TLobLocator and security

[nicofari]

I have a table containing a blob, to which a
user should NOT have direct access.
We have an API access through a pl/sql package.
So there is an OracleDataset with an sql like:

begin
ILMaster.UtilsAccessOra.OpenStoricBlob(
:CurStoricBlob, :Id);
end;

The retrieve works fine.
The OracleDataset has an ApplyRecord procedure
in which we call another package function
to save the blob field
QryPutImage.SQL.Text :=

begin
IlMaster.utilsaccessora.putblob(aid => :aid,
ablob => :ablob,
agraphicclass => :agraphicclass);
end;

The Delphi code is like this:

With QryPutImage do
begin
SetVariable('aGraphicClass', OdsStoricoInt.FieldByName('DD_GRAPHIC_CLASS').AsString);
SetVariable('AId', OdsStoricoInt.FieldByName('NR_VALORE_INTERO').AsInteger);
SetComplexVariable('aBlob', Lob);
Execute;
(OdsStoricoInt.FieldByName('BL_STREAM') As TBlobField).SaveToStream(Lob);
end;

The problem is that this code works ONLY
if I grant the select/update on the table
to the invoker user..
The line with the SaveToStream(Lob) fails..
Does TLobLocator need select/update privileges
on the underlying field?
TIA
Bye
Nic

 

[Marco Kalter]

To resolve this you need to use a Temporary LOB (new in 4.0). This way you can write the data to the LOB before calling the stored procedure, which can subsequently write the data to the table.

------------------
Marco Kalter
Allround Automations

 

[nicofari]

I'll download the demo version of 4.00 and try,
thanks.
Only two questions
Do standard Lob Locator require select/update
grantees on the underlying column?
Are Temporary Lob a feature of version 9 only?

 

[Marco Kalter]

Do standard Lob Locator require select/update grantees on the underlying column?

Yes, because the application writes the data to the table instead of your stored pogram unit.

Are Temporary Lob a feature of version 9 only?

.
I forgot to mention this: it requires Oracle8i or later.

------------------
Marco Kalter
Allround Automations

 

[nicofari]

Thank you Marco.
I tried with 4.00 and I was able to use the
procedure without the grants