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Advice needed Oracle 8i + Delphi 5.0: Invalid BLOB handle in record buffer

Hello,
I've such a problem. I try to access databace field (varchar4000). When I
try to read this field I have exeption "Invalid BLOB handle in record
buffer". I think that this exepction is generated by BDE because either for
Delphi and Oracle, this field is simple string field.
Does anybody know the solution for this problem?
Kind regards
Mateusz Sztaba
 

Re:Advice needed Oracle 8i + Delphi 5.0: Invalid BLOB handle in record buffer


1. Have you upgraded the BDE to the latest version (if you're using the
BDE)?
2. Is the TField.Datatype set to ftString?

also 4000 ? I know that up to oracle 7.3 2000 was the max length of a
varchar2 datatype. You could try making this a little sorter.

Colin.

Quote
"Matias" <mszt...@poczta.onet.pl> wrote in message

news:9pa4so$7v6$1@news.tpi.pl...
Quote
> Hello,
> I've such a problem. I try to access databace field (varchar4000). When I
> try to read this field I have exeption "Invalid BLOB handle in record
> buffer". I think that this exepction is generated by BDE because either
for
> Delphi and Oracle, this field is simple string field.
> Does anybody know the solution for this problem?
> Kind regards
> Mateusz Sztaba

Re:Advice needed Oracle 8i + Delphi 5.0: Invalid BLOB handle in record buffer


I just remembered another version of this problem.  If you're using a
dataset, scrolling forward, and then you go 'BACK' several records you'll
get this error.  This is because Delphi stores all the data from the record
set into a large buffer.  once the buffer is full it throws away the old
data.  If you then try to access that data, it's no longer available, and
hence you get the problem.  To solve that you'll need to alter your program
so that it never tries to load that much data into memory,  i.e. lookup the
blob field on the fly as a separate query, when you display that particular
row of the record set.

Colin.

Quote
"Colin Dawson" <colin.daw...@emis.co.uk> wrote in message

news:ts3hq1pv3ecnb0@corp.supernews.com...
Quote
> 1. Have you upgraded the BDE to the latest version (if you're using the
> BDE)?
> 2. Is the TField.Datatype set to ftString?

> also 4000 ? I know that up to oracle 7.3 2000 was the max length of a
> varchar2 datatype. You could try making this a little sorter.

> Colin.

> "Matias" <mszt...@poczta.onet.pl> wrote in message
> news:9pa4so$7v6$1@news.tpi.pl...
> > Hello,
> > I've such a problem. I try to access databace field (varchar4000). When
I
> > try to read this field I have exeption "Invalid BLOB handle in record
> > buffer". I think that this exepction is generated by BDE because either
> for
> > Delphi and Oracle, this field is simple string field.
> > Does anybody know the solution for this problem?
> > Kind regards
> > Mateusz Sztaba

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