On Mon, May 24, 2010 at 11:35 PM, Bruce Momjian <br...@momjian.us> wrote: > Have you read the docs? It does mention the issue with /contrib and > stuff. How do I document a limitation I don't know about? This is all > very vague. Please suggest some wording.
OK, here's an attempt. Please fact-check. -- General Limitations pg_upgrade relies on binary compatibility between the old and new on-disk formats, including the on-disk formats of individual data types. pg_upgrade attempts to detect cases in which the on-disk format has changed; for example, it verifies that the old and new clusters have the same value for --enable-integer-datetimes. However, there is no systematic way for pg_upgrade to detect problems of this type; it has hard-coded knowledge of the specific cases known to exist in core PostgreSQL, including /contrib. If third-party or user-defined data types or access methods are used, it is the user's responsibility to verify that the versions loaded into the old and new clusters use compatible on-disk formats. If they do not, pg_upgrade may appear to work but subsequently crash or silently corrupt data. pg_upgrade also relies on ABI compatibility between modules loaded into the old and new clusters. For example, if an SQL function in the old cluster is defined to call a particular C function, pg_upgrade will recreate SQL function in the new cluster and will configure it to call the same C function. If no such C function can be found by the new cluster, pg_upgrade will simply fail. However, if a C function of the same name exists in the new cluster, but expects a different number of arguments or different types of arguments, then it is likely to crash the system when called. In the worst case, data corruption could result. -- Also, the following sentence appears not to fit with our "only to 9.0" policy: "For Windows users, note that due to different integer datetimes settings used by the one-click installer and the MSI installer, it is only possible to upgrade from version 8.3 of the one-click distribution to version 8.4 of the one-click distribution. It is not possible to upgrade from the MSI installer to the one-click installer." -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise Postgres Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
