tldr version: Sitting in pit lane near Start/Finish line corrupted a lap recording. Check database deleted all OBD2 and GPS data for all session over the whole day. No backup.
Long version:
After my last and for me most important track evening of the year, I tried to back up the evenings' data before driving home.
I would usually send myself the data, then back up the database. This time for some reason (tired), I tried to back up the database, then send myself the lap data. I pushed the icon in the Lap List that looks like the Local Backup button in the Databases screen. I now understand that this is actually the Check Database button.
It immediately, with no prompt, started checking the database. It found some corrupted data and deleted all the GPS and OBD data for the day. Multiple laps across multiple sessions. I know that there was nothing wrong with most of those laps, because I had been looking at the data and video between sessions. All that remains is the lap times and the splits.
There does not seem to be any backup made before it deleted.The most recent System backup is from the 2nd of September, and does not contain the data.
So what caused the corruption?
There was one weird 715827:42.85 lap which got recorded when we are forced to wait in the pits, which is very close to the start line. Variations in GPS position can trigger a lap when you are sitting near the start line, as I reported in the Beta testing thread "New Custom Tracks - Can't edit because recording starts" . I think this is the one that caused the error, I got a message, something like "Current lap had data problems, invalid lap.... ...please contact Author" error message (I did not screen shot it and I can't see the screen very well with my driving glasses on). Allow Low Speeds is OFF.
It does not make sense that one bad lap in a late session should corrupt multiple sessions of the whole track day?
As I was leaving the track (they close the track and we drive out over the starting lanes), HLT went into crazy mode like I reported in the beta thread - recording starting and stopping with several 715827 second laps. Again, "Allow Low Speeds" is OFF, I think GPS disturbances when stopped or moving slow near Start/Finish lines can also cause this.
Check Data deleted all sessions of Track Day
Re: Check Data deleted all sessions of Track Day
I assume you have checked for Automatic Backups in Administration / Databases?
It sounds like there is some problem with this type of lap triggering resulting in corrupted lap entries. Check Data tries to match lap entries with data recordings in case it finds inconsistencies. Due to this ill-formed lap it probably considered your latest recordings as widow entries and purged it. So two actions for me: find the problem with laps being triggered while in the pits (and resulting corrupted lap entries), plus adding an automatic backup ahead of every Check Data.
I’m sorry for the lost data, at least you should have your lap times listed..,
Harry
It sounds like there is some problem with this type of lap triggering resulting in corrupted lap entries. Check Data tries to match lap entries with data recordings in case it finds inconsistencies. Due to this ill-formed lap it probably considered your latest recordings as widow entries and purged it. So two actions for me: find the problem with laps being triggered while in the pits (and resulting corrupted lap entries), plus adding an automatic backup ahead of every Check Data.
I’m sorry for the lost data, at least you should have your lap times listed..,
Harry
Re: Check Data deleted all sessions of Track Day
No problem Harry, I understand how these things work 
I did check for automatic backups yes. I tried reloading from the latest one, but it did not contain anything from last night.
A couple of knock on effects of these events which may or may not be relevant:
-Having reloaded from my saved database to at least keep the Lap times and Splits, now every lap has a duplicate - there are two of each one.
This was because I opened the Lap List that I sent to myself after the Data Deletion
-Also, the session information is gone, so I can't overlay the Video data more than one lap at a time.
When I fixed the double lap issue, this kind of got fixed.
-My colleague had the exact same crazy triggering issue with a few 715827 minute laps, he was running 22.03, I was running 22.04.
-We both use the same custom track, Sviestad 2, which is one I made. It has never given any problems before, except an "Information Unspecified" POI which flashes momentarily in the overlay. I mention this, because the "Information Unspecified" occurs at the Start Finish line, intermittently. Example in this video at 6:30, where usually, like the previous lap at 5:18 had no sign of this.
https://youtu.be/Z1OFgTKJKyI?t=6m30s
I prefer this home made track because I don't like the splits and labels in the official track.
If there is anything else I can do to help let me know.
I did check for automatic backups yes. I tried reloading from the latest one, but it did not contain anything from last night.
A couple of knock on effects of these events which may or may not be relevant:
-Having reloaded from my saved database to at least keep the Lap times and Splits, now every lap has a duplicate - there are two of each one.
This was because I opened the Lap List that I sent to myself after the Data Deletion
-Also, the session information is gone, so I can't overlay the Video data more than one lap at a time.
When I fixed the double lap issue, this kind of got fixed.
-My colleague had the exact same crazy triggering issue with a few 715827 minute laps, he was running 22.03, I was running 22.04.
-We both use the same custom track, Sviestad 2, which is one I made. It has never given any problems before, except an "Information Unspecified" POI which flashes momentarily in the overlay. I mention this, because the "Information Unspecified" occurs at the Start Finish line, intermittently. Example in this video at 6:30, where usually, like the previous lap at 5:18 had no sign of this.
https://youtu.be/Z1OFgTKJKyI?t=6m30s
I prefer this home made track because I don't like the splits and labels in the official track.
If there is anything else I can do to help let me know.
Re: Check Data deleted all sessions of Track Day
Importing .hlptrl files is an additive operation - that's the reason you get duplicates when importing it on top of a non-empty database. Sessions are identified by comparing the end and start of consecutive laps. For duplicates, the these do not match and you will get something like 2 lap sessions.
To analyze the odd triggering behavior, can you please export all your POI / track sets and send them to Harry@gps-laptimer.de. You can send track sets by using the certify mechanism (Lap List ‣ any track header ‣ User track set ‣ Certify. Please change the mail address from Tracks@gps-laptimer.de to Harry@gps-laptimer.de
- Harry
To analyze the odd triggering behavior, can you please export all your POI / track sets and send them to Harry@gps-laptimer.de. You can send track sets by using the certify mechanism (Lap List ‣ any track header ‣ User track set ‣ Certify. Please change the mail address from Tracks@gps-laptimer.de to Harry@gps-laptimer.de
- Harry