Re: Database or store to handle 30 Mb/sec and 40,000 inserts/sec

Galen Boyer wrote:
> On 19 Feb 2006, galen_boyer_at_yahoo.com wrote:
>
>

>> When would you ever want to read uncommitted records? Uncommitted read is just fine for anything statistical. When mining a DSS or ODS system there is no need to get exact data. Whether someone returned a pair of shoes or not is irrelevant for trend analysis.
Does Oracle support query sampling? If so, there you go...

I find it highly amusing how posters justify isolation levels based on locking behavior.
Isolation is semantics, locking is implementation. There are quite viable solutions for READ COMMITTED isolation level which have the exactly same concurrency behavior as Oracle's implementation of Snapshot Isolation.
Declaring them worse or inadequate merely by virtue of not being the same is pretty intolerant.

I know a bit about Oracle's implementation of snapshot isolation. apparanetly there are posters here who believe they can compare it to what MS has delivered. None of them, so far, has justified their claims on lack of scalability (beyond "it's new", it can't be trusted).

Care to cough up some hard facts? Given that SQL Server 2000 is 6 years old and any Oracle product that age has been called "neolithic" by some posters in this group, it is much more interesting to compare the here and now that the history of any vendors perceived shortcoming.

So why is SQL Server 2005's implementation of Snapshot isolation bad?

Cheers
Serge

-- 
Serge Rielau
DB2 Solutions Development
IBM Toronto Lab