On Tue, 3 Jul 2007, Joost van der Sluis wrote:
> On Tue, 2007-07-03 at 17:38 +0200, Michael Van Canneyt wrote: > > > What I do like is the idea of storing strings in a > > > widestring/ansistring. I tried to implement that earlier, but it's > > not > > > doable in a Delphi-compatible way. As you said, you don't have that > > > problem. But it's still something on my whish-list for > > > sqldb/TDataset/TBufDataset. There must be a solution, without using > > the > > > blob-system... > > > > I do not think this is a good idea: the amount of memory used for this > > is > > a multiple of the classic buffer scheme, the heap will be terribly > > fragmented. > > The buffer system is exactly meant to save memory (blobs excepted). > > Do you think? Using the buffer, there's a lot of memory which isn't > used. Not more than when using ansistrings - or worse, widestrings - to store the string data. You forget the heap overhead and ansistring "hidden" data, plus the whole reference counting mechanism. > I thought about adding a new kind of fieldtype, for example > ftAnsiString which you could use for larger strings. > But maybe you can use a ftMemo in that case.... Memo is very special and hard to handle in grids and the like. See my private mail to you for a more detailed calculation. > > > > What do you mean with the local change log and data file? > > > > Like TClientDataset: the changes to the records (the delta) are kept > > in a > > separate index. All can be written to file. It's a briefcase model. > > I thought so. TBufDataset also has that, it can't save it to file, > though. But that's easy to implement. Indeed. All one needs is some time :-) Michael. _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
