void CalcPrefixKeyStart()
{
if (_prefixKeyStart >= 0)
{
return;
}
if (_cursor2 == null)
{
_cursor2 = BTreeRoot.CreateCursor();
}
if (_cursor2.FindFirst(_prefix))
{
_prefixKeyStart = _cursor2.CalcIndex();
}
else
{
_prefixKeyStart = -1;
}
}
public void EraseRange(long firstKeyIndex, long lastKeyIndex)
{
if (firstKeyIndex < 0)
{
firstKeyIndex = 0;
}
if (lastKeyIndex >= GetKeyValueCount())
{
lastKeyIndex = _prefixKeyCount - 1;
}
if (lastKeyIndex < firstKeyIndex)
{
return;
}
MakeWritable();
firstKeyIndex += _prefixKeyStart;
lastKeyIndex += _prefixKeyStart;
_cursor.SeekIndex(firstKeyIndex);
if (lastKeyIndex != firstKeyIndex)
{
if (_cursor2 == null)
{
_cursor2 = BTreeRoot.CreateCursor();
}
_cursor2.SeekIndex(lastKeyIndex);
var firstKey = GetCurrentKeyFromStack();
var secondKey = ByteBuffer.NewAsync(new byte[_cursor2.GetKeyLength()]);
_cursor2.FillByKey(secondKey.AsSyncSpan());
_keyValueDB.WriteEraseRangeCommand(firstKey, secondKey);
_cursor.EraseTo(_cursor2);
}
else
{
_keyValueDB.WriteEraseOneCommand(GetCurrentKeyFromStack());
_cursor.Erase();
}
InvalidateCurrentKey();
_prefixKeyCount -= lastKeyIndex - firstKeyIndex + 1;
}
public long GetKeyValueCount()
{
if (_prefixKeyCount >= 0)
{
return(_prefixKeyCount);
}
if (_prefix.Length == 0)
{
_prefixKeyCount = BTreeRoot.GetCount();
return(_prefixKeyCount);
}
CalcPrefixKeyStart();
if (_prefixKeyStart < 0)
{
_prefixKeyCount = 0;
return(0);
}
if (_cursor2 == null)
{
_cursor2 = BTreeRoot.CreateCursor();
}
_prefixKeyCount = _cursor2.FindLastWithPrefix(_prefix) - _prefixKeyStart + 1;
return(_prefixKeyCount);
}