At the start of a repo update, it will create a copy of the apk table.
Throughout the update, it will query the original apk table for info.
All inserts and updates happen to the temp table. After the repo has been
verified as trusted, the original apk table is emptied, and all apks are
copied from the temp table to the real one.
I realise that the work done to query the apk table for info during the update
could happen against the temp table, but it was not neccesary to move all of
the queries that are required for this task to the temp apk provider.
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