columnId >= recordHeader.getFirstField(),
"first column on page > expected");
}
// these reads are always against the page array
ArrayInputStream lrdi = rawDataIn;
// set read position to data portion of record to check.
int offset = getRecordOffset(slot);
lrdi.setPosition(offset + recordHeader.size());
// skip until you get to the record in question.
for (int i = recordHeader.getFirstField(); i < columnId; i++)
skipField(lrdi);