This function is EXPERIMENTAL. The behaviour of this function, the name of this function, and anything else documented about this function may change in a future release of PHP without notice. Be warned and use this function at your own risk.
dbplus_getunique() will obtain a number guaranteed to be unique for the given relation and will pass it back in the variable given as uniqueid.
The function will return zero (aka. DBPLUS_ERR_NOERR) on success or a db++ error code on failure. See dbplus_errcode() or the introduction to this chapter for more information on db++ error codes.