Re: Help with a double left join

On Wed, 20 Jun 2001, Ari Nepon wrote:

> I am trying to do a left join FROM [a table with two columns that have
> foreign IDs] LEFT JOIN [two other tables, each has a unique ID].
> 
> I have the left join working where I join only two tables (not three):
> <!--current SQL-->
> SELECT track.ID, track.employee, track.client, track.task,
> track.description, track.hours_used, track.f_date, project.project_name
> FROM track LEFT JOIN project ON track.project=project.project_id
> WHERE track.client LIKE '%MMColParam%'
> <!--end-->
> 
> the two tables are track and project. Track is the left of the left join. It
> holds the foreign keys. project (and later clients) are the columns with the
> keys. I need to also left join clients ON track.client=client.ID.  Would
> someone tell me how the SQL statement should be that allows me to do the two
> left joins? Would it be:
> <!--wishful thinking SQL-->
> SELECT track.ID, track.employee, track.task, track.description,
> track.hours_used, track.f_date, project.project_name, clients.name
> FROM track LEFT JOIN project ON track.project=project.project_id AND LEFT
remove the 'AND'

FROM track LEFT JOIN project ON track.project=project.project_id LEFT

> JOIN client ON track.client=clients.ID
> WHERE track.client LIKE '%MMColParam%'
> <!--end-->
> 
> 
> '%MMColParam%' is just a variable used to hold a querystring variable in
> case anyone was wondering.
> 
> Thanks,
> 
> Ari
> 
> (database is MS access. language is ASP. Whole thing will eventually be
> redone in PostgreSQL and PHP, just as soon as I learn them:)
> ~~~~~~~~~~~~~~~~~~~~~~~~~
> Ari Nepon
> MRB Communications
> 4520 Wilde Street, Ste. 2
> Philadelphia, PA 19127
> p: 215.508.4920
> f: 215.508.4590
> http://www.mrbcomm.com
> 
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