Promotable lock types

Posted in 1994

"Andy Kent" — Sat, 14 May 1994 09:53:41 GMT — source: Informix-list mailing list archive (1991-1998)

Can anyone explain how OnLine ensures that it will be able to promote an Update lock to Exclusive? I know the lock types HDR+S, IX and SIX are involved - how do these differ and what purpose does each of them serve? What are the circumstances under which OnLine would fail to promote a lock? Second question. I noticed the other day that a fetch with Repeatable Read will fail if it finds a U or X lock, whereas Committed Read and Cursor Stability only fail on an X lock. What is the thinking behind this? I'm currently working on an OnLine 4.10 site (yes I know...) Thanks very much. -Andy- akent@cix.compulink.co.uk (Andy Kent) ------------------------------------- 44 272 742815