I haven't used Ratings much on any of my media, but I was looking at [Date First Rated] recently and it doesn't seem to be updated correctly. I assume that it is supposed to be blank until a rating is added to a file, at which time a Date and Time value will be saved to the field.
Pretty much the only information I can find about the field is when it was introduced. Maybe nobody has really used or tested it since then?
20.0.5 (8/4/2014)
1. NEW: Added 'Date First Rated' field.
What I am seeing is that on my HTPC where I have 27,803 audio files, 969 have a [Date First Rated], but only 23 files actually have a value in the [Rating] field. One had a [Rating], but no [Date First Rated] until I changed the Rating. I guess the [Date First Rated] could be coming from YADB or MusicBrainz when I do lookups, but I believe that Ratings aren't updated from these sources, so the [Date First Rated] shouldn't be either. Most of these audio files are MP3s I inherited from my brother, which were then imported into MC when I set it up.
In fact, all files that have values in [Date First Rated] that I can't explain were imported after May 1st, 2017, but I hadn't imported anything between November 2015 and the first occurrence on May 7th 2017. Maybe something changed in MC around that time.
On my Workstation where I have done a lot of CD rips, the [Date First Rated] seems to be the Date and Time that a CD rip started for all Tracks, or maybe when the disc was first detected by MC as the Date and Time match records in the CD Database, while the [Date Imported] seems to be the Date and Time that each Track rip was finished. These rips were also done after May 2017.
For the 7516 Video files on my HTPC, 3161 having a [Date First Rated] value, and of those 156 actually have a [Rating] value. Of those with a Rating, most are TV Shows, with only two Movies and one Music Video. So 3005 have a [Date First Rated] value and no [Rating] value, confirmed both by math and a search. I believe all of the 156 files that actually have a [Rating] value are programs that I manually rated. Most are the Doctor Who series.
In most cases for video files the [Date First Rated] matches the [Date Imported] almost but never exactly. The time matches to the minutes but a comparison of the two fields doesn't find any exact matches, so they differ by seconds. Testing for a non-exact match lists all 7516 videos. In the case of TV recordings, the [Date Imported] matches the start time of the recording, and the [Date First Rated] matches the end time, bot including padding times.
So for video the [Date First Rated] appears to be set to the current Date and Time shortly after the file is imported, except for TV recordings where it is set shortly after the recording finishes.
Anyway, I don't think the functionality around the [Date First Rated] field is working as the name would imply. It looks like it was broken between November 2015 and May 2017. Thoughts?