Lazarus

Programming => Databases => Topic started by: abilal on October 11, 2011, 04:09:59 pm

Title: Error on writing image to MDB via ODBC greather than 512 bytes
Post by: abilal on October 11, 2011, 04:09:59 pm

Hi Guys,

I am trying to Save an image (BMP) to MDB database via ODBC.
The good thing is that I can do it for images with file size less then 512 bytes.

When image size is greather than 512 bytes. I have ODBC Bind error (error screen is attached).

Any idea to fix the error?


my code is below:

procedure TForm1.ToDBClick(Sender: TObject);
var
 BinStream: TMemoryStream;
begin
  BinStream := TMemoryStream.Create;
  SQLQuery1.ReadOnly := false;
  SQLQuery1.SQL.Text := 'SELECT Pictures FROM Demo WHERE ID=1';
  SQLQuery1.Active   := True;
  SQLQuery1.Open;

   aImage.Picture.Bitmap.LoadFromFile('c:\temp\aaa.bmp');
   aImage.Refresh;
   aImage.Picture.Bitmap.SaveToStream(BinStream);
   BinStream.Position:=0;
 
   SQLQuery1.Edit;
   TBlobField(SQLQuery1.FieldByName('Pictures')).Clear;
   TBlobField(SQLQuery1.FieldByName('Pictures')).LoadFromStream(BinStream);
   //Caption:= IntToStr(BinStream.Size);
   SQLQuery1.Post;
   SQLQuery1.ApplyUpdates;
   SQLQuery1.Close;
   SQLQuery1.Active := False;
   BinStream.Free;
end;   

Title: Re: Error on writing image to MDB via ODBC greather than 512 bytes
Post by: LacaK on October 12, 2011, 07:31:52 am

Can you please post here some test application, which will show this error ?

Title: Re: Error on writing image to MDB via ODBC greather than 512 bytes
Post by: abilal on October 12, 2011, 09:10:18 am

I have attached a test project with test.MDB, test.bmp, test2.bmp files.

Note that, the test project works well done with 12x12pixel test2.bmp  ;)

Title: Re: Error on writing image to MDB via ODBC greather than 512 bytes
Post by: Lacak2 on October 12, 2011, 10:12:24 am

For me it works! also with test.bmp
Which version of FPC/Lazarus do you use (I use FPC 2.7.1 on Win98/XP ) ?
Can you test it with current snapshot ?
( ftp://ftp.freepascal.org/pub/lazarus/snapshots/ )

Title: Re: Error on writing image to MDB via ODBC greather than 512 bytes
Post by: abilal on October 12, 2011, 01:01:15 pm

Well, About Lazarus says:

Version #:0.9.30
Date: 2011-03-08
FPC Version: 2.4.2
SVN Revision: 29749
i386-win32-win32/win64

what is your ODBC verison?
and do you have an MS Office installation?

Title: Re: Error on writing image to MDB via ODBC greather than 512 bytes
Post by: Lacak2 on October 12, 2011, 02:13:25 pm

I suspect that your problem is related to FPC version, from time of FPC 2.4.2 there was some fixes to TODBCConnection.

ODBC version? - Default with Win98 or WinXP or Vista (I tested it on all 3 environments)
MS Office? - Yes

Title: Re: Error on writing image to MDB via ODBC greather than 512 bytes
Post by: abilal on October 12, 2011, 02:59:29 pm

Thank you very much for your interest ;)

Upgrade to FPC 2.7.1 fixes the problem :)
Now test-project works great for realy huge bmp files.

Problem Solved!

Cheers!