You have the option of reading any track segments and track points that may have been collected during the run. Normally you will do so.
Caution: new track segments read in will replace track segments for the same area that are already in the database. If the data also contains track points, they are simply added to the database. If two runs covering the same territory are both read into the same database, and both contain track segments (curve and tangent sections) and track points (obstacles and, possibly, grinding checkpoints), the second set of track segments will replace the first, but the second set of track points will be added to the first, which may result in redundant points.