My brain is warped by web development in general ;)
Thanks for your response. After I sent this , I got
an email from the PHP list, with a good chunk of code
to show how it's done. Yes, scripting is the only way
for this type of query.
Thank you for the response.
Stuart
--- [EMAIL PROTECTED] wrote:
> Hi Stuart,
>
> Getting your brains warped by logical statements,
> eh?
>
> If I remember correctly AND has precedence over OR.
> That means that the
> statement "A or B and C " evaluates to "A or (B and
> C) " which means that
> the statement will be true if A is true or if both B
> and C are true.
>
> Because of this precedence issue, you need to use
> parentheses to specify a
> new order of evaluation. This phrase, "(A or B) AND
> C" will be true only
> if either A or B is true at the same time that C is
> also true. That is a
> much different meaning than if the same statement
> were written without
> parentheses.
>
> Basically OR adds records to your results (less
> restrictive), AND takes
> them away (more restrictive).
>
> The easiest place to deal with the widely different
> request of your users
> is in your input processing script. Use your
> scripting language to build
> an appropriate query based on the options they
> provide. No single SQL
> statement will handle BOTH every combination of user
> input AND process
> quickly. You should build custom WHERE clauses
> based on your user's
> input. This is definitely NOT a one-size-fits-all
> situation.
>
> Remember to use parentheses. When in doubt, spell it
> out. Don't make the
> query engine read your mind.
>
> Shawn Green
> Database Administrator
> Unimin Corporation - Spruce Pine
>
>
> Stuart Felenstein <[EMAIL PROTECTED]> wrote on
> 09/22/2004 09:46:46 AM:
>
> > I'm back, trying to figure my way through a
> somewhat
> > confusing set of conditons.
> > Sort of doing a sanity check here.
> > First explanation:
> > I've put together a search (the database) form
> that
> > has 6 inputs.
> > Just to clarify, the fields are
> > 1-JobTitle
> > 2-City
> > 3-Start
> > 4-Industry
> > 5-State
> > 6-TaxTerm.
> >
> > The idea is that a user can choose one , two or
> all
> > fields to put criteria into. Regardless,
> whichever
> > one they choose , there should be a records
> return.
> > More criteria of course adds more refinement.
> >
> > Right now I only have 4 of the 6 fields rigged for
> > action- JobTitle, Start, Industry and State.
> > I half see what's going on, but unclear on how to
> set
> > it all up.
> > So right now, since Title and Start are divided by
> an
> > OR, if I chose both, then there is not refinement,
> I
> > get records that meet both criteria , not both
> > criteria combined , savvy ?
> > Industry is sort of seperate right now, and State
> can
> > be combined with industry to refine the results to
> > match up all industries within whatever particular
> > states.
> >
> > I guess ultimately I need a very long series of
> OR's
> > and AND's but not sure if there is something
> neater
> > and then operator precedence in a series of AND's
> and
> > OR's would probably throw me. At least I think
> so.
> >
> > ALright, so I"m sure this is one of my inance
> babbles
> > again, but if anyone can decipher my cry for
> > assistance, feedback, morsels of wisdom and
> knowledge,
> > I'm listening.
> >
> > Stuart
> > code:
> >
> > where JobTitle like '%{s_JobTitle}%'
> > or
> > PostStart >= DATE_SUB(CurDate(), Interval
> > ({s_PostStart}) day )
> > $VendorJobs->ds->SQL.= " OR (`VendorJobs`.Industry
> IN
> > (".$Projects."))";
> > $VendorJobs->ds->SQL.= " AND
> > (`VendorJobs`.LocationState IN (".$Projs."))";
> >
> > --
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> >
>
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