Re: Undocummented: SET ISOLATION TO DIRTY READ

Andy Kent (akent@cix.compulink.co.uk) wrote: : > SET ISOLATION TO REPEATABLE READ will lock each fetched row in the : cursor. : In some versions the lock testing/ acquisition is done on every row : *touched* rather than every row fetched. So non-indexes searches can be : mighty expensive with Repeatable Read. : Can anyone tell me which version this is changed in? I didn't know it had changed. I thought it was true of all versions. : Also, I think I've sometimes seen OnLine (4.10) just not bother to lock : the rows but lock the table instead. Can anyone confirm/ deny this and if : it's true, under what circumstances does it occur? I *THINK* (ie I am not sure) it places a table lock if and only if the optimiser detects that it is doing a full table scan. Again, so far as I am aware, this is not version dependent. graeme -- Disclaimer: The author's opinions are his own, and not necessarily those of Pyramid Technology Ltd. or Pyramid Technology Inc. --------------------------------------------------------------------------- -m------- Graeme Sargent Voice: +44 (0)252 373035 ---mmm----- Senior Database Consultant Fax : +44 (0)252 373135 -----mmmmm--- Pyramid Technology Ltd. Telex: Tell who??? -------mmmmmmm- Farnborough, Hants GU14 7PL Email: graeme@pyra.co.uk --------------------------------------------------------------------------- We have the technology. The tricky bit is learning how to use it.