Hi all.


I have a case which I can't figure out, and it's really hurting me right
now. I have an app with about 50 reports, using FastReports. Just a few days
ago I noticed that two of my reports are throwing "Cannot prepare a blank
statement" error, which seems to come from IBO. As far as I know, I haven't
changed anything in those reports in ages, and I checked an older compiled
version of the app and it worked just fine.

Here's where it gets weird: I set two queries (of TIBOQuery type) at
runtime. There's a fairly simple SQL in one of them, and a bit more complex
but nothing strange in the second one, just a few joins. If I do something
like this after opening the queries:

while not HeaderQuery.Eof do
begin
ShowMessage(HeaderQuery.Fields[0].AsString);
HeaderQuery.Next;
end;

...it works ok, I can go through all records without any trouble. But, as
soon as the report opens, it throws the error mentioned above.

Now, the report may be a culprit here, but I'm dumbfounded as to how to
start searching for the cause here. The IBO source is way too complex for me
to wrap my mind around, so I'm posting this here (as well as in the
FastReport newsgroups) in hopes that someone could at least point me towards
the solution. Like, in which exact case would that error get thrown usually?

Any help greatly appreciated,
Antti Kurenniemi