THE SHORT VERSION
-----------------

On non-Windows machines, you can execute the testing process
described below by running the following command in this directory:
	make check

This will run the TAP tests to run pg_upgrade, performing an upgrade
from the version in this source tree to a new instance of the same
version.

Testing an upgrade from a different version requires a dump to set up
the contents of this instance, with its set of binaries.  The following
variables are available to control the test (see DETAILS below about
the creation of the dump):
export olddump=...somewhere/dump.sql	(old version's dump)
export oldinstall=...otherversion/	(old version's install base path)

Finally, the tests can be done by running
	make check

DETAILS
-------

The most effective way to test pg_upgrade, aside from testing on user
data, is by upgrading the PostgreSQL regression database.

This testing process first requires the creation of a valid regression
database dump that can be then used for $olddump.  Such files contain
most database features and are specific to each major version of Postgres.

Here are the steps needed to create a dump file:

1)  Create and populate the regression database in the old cluster.
    This database can be created by running 'make installcheck' from
    src/test/regress using its source code tree.

2)  Use pg_dumpall to dump out the contents of the instance, including the
    regression database, in the shape of a SQL file.  This requires the *old*
    cluster's pg_dumpall so as the dump created is compatible with the
    version of the cluster it is dumped into.

Once the dump is created, it can be repeatedly used with $olddump and
`make check`, that automates the dump of the old database, its upgrade,
the dump out of the new database and the comparison of the dumps between
the old and new databases.  The contents of the dumps can also be manually
compared.