Fix DB migrations when DB is empty #611
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In elan-ev#602 a deadlock bug was fixed but it was not tested with an empty DB where locking the table obviously fails. This commit fixes that problem by just creating that table before anything else. It is an easy fix but I'm pretty sure it's correct. Consider all orderings of the two operations: A create if not exists A lock B create if not exists B lock ------------------------------------------------------ A create if not exists B create if not exists A lock B lock ------------------------------------------------------ A create if not exists B create if not exists B lock A lock Regardless of whether the DB is empty or already has __db_migrations, this never leads to a deadlock.
LukasKalbertodt
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JulianKniephoff
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Nov 30, 2022
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an empty DB where locking the table obviously fails. This fixes that problem by just creating that table before anything else. It is an easy fix but I'm pretty sure it's correct.
Consider all orderings of the two operations:
Regardless of whether the DB is empty or already has __db_migrations, this never leads to a deadlock.