Method getPrefix

fdbserver/KeyValueStoreSQLite.actor.cpp:1143–1167

		return Optional<Value>();
	}
	Optional<Value> getPrefix(KeyRef key, int maxLength) {
		if (db.fragment_values) {
			int r = moveTo(key);
			if (r < 0)
				moveNext();
			Arena m;
			DefragmentingReader i(*this, m, getEncodedKVFragmentSize(key.size(), maxLength));
			if (i.peek() == key) {
				Optional<KeyValueRef> kv = i.getNext();
				kvBytesRead += key.size() + kv.get().value.size();
				return Value(kv.get().value, m);
			}
		} else if (!moveTo(key)) {
			if (maxLength == 0) {
				return Value();
			}
			Value result;
			int maxEncodedSize = getEncodedSize(key.size(), maxLength);
			KeyValueRef kv = decodeKVPrefix(getEncodedRowPrefix(result.arena(), maxEncodedSize), maxLength);
			((ValueRef&)result) = kv.value;
			kvBytesRead += key.size() + result.size();
			return result;
		}
		return Optional<Value>();
	}
	RangeResult getRange(KeyRangeRef keys, int rowLimit, int byteLimit) {
		RangeResult result;
		int accumulatedBytes = 0;