David Smith wrote:
A bit unrelated question, why are you using TFDQuery +
Clientdataset?
Almost everything you can do with CDS now you can do with TFDQuery,
you are just using more memory.
Lajos, good afternoon. The simple answer is I don't know! I had
always used the TADOQuery (etc) components having only ever written
LAN type querying but when I got Delphi Berlin I wanted to write
applications that in theory could save data locally, and then when
re-connected to the network, could upload changes back again. I
bought Cary Jensen's 'Delphi in Depth: ClientDataSets 2nd Edition'
book and have been following that for guidance.
Is TFDQuery a memory based 'table' in its own right? Are you aware of
any differences between the two (CDS and TFDQuery)? A lot of examples
on the WEB do use the combination I have - so I was just copying them
in an attempt to get it all to work.
Thanks for your comments and can anyone shed any more light on this
please? I'd like to start off using ClientDataSet like work by using
the latest components if I have them rather than using old ideas and
old components?
I never tried the briefcase model. In theory FDQuery can also save its
content to a file, but never tried how difficult is to load and apply
back to the server.
TFDQuery stored the data in a memory based table (TFDDatSTable). I
never used advanced options of the clientdataset so cannot comment how
different it is. I am sure you can find things that are implemented
better in CDS (for example nested datasets that I've never used).
While there are more examples for the CDS it's "almost" deprecated
(sometimes there are bug fixes for it, but that's a rare case. There
are reports that CDS has access violation when compiled for a 64 bit
targert in Berlin, I have no information whenever those bugs are
resolved in Tokyo or not) on the other hand there is less example for
TFDQuery but it's part of the FireDAC that's actively developed.
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