Re: Rowid range in Informix 7.x

Michal Hajek <hajek@nspuh.cz> p''e v''l'nku <351A5F64.2F5F@nspuh.cz>? > David Kosenko wrote: > > > > Do note that if you are trying to use real rowids, and your table is fragmented, > > the rowids will NOT be guaranteed unique, and you CAN have multiple rows with > > the same rowid (albeit in different fragments). > > Excuse me, I seem not to understand well the term "fragmented > tables". Do you mean tables with more extents ? Or it is > something, which came with versions > 5.xx ?? Yes, you can distribute rows across dbspaces. Fragmented tables don't contain the hidden rowid column. You can use the WITH ROWIDS clause (in CREATE ST.) (or ADD ROWIDS in ALTER TABLE). But there is used an index to map the rowid to a physical location. This means that accessing data in a fragmented table by rowid isn't faster than accessing them using PK and is slower than in nonfragmented table! BTW only primary keys are defined in the ANSI specification of SQL... HTH, Pepa. > > This is important thing, we use programs, which use rowids > very often (OnLine 5.02). > > Thanks, > > Michal Hajek > > -- > -------------------------------------------------------------- > Michal Hajek mailto:hajek@nspuh.cz > Sprava NIS http://www.nspuh.cz > NsP Uherske Hradiste phone : voice +420 0632 529 204 > Purkynova 365 fax +420 0632 551 014 > 686 68 Uherske Hradiste Czech Republic > -------------------------------------------------------------- > *************************************************************************** Please remove the NOSPAM- from my address before replying. Josef Dufek ISS Czech, s. r. o. jdufek@iss.cz jdufek@post.cz ****************************************************************************