Subject Re: [IBO] IBOQuery.OnFilter: BLOB is always empty
Author Helen Borrie
At 03:03 PM 20/06/2005 +0200, you wrote:
>Hi Helen,
>Yes, for few cases I need a none trivial filter on BLOB.
>Of course I can encode the BLOB in another way, by coding some more
>complicated OnGetText and OnSetText events.
>But is there a simple way to know the BLOB in the OnFilter ? Or should I
>definitely forget about it ?

Forget about it. A blob isn't a string and the client can't see it. All
it can see at the OnFilterRecord point is the blob_id, which it will use to
fetch the blob contents *after* the record has been fetched, i.e. too late
for the OnFilterRecord event.

A much stronger strategy would be to parameterise the dataset and avoid
filtering altogether. If you need to do some complicated things with a
WHERE criterion, you can use InvalidateSQL and do the complicated stuff in
the OnPrepareSQL event, using WhereItems.