Question

OK, so I’ve found questions that cover how to do this with only two tables, tons of questions that explain how to do this if the ID does NOT exist in other tables, but not a solution to this query.

Basically, I have one table of wine vintages.

I then have four other tables that contain different types of content that is tied to a specific vintage (i.e. videos, blogs etc.)

I basically need to be able to pull a list of vintages that are in use i.e. where the vintage ID is used in one or more of the four content tables.

The closest I can get is this:

SELECT DISTINCT vintage_id FROM `pr_video_vintage`
INNER JOIN pr_video ON pr_video.fk_vintage_id = pr_video_vintage.vintage_id
INNER JOIN pr_reports ON pr_reports.fk_vintage_id = pr_video_vintage.vintage_id
INNER JOIN pr_reports_notes ON pr_reports_notes.fk_vintage_id = pr_video_vintage.vintage_id
INNER JOIN pr_blog_entries ON pr_blog_entries.fk_vintage_id = pr_video_vintage.vintage_id
ORDER BY `pr_video_vintage`.`vintage_id` ASC

But this (understandably I guess) only returns IDs that exist in ALL of the tables.

What I need is some form of ‘OR’ JOIN, but can’t find any information out about how to go about doing this.

tips? 🙂

Answer 1

Try this:

SELECT  distinct vintage_id FROM `pr_video_vintage`
where exists(select 1 from pr_video where pr_video.fk_vintage_id = pr_video_vintage.vintage_id)
   or exists(select 1 from pr_reports where pr_reports.fk_vintage_id = pr_video_vintage.vintage_id)
   or exists(select 1 from pr_reports_notes where pr_reports_notes.fk_vintage_id = pr_video_vintage.vintage_id)
   or exists(select 1 from pr_blog_entries where pr_blog_entries.fk_vintage_id = pr_video_vintage.vintage_id)

or

    SELECT  distinct vintage_id FROM `pr_video_vintage`
where pr_video_vintage.vintage_id in (select pr_video.fk_vintage_id from pr_video)
   or pr_video_vintage.vintage_id in (select pr_reports.fk_vintage_id from pr_reports)
   or pr_video_vintage.vintage_id in (select pr_reports_notes.fk_vintage_id from pr_reports_notes)
   or pr_video_vintage.vintage_id in (select pr_blog_entries.fk_vintage_id from pr_blog_entries)

or

SELECT  distinct vintage_id FROM `pr_video_vintage`
where pr_video_vintage.vintage_id in (
   select pr_video.fk_vintage_id from pr_video
   union
   select pr_reports.fk_vintage_id from pr_reports
   union
   select pr_reports_notes.fk_vintage_id from pr_reports_notes
   union
   select pr_blog_entries.fk_vintage_id from pr_blog_entries)