troubleshooting Question

Optimalisation of double LEFT JOIN MySQL query

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thijs321 asked on
6 Comments2 Solutions802 ViewsLast Modified:
I have 4 MySQL tables:

jobs (id, title, branchId)
contains jobs and the branch where they are part of

oldJobs (id, title, branchId)
same as jobs, except contains old jobs which are not open anymore

branches (id, name)
contains all branches

applies (id, jobId)
contains applies with their corresponding job id

Now I need to get the number of applies that were received per job and the corresponding branch.
If I only search for applies in the `jobs` table and forget about the `oldJobs`, then I use the query below.

How to change this query for including the `oldJobs`?

(The first that comes into my mind is to add another
LEFT JOIN for `oldJobs`, but then I don't know how to include to corresponding branch, because in the query below
the branch is LEFT JOINed on `jobs` and not `oldJobs`.)
				applies AS a
				jobs AS j
				a.jobId =
				branches AS b
			ON = j.branchId
Mark Wills
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