GDA Missing records in SQLite

[Phil Longstaff]

Graham Leggett wrote:
> Phil Longstaff wrote:
>
>> There is a function to query the backend to see what features it 
>> supports, but prepared statements is not in that list.  Also, if we 
>> require prepared statements, that might cut out the sqlite backend 
>> because a libgda modification to use it might not propagate out far 
>> enough.  I know Derek wants to see the xml gnucash file replaced by a 
>> sqlite db, so we need to be really sure it is unusable before we 
>> disqualify it.
>
> A quick Google search shows a number of references to prepared 
> statement use in sqlite, which suggests to me that prepared statements 
> are supported.
>
> Two things worry me at this point about the current behaviour of libgda:
>
> - Row inserts are failing, but the error is not communicated back to 
> the caller. As a result, the database is corrupted in the process.
I'm not sure the error is not communicated back.  In an e-mail from Mark 
Johnson with msg-id <47BCA52E.6010806 at shaw.ca>, he said there is an 
error message written to /tmp/gnucash.trace.  I agree with him that that 
is not sufficient warning that there has been a problem.

Note that on the flip side, the postgresql backend seems to return 
normal status as an error indication so that there is lots of stuff in 
/tmp/gnucash.trace.
>
> - libgda doesn't seem to (yet) guarantee that prepared statements are 
> used, and therefore that parameters do not need escaping.
>
> The data being saved is financial data, and people are using this data 
> to file tax returns and various other mandatory stuff that could prove 
> expensive if done incorrectly. Gnucash should be treating this data 
> conservatively, and should only be using backends that can give some 
> kind of certainty that data won't be corrupted for any reason.
>
> If we have to temporarily disable a backend until that backend works 
> correctly, it is the safest thing to do, and offers an incentive to 
> get the backend fixed.
I think I can come up with a libgda patch which will escape/unescape 
strings properly for sqlite and I'll submit this to the libgda project.  
Makes config mgmt during testing and for gnucash execution more 
difficult because because of the dependence on the specific version of 
the library, though I suppose there is already this problem with other 
libraries.  Maybe we can ask libgda to release a 3.0.3 version with this 
patch in the near future so that people can test with an official libgda 
release rather than a patched one.

Phil