We didn't have any use of TransactionId as members of List, until
RelationSyncEntry->streamed_txns was introduced (464824323e57, pg14).
It's currently implemented as a list of int. This is not wrong at
present, but it may soon be, and I'm sure it rubs some people the wrong
way.
But is the rubbing way wrong enough to add support for TransactionId in
pg_list.h, including, say, T_XidList?
The minimal patch (attached) is quite small AFAICS.
--
Álvaro Herrera 48°01'N 7°57'E — https://www.EnterpriseDB.com/