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Re: SqlArray Join [message #4115 is a reply to message #4112]

Fri, 21 July 2006 17:16

rbmatt
Messages: 90
Registered: July 2006
Location: Tennesse, USA

Member

luzr wrote on Fri, 21 July 2006 08:33

OK, I hope I have found it.

Thanks so much

luzr

Anyway, the bug is caused by wrong placement of

	list.CListView.Query();

You are performing the query _before_ you join with detail. Query sets the cursor to the first row, means detail will not get loaded for this row....

Putting it at the end of constructor fixed the problem.

Makes sense now Wink

luzr

I have taken the oportunity a tried to improve the code a bit:

Wow, thanks a million.

luzr

Most application do not use more than single DB engine, therefore it is a good ideal to define default session - you do not have to se it everywhere ("SQL=session").

Makes sense, good tip.

luzr

Opening session in constructor is really bad thing Smile

I guess this is also because there will only be one DB session but possibly multiple instances of my app window, also performance.

luzr

BTW, is your database schema fixed in existing .db file, or is it a part of application you are developing? U++ has nice support for schemas... I would be happy to help you with that...

I have lots of data that is currently in a spreadsheet. I will use php or perl to parse it out into a usable CSV or something similar. The actual structure of the DB can still be changed. The reason I did not opt for schemas was because I thought it might add a little extra (code size, memory usage) to the final product. If all the processing is pre-compile, it might be beneficial to add it in here. Advice?

luzr

...because, in fact, it would not be a bad idea to finally add some nice SQL example to U++ Smile

I'll be glad to offer my app as a tutorial and help write it.

Thanks again

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