Re: oracle - mysql comparison

In article <cZ%Jc.94793$a24.93839_at_attbi_s03>,  "Jim Kennedy" <kennedy-downwithspammersfamily_at_attbi.net> wrote:

> "Daniel Morgan" <damorgan_at_x.washington.edu> wrote in message
> news:1090027361.387590_at_yasure...
> >
> >
> > michael newport wrote:
> >
> > > Jon,
> > >
> > > check out www.ca.com for Ingres, its the same strength as Oracle but
> > > will shortly be OpenSource.
> > >
> > > Regards
> > > Michael Newport
> >
> > And by 'strength' you mean?
> >
> > Daniel Morgan
> >
> I think he means it is good at locking. It has a strong locking mechanism.
> Last time I used Ingress (quite a few years ago) an insert into a table
> would lock the whole table! Why? It had page level locks and inserting a
> record into a table with a primary key locks the entire index which means
> only 1 person at a time could insert records. You had to commit to release
> the locks. So don't have long running transactions. Leads to bad
> programming practices; developers putting the system into autocommit mode.
> (yeach)

It was never true in Ingres that an insert locked the entire index (unless the optimizer decided to take out an initial table level lock, and that would only happen for unqualified updates.) What Jim may have run into is lock contention on the last leaf of a btree index with a sequential key, which would in effect serialize the inserts. For some time now, Ingres has had row level locking available. Of course one could avoid sequential keys, which have other potential performance problems (eg I/O hot spots).

I have to say I'm skeptical of how much experience Mr Kennedy might have had with Ingres if he can't spell it properly.

Karl Received on Sat Jul 17 2004 - 11:04:03 CDT