What about...
SELECT WLPbib.bibID,
WLPbib.title,
WLPbib.publisher,
WLPbib.publicationDate,
WLPaddress.city,
WLPaddress.state,
WLPprofile.firstName,
WLPprofile.lastName,
WLPprofile.organization,
WLPcountry.languageName
FROM WLPprofile, WLPaddress, WLPcountry
WHERE WLPprofile.profileID = WLPbib.profileID
AND WLPaddress.publisherID = WLPbib.publisherID
AND WLPcountry.countryID = WLPaddress.countryID;
I had a similar problems with a database I was working with... It had a
main table with 29,000 listings, and I decided to normalize it to
improve query times (split the records into diff. tables, one for each
attribute of the record, associate the records back together by a common
ID than spanned all the tables)... I ended up with an SQL query that
spanned like 10 tables-- but it was -way- faster than one big table.
There's an excellent article on Normalization on PHPbuilder --
http://www.phpbuilder.com/columns/barry20000731.php3
If your WLP tables are very large, you may want to try using mySQL's
EXPLAIN SELECT [rest of select query]... function to figure out the best
(read: efficient) ways of performing this query... Indexes are
definitely a must if you are dealing with a lot of rows... If not, you
should be just fine with the above query-- which I -think- is
equivilent...
I don't have a ton of experience with SQL, so perhaps someone can better
elaborate.
Best of luck!
-----Original Message-----
From: Dobromir Velev [mailto:[EMAIL PROTECTED]]
Sent: Thursday, July 12, 2001 3:01 AM
To: [EMAIL PROTECTED]; Mike Gifford
Subject: Re: [PHP-DB] Left Join is producing duplicate results - MySQL &
relational tables
Hi,
Did you try to use something like this.
mysql_query("SELECT DISTINCT
WLPbib.bibID,
WLPbib.title,
WLPbib.publisher,
WLPbib.publicationDate,
WLPaddress.city,
WLPaddress.state,
WLPprofile.firstName,
WLPprofile.lastName,
WLPprofile.organization,
WLPcountry.languageName
FROM ((WLPbib
LEFT JOIN WLPprofile ON WLPprofile.profileID =
WLPbib.profileID)
LEFT JOIN WLPaddress ON WLPaddress.publisherID =
WLPbib.publisherID)
LEFT JOIN WLPcountry ON WLPcountry.countryID =
WLPaddress.countryID");
The other thing that may help is to rearange the order of the tables in
the FROM clause. Please check if some of the joins return more than one
result - if you have more than one address for a publisher the query
will return one row for every address.
Hope this helps
Dobromir Velev
-----Original Message-----
From: Mike Gifford <[EMAIL PROTECTED]>
To: [EMAIL PROTECTED] <[EMAIL PROTECTED]>
Date: Thursday, July 12, 2001 4:31 AM
Subject: [PHP-DB] Left Join is producing duplicate results - MySQL &
relational tables
>Hello,
>
>I posted this to the general list this morning & got a couple of good
leads, but
>they weren't able to actually fix the problem, so I'm posting here to
>the
db list.
>
>I'm making some headway on joining three MySQL tables.
>
>However, when I run this query:
>
>mysql_query("SELECT
> WLPbib.bibID,
> WLPbib.title,
> WLPbib.publisher,
> WLPbib.publicationDate,
> WLPaddress.city,
> WLPaddress.state,
> WLPprofile.firstName,
> WLPprofile.lastName,
> WLPprofile.organization,
> WLPcountry.languageName
> FROM WLPbib
> LEFT JOIN WLPprofile ON WLPprofile.profileID =
WLPbib.profileID
> LEFT JOIN WLPaddress ON WLPaddress.publisherID =
WLPbib.publisherID
> LEFT JOIN WLPcountry ON WLPcountry.countryID =
WLPaddress.countryID");
>
>I now get results in triplicate. ie. I'm getting three copies of the
>same title, firstName, organization, etc....
>
>I somehow suspected that this should be the result with LEFT JOIN, but
>I'm
not
>sure how to return a query without duplication.
>
>This is far better than what I had this morning (which was no response
>from
the
>server).
>
>Thanks. I'm new to joining tables...
>
>Someone wrote back suggesting that SELECT DISTINCT could be used to to
>the
job.
>
>Another person suggested that using UNIQUE(profileID) would make it
>look
nicer.
> I wasn't sure how to use UNIQUE with the last JOIN as it isn't
> directly
linked
>to WLPbib..
>
>Any suggestions would be useful.
>
>Mike
>
>--
>Mike Gifford, OpenConcept Consulting, http://openconcept.ca Offering
>everything your organization needs for an effective web site. Abolish
>Nuclear Weapons Now!: http://pgs.ca/petition/ It is a miracle that
>curiosity survives formal education. - A Einstein
>
>
>--
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>
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