Beispiel #1
0
// next gives the left boundary of the union of all requests which don't
// affect keys less than the given key.
// TODO(tschottdorf): again, better on BatchRequest itself, but can't pull
// 'keys' into 'proto'.
func next(ba roachpb.BatchRequest, k roachpb.RKey) (roachpb.RKey, error) {
	candidate := roachpb.RKeyMax
	for _, union := range ba.Requests {
		h := union.GetInner().Header()
		addr, err := keys.Addr(h.Key)
		if err != nil {
			return nil, err
		}
		if addr.Less(k) {
			eAddr, err := keys.AddrUpperBound(h.EndKey)
			if err != nil {
				return nil, err
			}
			if k.Less(eAddr) {
				// Starts below k, but continues beyond. Need to stay at k.
				return k, nil
			}
			// Affects only [KeyMin,k).
			continue
		}
		// We want the smallest of the surviving candidates.
		if addr.Less(candidate) {
			candidate = addr
		}
	}
	return candidate, nil
}
Beispiel #2
0
// prev gives the right boundary of the union of all requests which don't
// affect keys larger than the given key.
// TODO(tschottdorf): again, better on BatchRequest itself, but can't pull
// 'keys' into 'roachpb'.
func prev(ba roachpb.BatchRequest, k roachpb.RKey) (roachpb.RKey, error) {
	candidate := roachpb.RKeyMin
	for _, union := range ba.Requests {
		h := union.GetInner().Header()
		addr, err := keys.Addr(h.Key)
		if err != nil {
			return nil, err
		}
		eAddr, err := keys.AddrUpperBound(h.EndKey)
		if err != nil {
			return nil, err
		}
		if len(eAddr) == 0 {
			eAddr = addr.Next()
		}
		if !eAddr.Less(k) {
			if !k.Less(addr) {
				// Range contains k, so won't be able to go lower.
				return k, nil
			}
			// Range is disjoint from [KeyMin,k).
			continue
		}
		// We want the largest surviving candidate.
		if candidate.Less(addr) {
			candidate = addr
		}
	}
	return candidate, nil
}