[mythtv-users] export/import of selected MythTV data

[Stephen Worthington]

On Wed, 05 Aug 2015 10:29:37 -0600, you wrote:

>On Wednesday, August 05, 2015 04:47:10 PM Stephen Worthington wrote:
>>
>> >Now I don't know if it's worked because after picking Upgrade a couple
>> >times, and a delay, I'm given to a screen that's probably the new
>> >MythFrontend but it's heavily corrupted. I can make out a MythTV logo
>> >and "Main Menu" at the top, repeated, along with the graphics and text
>> >below it repeated. I can press [Esc] and barely make out the "Do you
>> >want to go back?" prompt. Eventually I can get out, answer a couple
>> >prompts for starting the backend and doing a mythfilldatabase.
>> >
>> >Does this mean it worked?
>> 
>> Are you using mythtv-setup to do the upgrade?  Do you have MythMusic
>> or other frontend only plugins installed?
>> 
>> Using mythtv-setup to do database upgrades is the recommended way, as
>> it normally gives a little more control over the process.  An
>> 
>> If you have MythMusic installed, or other frontend only plugins, then
>> you need to also run mythfrontend after mythtv-setup to get their
>> databases upgraded.  If you run mythfrontend first to do the upgrade
>> with MythMusic installed, then I found you can get a deadlock
>> situation - but I am not sure what MythTV version that happened on.
>
>I only used mythtv-setup. I did and will use MythMusic and MythGallery 
>though they all pointed to a Samba share so they have no content data. I 
>had all the other plugins installed too, though unused.

MythMusic has database tables that have been updated.  I think
MythGallery's table(s) have not changed for a long time, but I am not
sure about that.

>I was able to run mythconverg_backup.pl on the converted database without 
>complaint. 
>
>Do I still need to run mythfrontend once to upgrade plugin DB items?

Yes.

>What if I don't care about old data from these plugins? Can I skip that 
>step and just go forward with empty tables for plugins? Or will I get bad 
>tables?

You still need to update the schema even if the tables are empty.
Schema changes affect the table structure, as well as updating the
data if necessary.  If you do not do the schema changes and upgrade
the MythTV version to 0.27, the later versions of the plugins will not
have the necessary code for changes from 0.21 plugin schemas and the
plugins will not work.  My experience is that if plugins are having
trouble with their tables, they can cause mythfrontend as a whole to
fail to run, and then you would have to uninstall the problem plugin
and reinstall it to fix that.