[Lazarus] Problem with zeos and sqlite-3

[Frank Church]

On 16 February 2013 13:51, Sven Barth <pascaldragon at googlemail.com> wrote:
> On 16.02.2013 14:41, Joost van der Sluis wrote:
>>>
>>>
>>> In our WinCE client for our application we use it for a miniature
>>> version of our database. As the client does not need all tables and only
>>> a specific subset of the data we generate a database on the host
>>> computer and download that to the device. When the user is done the
>>> database is copied back and the created data is integrated with the
>>> normal database (which is either a Oracle, MSSQL or DB2 one).
>>
>>
>> What you could do is: use TSQLQuery to perform a query on Oracle or MSSQL.
>> Then store the dataset to file. Then copy this file to your WinCE client.
>> Then you can work with it on your client, but don't use ApplyUpdates but do
>> save your dataset to disk. When you're done, copy the dataset to another
>> computer. Open the dataset into an TSQLQuery and run ApplyUpdates...
>
>
> We are using not only one table, but multiple ones with references in
> between them. Also not every data needs to be loaded each time and the
> exported amount of data can get huge depending on the customers existing
> database. Also we don't directly write the created/modified data back into
> the main database, but go through a special "import interface" that's
> designed for input from mobile devices and our web frontend (because
> depending on the type of created/modified data specific other actions need
> to be triggered which would not be possible if simply doing a ApplyUpdates
> as tables are touched that are not downloaded to the mobile client).
>
>
>> But this only works if you do not use SQL on your WinCE client. But maybe
>> this can be solved since ZMSQL adds that functionality to TBufDataset? (I
>> only read the wiki-article, never actually looked at it)
>
>
> As I wrote: ZMSQL sounds interesting. But up until now I've also only read
> the wiki article.
>
> Regards,
> Sven
>
>
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The nature of SQLite means your client library has to do a very good
job of checking the table definitions and ensuring that and ensuring
that the right conversions are made when reading and writing records
in accord with standard TDataset expectations, and I don't think the
clients do a perfect job with SQLite.

It can be convenient though.

-- 
Frank Church

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