[fpc-pascal] TSQLQuery and buffering.

[Martin Schreiber]

On Saturday 25 March 2017 10:28:37 Michael Van Canneyt wrote:
> On Sat, 25 Mar 2017, Martin Schreiber wrote:
> > On Saturday 25 March 2017 09:32:33 Gary Doades wrote:
> >> I Understand about the "normal" use of TSQLQuery and data sets and I
> >> also use this for small result set that need the data changing some way
> >> and writing back to the DB. What I need now is an equally convenient and
> >> powerful way of processing "big data".
> >
> > MSEgui has TSQLResult for that purpose without the TDataset overhead.
> > https://gitlab.com/mseide-msegui/mseide-msegui/blob/master/lib/common/db/
> >msesqlresult.pas
>
> Can you explain in 2 words how this differs from TDataset ?
> At first sight it is not fundamentally different.
> The structure looks almost exactly the same, just the names are different.
>
Please follow the datatransfer from database to the destination in application 
in T*Dataset and compare it with TSQLResult and you probably will see the 
difference.

> And while you're at it, please explain what the 'overhead' is of TDataset.
> That TBufDataset introduces overhead is a design decision. But TDataset
> itself introduces no "overhead".
>
TDataset/TDataSource/TDatalink/TField is a complex machine, don't you think? 
Follow the code of a TDataset.Next() call step by step and you will see what 
I mean.

Martin