Andres Freund <andres@2ndquadrant.com> writes:
> On 2013-05-13 14:35:47 -0400, Tom Lane wrote:
>> That is, in fact, exactly what we want to do and must do during initdb.
>> If you change anything about this code you'll break the way the
>> post-bootstrap initdb steps assign OIDs.
> Well, then we should use some other way to discern from those both
> cases. If you currently execute CREATE TABLE or something else in
> --single user mode the database cannot safely be pg_upgraded anymore
> since the oids might already be used in a freshly initdb'ed cluster in
> the new version.
[ shrug... ] In the list of ways you can break your system in --single
mode, that one has got to be exceedingly far down the list.
> DROPing and recreating a new index in --single mode isn't that
> uncommon...
Surely you'd just REINDEX it instead. Moreover, if it isn't a system
index already, why are you doing this in --single mode at all?
regards, tom lane