TFDMemtable does not save indexdefs definitions

[Stéphane Wierzbicki 45]

Hello,

 

Does anyone know how to store a TFDMemtable with its indexes?

 

TFDMemtable.SaveToFile does not save indexes, I tried different formats ( sfXM,sfBinary,sfJSON).

I've also tried to either add indexes with TFDMemtable.IndexDefs or with TFDMemtable.Indexes. 

 

StoreItems is set to [siData, siDelta, siMeta].

 

I'm clueless. Any idea?

 

 

[Stéphane Wierzbicki 45]

@Dmitry Arefiev do you know maybe a workaround? 

[Uwe Raabe 2057]

AFAIK, IndexDefs (as well as FieldDefs) are stored in the DFM when StoreDefs is True, but I guess they are not part of the data file.

[Stéphane Wierzbicki 45]

@Uwe Raabe this could be an explanation but this can't be the reason why they are not stored (BTW FieldDefs are stored in the saved file).

The only solution I'm thinking to is to create a separate list that will hold indexes information. This is cumbersome as this could be done with the TFDMemTabble.SaveToFile method. 

[Guest]

Are you using it w/o sources?

[Bill Meyer 337]

For reasons I have never understood, the TDataset and its descendants stream data, but not properties. In my own work, I have had to deal with this in connection with the field properties we wish to pass to reporting code. It is all very nice to have Alignment, DisplayFormat, and DisplayLabel, but rather annoying that there is no option to include them in streaming.

[Stéphane Wierzbicki 45]

Looks like a feature request to put on quality central...