Re: Where can I get a complete list of all SQL Hints?

tonym101_at_hotmail.com (TM) wrote in message news:<7b718442.0306190949.7429abf3_at_posting.google.com>...

>
> It's a database configuration parameter.
>

No. It's a session configuration parameter. If it was a database config parameter, it would apply to everything. It can however be defaulted.

> > DB2's optimizer is neither smarter nor dumber, but more rigid in its
> > behavior and more abstract.
>
> ...and neither this nor that, rarely but often, perhaps or perhaps not
> I guess you mean?

Precisely.

>
> > But which level's best? God knows.
>
> Default level 5 is generally fine and good for mixed load
> environments. I'd recommend 7 for DSS-only environments running very
> complex ad-hoc queries. If you are doing OLTP only then lower levels
> may save a little time. This is all in the documentation.

So, what happens in a mixed environment?

> You choose
> an appropriate value and then forget about it... people don't go
> changing optimization level from query to query in practice.
>

Really? So that stuff about:
FOR READ or FETCH ONLY,
FOR UPDATE
OPTIMIZE FOR n ROWS
FETCH FIRST n ROWS ONLY

is for what? Ad-hoc queries?

Jeez...

Cheers
Nuno Souto
wizofoz2k_at_yahoo.com.au.nospam Received on Thu Jun 19 2003 - 21:29:10 CDT