getEstimatedExtentNid method
Estimated full extent for the live nid — measured value when
available, defaultExtent otherwise. Hot-path equivalent of
getEstimatedExtent that avoids the TKey→nid hash. Caller must
guarantee nid is live and within range.
Implementation
double getEstimatedExtentNid(int nid) {
final ext = _fullExtentByNid[nid];
return ext < 0 ? defaultExtent : ext;
}