Simon Riggs wrote:
> ISTM that multitrans could be used here. Two xids, one xmax.
Hmm, yeah, this seems a reasonable suggestion. The problem is that we
don't have a mechanism today for saying "this Xid holds a shared lock,
this one holds an exclusive lock". So code-wise it wouldn't be simple
to do. It's a single bit per Xid, but I don't see where to store such a
thing.
I'm not sure we can use the simple "raise an ERROR" answer though,
because for users that would be a regression.
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