Hey folks,
I'm what I might call a "novice hack" at SQL in general, so forgive any blatant oversighs on my part.
My problem is this, I have three tables as such:
region
===========
region_id
region_name
region_no
contact
===========
contact_id
name_first
name_last
email
contact_join
============
contact_id
parent_id
parent_table
relationship
The contact_join table works by holding the name of the table the contact is for in the parent_table field, and the id of the record in that table.
A simple example of the three tables might be:
region:
23, 'South / Florida', '234'
contact:
11, 'John', 'Doe', 'generic@aol.com'
contact_join:
11, 23, 'region', 'Manager'
There are numerous tables that a record in the contact table might be connected to which is why I have the parent_table field. If there is a better way to do this, I'm all ears, but I'd rather my question were answerd since I dont want to rewrite the code I have already....which leads me to the question:
I want a view that will show all the relevant information about a region, namely the regino_name, region_no, c.name_first, c.name_last, c.email and cj.relationship (contact c, contact_join cj). I have come up with this query (I'm new at joins if you couldnt guess):
SELECT
r.region_name, r.region_no,
cj.relationship,
c.name_last,
c.name_first,
c.email
FROM
((region r
LEFT JOIN
contact_join cj
ON
((cj.parent_id = r.region_id)))
LEFT JOIN
contact c
ON
((c.id = cj.contact_id)))
WHERE
(cj.parent_table = 'region');
The problem is, sometimes no contact information has been entered yet, and I need to be able to see regions even if they have no contact information. The above query will only show items that have a contact_join entry with the parent_table as 'region'.
In pseudocode, I want this:
SELECT /* region data from region table, and if contact information exists for a region, select the contact information as well, otherwise leave the contact fields blank */
Follow? Let me know if this dosent make any sense.
Any help would be appriciated.
Regards
-Tom
---------------------------------
Tom von Schwerdtner
Webmaster, Facilities Plus Inc.
301-340-5101
---------------------------------
