[mythtv-users] Lesson Learned from my Upgrade from Jaunty To Karmic...

[Michael T. Dean]

On 11/21/2009 09:30 PM, David Herman wrote:
> I was running Jaunty with trunk for ever (really, forever -- at least 
> as long as Jaunty was out).
> When I upgraded, I did the old, back up the database, reformat the 
> hard drive and install path.
>
> An interesting thing happened... For some obscene reason, my 
> mythconverg database chose to be case sensitve.

That means your database schema is broken.  MythTV /never/ had any 
case-sensitive columns in the database schema until 0.22.  Now, in 0.22, 
there are a few columns that are case sensitive, and they're very 
unimportant columns.  (And, definitely not any of the columns in the 
settings table.)

> One may wonder what the big deal is, but all over the myth code, 
> people were not consistant in DBSchemaVer (as well as other settiings)..

Uh, where?  I can almost guarantee that for DBSchemaVer there's /never/ 
any place that capitalizes it incorrectly.  I'm 99% positive that's true 
of all other settings, too.

> So everytime I would bring up a frontend, it went and tried to 
> upgrade, but since it could not find the version, it flipped out and 
> started hacking away at my data. I ultimately did a PARTIAL recover 
> and that seemed to fix things (of course, I had to drop the database 
> first, rerun mythtv-setup, re-add my tuners, channels, etc...). I 
> still do not understand what happened to change the behavior of Mysql 
> during this process

The partial restore (done properly, as documented at 
http://www.mythtv.org/wiki/Database_Backup_and_Restore#Partial_restore_of_a_backup 
), would have fixed a broken schema.  If your database is still case 
sensitive, you have bigger issues (i.e. broken MySQL--such as a MySQL 
without the utf8_general_ci collation installed--meaning MythTV will 
/not/ work properly).  You need to fix that now or you will be 
corrupting data.

> I am not trying to throw stones, so please don't take offense. I 
> realize people are spending time away from loved ones when they donate 
> their time to this project. I think this project is by far one of the 
> best collaborative efforts I have been a user of.
>
> I propose two things. 1) Don't mix case in any setting in the settings 
> table.

We don't.  If there are some cases where settings names aren't properly 
capitalized, they're typos that should be fixed, but it won't have any 
negative effects since they're all using utf8_general_ci collation.

If you'd like to point out some typos, I'll fix them.  Otherwise, I'll 
find them in my settings review that I'll be doing in a month or so.

> 2) An effort be made to change every reference in code to lowercase 
> values for items in the settings table.

No real need since they're not case-sensitive...  And, IMHO, DBSchemaVer 
is /much/ easier to read (and fits with the MythTV coding policies, so 
shouldn't be hard for a Myth coder to remember) than dbschemaver or 
nopromptonexit or whatever.

But you do need to fix whatever's wrong with your database.  Broken 
schema or broken server/installation.

Mike