Ronan,

At 08:48 PM 6/01/2004 +0100, you wrote:

>Hello,
>
>I am using a TIBOStoredProc to INSERT a blob into a table (Firebird 1.5 R7).
>An AV is thrown see code extract.
>
>procedure TDataModule2.waADD_PROJECTExecute(Sender: TObject);
>var
> a1: string;
>begin
> with IBO_SP_ADD_PROJECT, pWebApp do begin

To begin with, for an executable stored procedure (which this MUST be) you
don't need to burden yourself with the shortcomings of the VCL TBlobfield
and params. Use a TIB_DSQL for this operation. Make its SQL property to
be a parameterised call to your SP:

EXECUTE PROCEDURE SP_ADD_PROJECT(:param1, :param2, :blobparam, ...)

Write a method that writes any blob sub_type 0 column, using the superior
internal methods of TIB_BlobStream. Once you have the blob moving via the
stream, the rest just falls into place. Here's such a method (test for
existence of the file *before* passing it to the procedure and make sure
the owning statement is prepared before passing the tib_Column reference):

procedure MyDM.StreamThisBlob(aFileName: string; aColumn: TIB_ColumnBlob);
var
Instream: TFileStream;
begin
Instream := TFileStream.Create(aFileName, fmOpenRead);
try
if Instream.Assigned then
aColumn.Assign(TStream(Instream)); // not certain you need this casting
finally
Instream.Free;
end;
end;
.......................................
Invocation code:
...
var
a1: string;
begin
...
with MyDM.ib_dsql1 do
begin
if not Prepared then Prepare;
<assign your non-blob parameters>;
a1 := 'c:\a.gif';
if FileExists(a1) then
try
StreamThisBlob(a1, ParamByName('BlobParam'));
except
<call code to handle the exception>
end;
...
if not ParamByName('BlobParam').Assigned then
ParamByName('BlobParam').Clear; //ensures empty blob is null
...
<do any other assignments>
Execute;
end;
...
end;

The parameter assignment logic is only a suggestion, as I don't know what
you actually want to do if the file is missing or something goes wrong with
the blob-streaming (e.g. someone has the file open) or whatever.

Helen