Re: Does Informix do Versioning Read-Only Transactions?

>>>>> "gb" == Graeme Burnett <rgb@xinit.demon.co.uk> writes: >> D. Erway (derway@ndc.com) wrote: >> >> : Does anyone know if any versions of Informix, (maybe the latest - 7), do >> : Versioning Consistency Control like Oracle 7 does? gb> From "Informix Guide to SQL 7.1 Tutorial" pp7-15 para 5: gb> "The definitions for ANSI Serializable, ANSI Repeatable Read, and gb> Informix Repeatable Read isolation levels are all the same. gb> The Repeatable Read isolation level asks the database server to put a gb> lock on every fow the program examines and fetches. the locks that are gb> placed are shareable for an ordinary cursor and promotable for an update gb> cursor. The locks are placed individually as each row is examinted. They gb> are not released util the cursor closes or a transaction ends." Sorry, I wasn't clear. The Oracle feature, (and Multi-versioning consistency control in general), allows a repeatable read snapshot of the whole database, without locking out writers! Don