The following functions are defined to build name-value records:
hc_nvr_add_value
hc_nvr_add_long
hc_nvr_add_double
hc_nvr_add_string
hc_nvr_add_binary
hc_nvr_add_date
hc_nvr_add_time
hc_nvr_add_timestamp
hc_nvr_add_from_string