[To hackers this time] At 12:11 27/10/00 +0900, Hiroshi Inoue wrote: > >For example,LIMIT ALL means LIMIT 1 for optimizer and means >no LIMIT for executor. >Comments ? > It seems there's two possibilities: (a) You know you will only use a limited number of rows, but you are not sure exactly how many. In this case, I'd vote for a 'OPTIMIZE FOR FAST START' clause. (b) You really want all rows, in which case you should let the optimizer do it's stuff. If it fails to work well, then use either 'OPTIMIZE FOR TOTAL COST' or 'OPTIMIZE FOR FAST START' to change the behaviour. ISTM that LIMIT ALL is just the syntax for the default limit clause - and should, if anything, be equivalent to 'OPTIMIZE FOR TOTAL COST'. ---------------------------------------------------------------- Philip Warner | __---_____ Albatross Consulting Pty. Ltd. |----/ - \ (A.B.N. 75 008 659 498) | /(@) ______---_ Tel: (+61) 0500 83 82 81 | _________ \ Fax: (+61) 0500 83 82 82 | ___________ | Http://www.rhyme.com.au | / \| | --________-- PGP key available upon request, | / and from pgp5.ai.mit.edu:11371 |/
