Re: Arghh! Please Help.

OK, so my question to all of you is: Why do you prefer Nested Loop Joins? Isn't this begging things to go slow??? I can refer to Informix training where NLJ's are strongly discouraged. I'd say set the OPTCOMPIND=2, and NEVER go for nested loop joins. If there is some magical reason for using NLJ's I'd really like to know. Thanks, Tim > # OPTCOMPIND > # 0 => Nested loop joins will be preferred (where > # possible) over sortmerge joins and hash joins. > # 1 => If the transaction isolation mode is not > # "repeatable read", optimizer behaves as in (2) > # below. Otherwise it behaves as in (0) above. > # 2 => Use costs regardless of the transaction isolation > # mode. Nested loop joins are not necessarily > # preferred. Optimizer bases its decision purely > # on costs. > OPTCOMPIND 0 # To hint the optimizer> -- - -- --- Tim Schaefer ---- tschaefe@mindspring.com --- http://www.inxutil.com -- -

Tim Schaefer (tschaefe@mindspring.com) wrote: : Why do you prefer Nested Loop Joins? The only reason I can think of is that NLJ's get the first row back quickly. Other than that, I tend to agree with you. KR Pb