What happens here ?
Date: 9 Sep 1994 03:05:45 +0100 (GMT)
Message-ID: <521_at_marlene.GUN.de>
Hi, I have the following admittedly rather strange piece of embedded SQL (Rdb 6.0, C):
PSEUDOCODE:
open write transaction
declare statement x as "select * from xyz where x = 1000"
open cursor from statement x
delete from xyz where x = 1000
fetch cursor
while (found)
modify record
insert record
fetch cursor
end while
close transaction
Well, I can hear you say "What ?!". What the original piece of code really does is to renumerate some counter contained in the record. I have rewritten the whole thing so that all records ( that is the information neccessary) are fetched and after that updated. The thing which really bugs me is that at RDB 6.0 it will fetch exactly ONE record (even if more than one where x = 1000). I assume this is because an open cursor also fetches the first record internally. Now in an Oracle version of the same piece of code it will actually work (you see, it was first developed on Oracle). I assume this is because there were always less than, say, 30 rows matching the criteria and as far as I know Oracle has a bigger internal fetch buffer. However I do not think that it would work with large number of records. Is there a standard on this ? I believe either NO or ALL records should be found but not SOME... Oh yes, all of the above code is using dynamic SQL (SQLDA / SQLDA2).
Cheers from a confused RDB/Oracle user....
Andrew (renney_at_marlene.gun.de) Received on Fri Sep 09 1994 - 04:05:45 CEST