>>Executing the next statement gives me SQL error -902 Internal error.
> >>
> >>UPDATE MyTable
> >>SET MemoField = :MemoField
> >>WHERE (UniqueField = :Old$UniqueField) AND (MemoField = :Old$MemoField)
> >>
> > Is not supported by firebird. You can't put a blob field in "where".
> > ...
> You could try (MemoField containing :Old$MemoField) if this is specific

eno=

> ugh.

Thanks for the suggestion.
But it is not specific (waterproof) enough for me.
I'm working with short transactions, and i want to be sure no other user
changed the blob field in the meantime. My UPDATE statement has to return
exactly one effected row.

BTW is it possible to make the error message more specific, f.e. "Blob field
not allowed in WHERE clause"?

Bye
Robert
.-.