Sam b3920e05e7
PERF: avoid table scan while performing a very large update (#24525)
We were seeing lots of deadlocks deploying this migration. This improves
the situation in 2 ways.

1. ddl transaction is avoided, so we hold locks for far shorter times
2. we operate in chunks of a maximum of 100_000 posts (though it is heavily filtered down)

* improve code so it is clearer
2023-11-23 18:15:40 +11:00
..