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Home -> Community -> Usenet -> c.d.o.server -> Re: Query Challenge
On Fri, 19 Mar 1999 19:01:52 -0000, "Peter Jones"
<pete_at_pkjones0.demon.co.uk> wrote:
>I've been taught that it's the order of the where clause that's important,
>i.e. the comparisons should be in reverse order of preference.
>
>If this is not the case, please let me know so that I can change my approach
>;-(
In my experiences Marc is absolutelly right. It's the order of the tables in the FROM clause that is important when RBO is used and nesteed loops are involved. The parser goes from the bottom up and from the right to left, so put the table that should be the driving table of the nesteed loop operation at the end of the list. The parser will get it first in the list and make it the driving table.
>Cheers
>Pete
HTH,
Jurij Modic <jmodic_at_src.si>
Certified Oracle7 DBA (OCP)
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