Re: Left Join is producing duplicate results - MySQL & relational tables

Sorry Ken, I'm trying to learn a few too many things at once. Switching it around eliminated the error message but not the duplication. I'm eliminating as much of the code as I can to see that it isn't coming from PHP. Thanks again for your help. Mike Ken wrote:

In general, you should always be reading the manual first. From the SELECT syntax at http://www.mysql.com/doc/S/E/SELECT.html GROUP BY must be indicated before ORDER BY. So reverse the order of those portions. - Ken At 10:35 PM 7/11/01 -0400, Mike Gifford wrote:

It looked good, but it gave me an error.. Sorry ... WLPcountry.countryID ORDER BY WLPbib.title GROUP BY WLPbib.bibID MySQL Error: 1064 (You have an error in your SQL syntax near 'GROUP BY WLPbib.bibID ' at line 10) Please contact the webmaster and report the exact error message. Session halted. Ken wrote:

Mike - I'm not certain but it sounds like you might be looking for "GROUP BY". Do GROUP BY and then the columns that are identical in your results. - Ken At 09:46 PM 7/11/01 -0400, Mike Gifford wrote:

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 -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, e-mail: php-db-unsubscribe@lists.php.net For additional commands, e-mail: php-db-help@lists.php.net To contact the list administrators, e-mail: php-list-admin@lists.php.net

-- 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