Hopefully I am asking this question correctly...
I have a folder with hundreds of video files of type .mp4, .mkv, .avi, etc. I have 2 columns → Dimensions and Duration. Every time I enter this folder, all of the data in these 2 columns have to get repopulated. Is it possible to cache this data somehow so it doesn't have to get refreshed every time?
No, not currently. (At least without some fairly elaborate scripting.)
It is something we've been thinking about, although not for the near future as there's too much else going on at the moment.
Bummer! Thanks anyway. Do I detect a major update coming up? Is that the 'too much else going on?'
There's always work on those going on, as well as on new free updates to the current version. Nothing is imminent. 
You could try getting the columns via one of these add-ins. Both cache the metadata.
Thank you for your help!