Re: RS_EPHEMERAL vs RS_TEMPORARY

On 2020-02-25 08:30, Antonin Houska wrote:
> I'm trying to figure out what's specific about RS_EPHEMERAL and RS_TEMPORARY
> slot kinds. The following comment (see definition of the
> ReplicationSlotPersistency enumeration) tells when each kind is dropped

The general idea is that an "ephemeral" slot is a future persistent slot 
that is not completely initialized yet.  If there is a crash and you 
find an ephemeral slot, you can clean it up.  The name is perhaps a bit 
odd, you can think of it as an uninitialized one.  A temporary slot is 
one that behaves like a temporary table: It is removed at the end of a 
session.

Perhaps the implementation differences are not big or are none, but it's 
relevant for reporting.  For example, the pg_replication_slots view 
shows which slots are temporary.  You wouldn't want to show an ephemeral 
slot as temporary.

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
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