Rob Fitzpatrick
ProgressTalk.com Sponsor
An issue crossed my desk yesterday. I was given a database backup file (made with probkup) and asked to restore it. I know that it's several years old and "probably" came from a Windows box.
Do I need to prorest it with exactly the same DLC version that was used to created it? If not, how close do I need to be (same major version, same minor version, same service pack)? And does the fact that prorest succeeds and I can open the database constitute sufficient evidence that I used the same DLC version as whoever ran the probkup? Or could there be silent corruption I can't see?
Is there a way to determine anything about the backup from its internal structure?
I ran strings on the backup file and sifted through the output. One helpful hint was a list of system tables. I found references to _Code-Feature and _Database-Feature, which means the DB was at least v10. I found _Area-Threshold, which means it was at least 10.1A. But I didn't find _UserTableStat, which was introduced in 10.1B.
So it is possible that this DB was backed up with 10.1B, and had just never had its VST schema updated in 10.1B. But given the date of the file and the probable time we upgraded to 10.1B (before my time), my best guess is that it's a 10.1A backup.
I'm just curious if anyone has had a requirement like this in the past, and has an easier way of getting the answer. This kind of sleuth work is a pain in the butt. I have easy access to many different Linux DLC versions, so trial and error is not a problem there. But on the Windows side I only have a few recent ones, so I'd rather avoid multiple ESD downloads if I can.
Do I need to prorest it with exactly the same DLC version that was used to created it? If not, how close do I need to be (same major version, same minor version, same service pack)? And does the fact that prorest succeeds and I can open the database constitute sufficient evidence that I used the same DLC version as whoever ran the probkup? Or could there be silent corruption I can't see?
Is there a way to determine anything about the backup from its internal structure?
I ran strings on the backup file and sifted through the output. One helpful hint was a list of system tables. I found references to _Code-Feature and _Database-Feature, which means the DB was at least v10. I found _Area-Threshold, which means it was at least 10.1A. But I didn't find _UserTableStat, which was introduced in 10.1B.
So it is possible that this DB was backed up with 10.1B, and had just never had its VST schema updated in 10.1B. But given the date of the file and the probable time we upgraded to 10.1B (before my time), my best guess is that it's a 10.1A backup.
I'm just curious if anyone has had a requirement like this in the past, and has an easier way of getting the answer. This kind of sleuth work is a pain in the butt. I have easy access to many different Linux DLC versions, so trial and error is not a problem there. But on the Windows side I only have a few recent ones, so I'd rather avoid multiple ESD downloads if I can.