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Posted: **29.01.2021, 20:57**

Hello,

Just a few remarks for the new TZMemTable component:

- ftMemo, ftString, ftFixedChar will throw a nullpointer exception upon opening:

Code: Select all

 ZMemTable1.FieldDefs.Add('MyField', ftString);
 ZMemTable1.Open;

Issue is in ZMemTable.pas : 208

Code: Select all

        else if Current.DataType in [ftMemo, ftString, ftFixedChar] then
          ColumnInfo.ColumnCodePage := GetTransliterateCodePage(Connection.ControlsCodePage)

TZMemTable has no connection, so Connection.ControlsCodePage is referring to nil.ControlsCodePage. Lines 208 and 209 can be deleted, items can be merged with the next condition:

Code: Select all

        else if Current.DataType in [{$IFDEF WITH_FTWIDEMEMO}ftWideMemo, {$ENDIF}
          ftWideString{$IFDEF WITH_FTFIXEDWIDECHAR}, ftFixedWideChar{$ENDIF}, ftMemo, ftString, ftFixedChar] then
          ColumnInfo.ColumnCodePage := zCP_UTF16;

- The above also renders the condition in : 217 useless, as it will never be true:

Code: Select all

    if (Connection <> nil) and (Connection.Connected)
    then AConSettings := Connection.DbcConnection.GetConSettings

I created a small patch with the above, will issue a pull request soon.

With that said, I have the following code:

Code: Select all

 ZMemTable1.FieldDefs.Add('MyField', ftString);
 ZMemTable1.Open;
 ZMemTable1.Append;
 ZMemTable1.FieldByName('MyField').AsString := 'Hello, world!';
 ZMemTable1.Post;

I have a DataSource and a DBGrid connected, and it is showing that 'MyField' is WideMemo instead of String, which I explicitly created:

The reason is, ConvertDbcToDatasetType sets the fieldtype as WideMemo, if there is no length specified. I can see the reason, just want to ask if it is intended?

Code: Select all

ZMemTable1.FieldDefs.Add('MyField', ftString, 200);

Works as planned.

Posted: **05.02.2021, 06:25**

Thanks for the feedback!
As my commit says: it was a 20 min job

I found some more inconsistencies in other components too

TZStoredProc has an UpdatSQL property
TZStoredProc has no Transaction property
TZStoredProc has OnPostError Event property
TZMemTable has an UpdatSQL property
TZMemTable has OnPostError Event property

Just to name some i have seen.

. That than meens there is an issue with the alltime inheritance model of some of the components.
According the AV's thanks for the temporary fix. Using the W-Fields hides theses issues. I'am working on it, including a connection property for TZMemTable.

aehimself wrote: ↑29.01.2021, 20:57 The reason is, ConvertDbcToDatasetType sets the fieldtype as WideMemo, if there is no length specified. I can see the reason, just want to ask if it is intended?

Yes it is. The TString/WideString-Field need a size for a buffer. Otherwise you would get an exception on creating the fields.

Posted: **05.02.2021, 08:25**

EgonHugeist wrote: ↑05.02.2021, 06:25 Thanks for the feedback!
As my commit says: it was a 20 min job :P

...and you can't imagine how happy your 20 minutes made us, end users :)
There were lots of people waiting for this feature, so yeah, thank you again!
I already included it in one of my projects, replacing an in-memory SQLite connection :)

EgonHugeist wrote: ↑05.02.2021, 06:25I'am working on it, including a connection property for TZMemTable.

Does it need one? Or it'll be optional? In my view the main advantage of a memtable that it is 100% functional without a connection and therefore can be used to de- and reconstruct data tables from any source.

Posted: **05.02.2021, 09:23**

The most important are the methods of copying (with filtration) and even better using SQL (but it's already pretty high-grade stuff) from and to local sources(datasets). Some do this by putting SQLite underneath.

Michał

Posted: **11.02.2021, 05:33**

Hallo. I will also add.
In TZMemTable when displaying fields of type TZRawStringField, the program gives an error AV. See screenshot.

Posted: **11.02.2021, 09:43**

I think this was just fixed:

https://sourceforge.net/p/zeoslib/code-0/7313/

Posted: **12.02.2021, 05:53**

EgonHugeist wrote: ↑05.02.2021, 06:25 Does it need one? Or it'll be optional? In my view the main advantage of a memtable that it is 100% functional without a connection and therefore can be used to de- and reconstruct data tables from any source.

No it does not "need" a connection. I just added it to inherit the ControlsCodepage and the Formatsettings from the connection component. That's all.

Brick08 any news on this?

Posted: **15.02.2021, 12:02**

EgonHugeist wrote: ↑12.02.2021, 05:53 Brick08 any news on this?

Now it's ok, thanks.

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