Cyril Godefroy wrote:
>
> Please excuse me if this is a bit off-topic, and point me to the right list.
>
> I'm using MySQL on a web site I'm creating, in conjuncyion with PHP. I love
> it. But it's my very first taste of SQL.
>
> One of the areas of the site is a query on ISP in France, and this is where
> I have a problem. I created my tables like that:
> Provider (ID, Name, Adress, Web, etc)
> Package (ID, ProviderID, Price, MonthlyTransfer, OS,...)
> Feature (ID, Name, Description)
> FeatureToPackage (FeatureID, PackageID)
>
> This way, I know which providers use PHP as a feature, or give Database
> Access, or Email aliases, etc. Unfortunately, despite my reading the
> documentation, tutorials, I'm still unable to find which providers use PHP
> AND databases AND SSL (for example).
>
> Got any tips or URLs to a good recipe? Is there a design error?
>
> Thanks in advance
> ==================================
> Cyril Godefroy
Hi Cyril
The design is O.K. but the query is a little bit tricky.
Try:
SELECT DISTINCT
Provider.*
FROM
Provider
, Package
, FeatureToPackage AS ftp1
, Feature AS f1
, FeatureToPackage AS ftp2
, Feature AS f2
, FeatureToPackage AS ftp3
, Feature AS f3
WHERE
Provider.ID=Package.ProviderID
AND Package.ID=ftp1.PackageID
AND ftp1.FeatureID=f1.ID
AND f1.Name='PHP'
AND Package.ID=ftp2.PackageID
AND ftp2.FeatureID=f2.ID
AND f2.Name='databases'
AND Package.ID=ftp3.PackageID
AND ftp3.FeatureID=f3.ID
AND f3.Name='SSL'
Tschau
Christian
