did not previously exist. Return without error.
      return if response.start_with?('FAIL:201')

      raise Aerospike::Exceptions::Aerospike.new(Aerospike::ResultCode::INDEX_GENERIC, "Drop index failed: #{response}")
    end
Delete secondary index.
  This method is only supported by Aerospike 3 servers.