pg_migrator
-----------
Version 8.4.13


What it Does
------------
pg_migrator allows data stored in Postgres data files to be migrated to
a later Postgres major version without the dump/reload of data typically
required for major version upgrades, e.g. 8.3.7 -> 8.4.1. It is not
required for minor version upgrades, e.gz. 8.4.1 -> 8.4.5.


Supported Versions
------------------
pg_migrator supports upgrades from 8.3.X, 8.4.X, and 8.5.X, including
snapshot and alpha releases.    pg_migrator also allows upgrades from
EnterpriseDB's Postgres Plus Advanced Server 8.3 to 8.3R2.


Limitations In Migrating _to_ PostgreSQL 8.4 (but not 8.5)
----------------------------------------------------------
pg_migrator will not work if a user column is defined as:

	o  a user-defined composite data type
	o  a user-defined array data type
	o  a user-defined enum data type

You must drop any such columns and migrate them manually.


Limitations In Migrating _from_ PostgreSQL 8.3
----------------------------------------------
pg_migrator will not work for a migration from 8.3 if a user column
is defined as:

	o  a tsquery data type
	o  data type 'name' and is not the first column

You must drop any such columns and migrate them manually.

pg_migrator will require a table rebuild if:

	o  a user column is of data type tsvector

pg_migrator will require a reindex if:

	o  an index is of type hash or gin
	o  an index uses bpchar_pattern_ops

Also, the default datetime storage format changed to integer after Postgres
8.3.  pg_migrator will check that the datetime storage format used by
the old and new clusters match.

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.

All failure, rebuild, and reindex cases will be reported by pg_migrator
if they affect your installation;  post-migration scripts to rebuild
tables and indexes will be automatically generated.  


Installation
------------
See the INSTALL file for detailed installation instructions.  

For deployment testing, create a schema-only copy of the old cluster,
insert dummy data, and migrate that.  

If you want to use link mode and you don't want your old cluster to be
modified when the new cluster is started, make a copy of the old cluster
and migrate that with link mode.  To make a valid copy of the old
cluster, use 'rsync' to create a dirty copy of the old cluster while the
server is running, then shut down the old server and run rsync again to
update the copy with any changes to make it consistent.


Help
----
The pg_migrator web site is http://pgfoundry.org/projects/pg-migrator/.
To submit a bug report or get assistance, email 
pg-migrator-general@pgfoundry.org.  The most current pg_migrator release
is at http://pgfoundry.org/frs/?group_id=1000235.


Additional Files
----------------
CHANGES		release changes
DEVELOPERS	information for pg_migrator developers
IMPLEMENATION	implentation details
INSTALL		installation instructions
LICENSE		pg_migrator license
README		this file
TODO		TODO items
