Odd bug sometimes stops Photos from opening or repairing library on SD card

[RedTomato]

I have a 2013 MBA with 128GB SSD.

Photos stores its system library on a 200GB SDXC card in the side slot of the MBA, specs as follows:

- SanDisk Ultra 200 GB MicroSDXC UHS-I
- Nifty MiniDrive Air Silver MicroSD Card Adaptor

Every now and then, opening Photos causes it to throw a wobbly, and it will say something like 'Photos cannot open or repair this library, please quit or select a different library.' Quite scary when you have 5000 photos in the library. Restarting doesn't seem to fix it. Pressing option-cmd and clicking on the library file starts the repair process, then at 5% it halts saying something like 'This library cannot be repaired'.

The only fix seems to be to take out the Nifty MiniDrive and re-insert it. This seems to reset something, and then Photos is able to open the library again, no repair needed.

MBA is currently on Macos 10.13 High Sierra, but this also happened on either 10.12 Sierra or 10.11 El Capitan (can't remember which version it was running before doing a major update a few weeks ago).

Quite disturbing. Any thoughts?

 

[Fishrrman]

"Quite disturbing. Any thoughts?"

My thoughts:

I personally wouldn't use the setup you're using for library storage -- too unreliable. Too many things to "go wrong" on you -- the SDXC micro card; the adapter card.

I'd switch to some kind of USB3 drive instead, either an "all in one" solution, something like this:
https://www.amazon.com/exec/obidos/ASIN/B00ZTRY532?tag=delt-20

... or, buy a 2.5" "bare" SSD and a USB3 enclosure that support UASP, and "roll my own" drive.

Granted, you now have an external device which has to be plugged into the MacBook.
BUT -- probably fewer problems.

At the very least, keep the setup you have now and get something else to back it up onto (like the drives I suggested above). Remember that ONE COPY OF THE LIBRARY IS NOT ENOUGH.

ANOTHER THOUGHT:
High Sierra has been reported by some to be quite "flaky" in how it handles the mounting/dismounting of USB drives. I believe the card slot is "seen" by the OS as if it were another USB connection (I could be wrong).
The problems you're experiencing may be due to a quirk in High Sierra, and have little to do with the Nifty card setup.

Try this:
Next time Photos "objects" to the card (i.e., doesn't open the library), try this:
1. Quit Photos
2. Open Disk Utility
3. Do you "see the presence" of the Nifty?
4. If Disk Utility can't see it, perhaps the OS has "unmounted" it.
That would explain why Photos can't see it, either.

There is something out there called "Mountain" -- a small utility that can mount/unmount external drives. I'm wondering if this could be used to "re-mount" the SD card?

Also -- have you gone to the energy saver preference pane and UNCHECKED the option to "put disks to sleep when possible"?