As a reminder, COPY FREEZE still does not issue any warning/notice if
the freezing does not happen:
Requests copying the data with rows already frozen, just as they would be after running the <command>VACUUM
FREEZE</>command. This is intended as a performance option for initial data loading. Rows will be frozen only
ifthe table being loaded has been created in the current subtransaction, there are no cursors open and there
areno older snapshots held by this transaction. If those conditions are not met the command will continue without
errorthough will not freeze rows. It is also possible in rare cases that the request cannot be honoured for
internalreasons, hence <literal>FREEZE</literal> is more of a guideline than a hard rule.
Note that all other sessions will immediately be able to see the data once it has been successfully loaded.
Thisviolates the normal rules of MVCC visibility and by specifying this option the user acknowledges explicitly
thatthis is understood.
Didn't we want to issue the user some kind of feedback?
-- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB
http://enterprisedb.com
+ It's impossible for everything to be true. +