dhis2-devs team mailing list archive

[Bob Jolliffe <bobjolliffe@xxxxxxxxx>]

2010/4/12 Lars Helge Øverland <larshelge@xxxxxxxxx>:
>
>
> 2010/4/12 Bob Jolliffe <bobjolliffe@xxxxxxxxx>
>>
>> I had a go at this earlier with reasonable success.  You have to make
>> an uncompressed pg dump with insert statements (these are both
>> optional parametrs to pg_dump).  Some very slight adjustment to the
>> structural metadata - I'll document later if people are interested -
>> and then tried to import data.
>>
>> Only one snag - pg has its own peculiar way of handling binary strings
>> (bytea fields) which h2 doesn't emulate.  Can't blame h2 too much -
>> what pg does is a bid weird.
>>
>> This affects systemsettings, usersettings and reportsettings.
>>
>> Other than that I imported 1.5 million datavalues and associated
>> dataelements, orgunits etc.
>>
>> The h2 guys are aware of the bytea compatibility problem and have the
>> issue roadmapped - apparently they will bump it if it something people
>> request.  I guess I should request.
>>
>> If I was really pushed I could write a script to find all the binary
>> strings in the pg dump and try to convert them to something h2 is
>> happy with.
>>
>> Having said that, I think all the places where we currently use binary
>> strings are really unnecessary (storing evil java serialized objects)
>> which I think have a historical rationale.  It should be relatively
>> easy and desirable to change these - particularly as we also want to
>> represent these things in xml - but we'd have to consider the effect
>> on compatibility with legacy dhis databases which have the blobs.  I
>> guess we'd need an upgrade script of some sort.
>>
>> So the prognosis is good but not quite seamless yet.
>>
>> Cheers
>
> This is great news. The system settings should def be no show-stopper here.
> First they could simply be omitted as they probably will be set individually
> anyway, second we could migrate to string as we have never really used
> objects as settings.

Hi Lars

True.  system settings should be least disruptive.  Sorry I meant
reporttable (rather than report setting!).   We are using a serialized
java object to represent the dimension type which also seems a bit
strange.  How do (non java) db clients like excel deal with these?
I'll have another look tomorrow, but you will know better the
rationale.  I'm guessing its related to the whole casting thing that
we are doing with dimensions.

Cheers
Bob

> Lars
>