Re: yipeee!

Joe Weinstein wrote:

> Yep. Also, I really don't want to sound like I'm picking only on Oracle,
> because I complain about other DBMSes too. Oracle's TAF fooled a number
> of customers into believing it really was Transparent Application Failover,
> but it seems to be so only for certain mostly-idle clients. The reason I
> say this is because while there is no data loss during a failover, nor
> even any transactional context (locks), what is lost is any *computational*
> context that the client may be relying on if it was actually doing
> something when the failover occurred. For instance, most cursor context
> is lost. Java clients that may have created and are re-using Prepared
> Statements will find that all those prepared statements are now defunct,
> and must be recreated before the client can even retry what they were
> doing.
> This generally means returning to the line of code right after obtaining
> the
> original connection. Having the connection automatically failover to an
> appropriate backup DBMS is certainly valuable, but calling it "TAF" was
> 'aiming high' in the marketing department, IMHO.
> Joe

 From the client's standpoint it is completely transparent which is the origin of the name.

Perhaps you need to come take the class I teach on RAC.

-- 
Daniel Morgan
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