Well why even use a subquery?
SELECT adresse
FROM tblcourriel, tblcontactinfo, tblcontactcontactinfo, tblinscription, tblactivite
WHERE tblcourriel.id = tblcontactinfo.reference
AND tblcontactinto.type = 2
AND tblcontactinfo.id = tblcontactcontactinfo.contactinfo
AND tblcontactcontactinfo.contact = tblinscription.participant
AND tblinscription.activite = tblactivite.id
AND tblactivite.nom like '%g05%'
That should produce the same results, you may want to check its performance.
Mike Hillyer, Technical Writer
MySQL AB, www.mysql.com
Office: +1 403-380-6535
Blog:
http://www.openwin.org/mike
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