[mythtv-users] debugging duplicate recordings

[Joey Morris]

"Michael T. Dean" <mtdean at thirdcontact.com> wrote on Fri, Aug 21, 2015 at 09:36:46AM -0400:
> On 08/21/2015 08:13 AM, Joey Morris wrote:
> >Here's where I'm still confused. Is Myth now deciding these are duplicates
> >because the subtitles and descriptions match? It shouldn't fall back to the
> >subtitles and descriptions, because the episodes have non-generic, matching
> >program IDs. Or do you have to set Duplicate Matching to something other than
> >"Don't match duplicates" before even the program ID check is enabled? I assume
> >this is the case. And OK, it sounds obvious now that I've written it out. In my
> >defense, however, this detail is omitted in the recording rule setting, on the
> >wiki page, and in Mike Dean's spiel about duplicate matching. From the wiki:
> >
> >   The program ID is the definitive identifier of an episode. If the current
> >   episode described in the listings and a previously-recorded episode both have
> >   non-generic program ID's, then only the program ID will be compared to
> >   determine if the program is a duplicate. In this case the duplicate-matching
> >   method specified by the recording rule will be ignored.
> >
> >I interpret the "duplicate-matching method specified by the recording rule" to
> >mean *any* of the choices for the duplicate matching setting, including "Don't
> >match duplicates".
> 
> "Don't match duplicates" isn't a duplicate-matching mechanism.  It's an
> explicit disabling of duplicate matching.  Therefore, if duplicate-matching
> is disabled, there is no duplicate-matching mechansim specified.

Right. Like I said, it seems obvious in retrospect. However, the original
language didn't use the word "mechanism". It used the word "method", which I
interpreted more like "setting". If you change "method" to "setting" in the
text, then I think it's easier to see how I interpreted the sentence
incorrectly: "In this case the duplicate-matching setting specified by the
recording rule will be ignored." Because "Don't match duplicates" is a valid
duplicate-matching setting, I thought this setting would be ignored, too.

Futhermore, the text for each of the four fallback method choices (subtitle,
description, etc.) omits the fact that program ID will be checked first. It's
not that much of a logical leap to think the fifth choice in that dropdown
follows the same pattern and omits the program ID check. Since "Match duplicates
using subtitle" is really "Match duplicates using program ID, and if that
doesn't work, then match duplicates using subtitle", why couldn't "Don't match
duplicates" mean "Match duplicates using program ID, and if that doesn't work,
then don't match duplicates (using subtitle or description)"?

Anyway, I've belabored the point long enough. I updated the duplicate matching
wiki page by adding the Setup section and by adding a word to the quoted
sentence above:

    In this case the duplicate-matching *fallback* method specified by the
    recording rule will be ignored.