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Last tested: Oct 10, 2018
This is NOT a query timeout for when the query is actually executing.
What this is, is the amount of time, once a scheduled job is changed to executing, that it will wait to get a connection to the database, and if it can't get a connection to START the query, then it hits this timeout and fails out.
EXAMPLE: So imagine you have a connection pool of 5 set in the connection settings, and I kick off a dashboard with 5 queries that each take 20 minutes to run. Now say a schedule gets kicked off, because the connection pool is full, the query gets queued to get a connection, if it hits scheduler query timeout waiting to get one of those connections, it'll fail.