void StartNewPureValueFile()
{
_pureValueFile = _fileCollection.AddFile("hpv");
_pureValueFileWriter = _pureValueFile.GetAppenderWriter();
var fileInfo = new FilePureValuesWithId(_subDBId, _fileCollection.NextGeneration(), _fileCollection.Guid);
fileInfo.WriteHeader(_pureValueFileWriter);
_fileCollection.SetInfo(_pureValueFile.Index, fileInfo);
}
