</para>

<para>

As a rule of thumb, <structfield>queryid</structfield> values can be assumed to be

stable and comparable only so long as the underlying server version and

catalog metadata details stay exactly the same. Two servers

participating in replication based on physical WAL replay can be expected

to have identical <structfield>queryid</structfield> values for the same query.

However, logical replication schemes do not promise to keep replicas

identical in all relevant details, so <structfield>queryid</structfield> will

not be a useful identifier for accumulating costs across a set of logical

replicas. If in doubt, direct testing is recommended.

Two servers participating in replication based on physical WAL replay can

be expected to have identical <structfield>queryid</structfield> values for

the same query. However, logical replication schemes do not promise to

keep replicas identical in all relevant details, so

<structfield>queryid</structfield> will not be a useful identifier for

accumulating costs across a set of logical replicas.

If in doubt, direct testing is recommended.

</para>

<para>

Generally, it can be assumed that <structfield>queryid</structfield> values

are stable between minor version releases of <productname>PostgreSQL</productname>,

providing that instances are running on the same machine architecture and

the catalog metadata details match. Compatibility will only be broken

between minor versions as a last resort.

</para>

<para>