To migrate to a new phpwiki installation you might want to backup your old pages 
(best via a zip dump), configure your new installation, and restore the old 
pages in PhpWikiAdministration. 
UPGRADING from 1.3.7 on requires just ?action=upgrade.

Can't unpack bad cached markup. Probably php_zlib extension not loaded.
=======================================================================
Sign in as ADMIN_USER, go to PhpWikiAdministration#Purge_Markup_Cache
and click on the [Purge Cache] button.

?action=upgrade
===============
To upgrade default pages, the database and some config settings 
add "?action=upgrade" to your HomePage url and press "Enter", which will
do most of the upgrades automatically.

You might need to enter the DBADMIN_USER and DBADMIN_PASSWD in 
config/config.ini for SQL databases and default permissions.

The importer looks at the Date header of the page. In your current wikidb 
against the creation date of the pgsrc, you want to import.
If you changed your pages after I changed the pgsrc pages, 
they will not be upgraded.

Or just upgrade your configuration as described below.

UPGRADING since 1.3.11
======================
?action=upgrade should be enough.

UPGRADING since 1.3.10
======================
?action=upgrade should be enough.

UPGRADING from 1.3.9
======================
At first you have to manually create a config/config.ini based on 
config-dist.ini and your previous index.php. We don't have a script,
to do that automatically.

mysql:
  ALTER TABLE page CHANGE id id INT NOT NULL AUTO_INCREMENT;
NOTE: ?action=upgrade does this also, if your mysql user has the 
ALTER permissions or DBADMIN_USER and DBADMIN_PASSWD are set.

UPGRADING from 1.3.7
======================
mysql + postgres:
  ALTER TABLE session ADD sess_ip CHAR(15) NOT NULL;
  CREATE INDEX sess_date ON session (sess_date); 

postgres:
  New pref and session tables have been added for more 
  efficiency.

user and themes:

WikiUser and signin.tmpl changed from $user->getId() to 
$user->getAuthenticatedId()
Authenticated reflects the level (confirmed by password), 
Signed just the username (possibly by cookie only)

pgsrc:

To upgrade not-existing pages add "?action=upgrade" to 
your HomePage url and press "Enter", which will
add all fresh pages from pgsrc to your pageset.
If you deleted some pages on purpose, you'll have to removed 
them again with PhpWikiAdministration/Remove then.

There's no smart "Merge Diffs" yet to upgrade existing docs,
this will come with the next release. Also upgrading the
database automatically.

UPGRADING from 1.2.x
======================
FIXME: WARNING WARNING: The schemas used by the new databases
are completely incompatible with schemas in any previous version
(i.e. before release 1.3.1 of PhpWiki).  If you install this new
PhpWiki, you must start with a new empty database (currently
either mysql, postgres or dba).  (It will be filled with the
usual default pages.)

FIXME: add more.

Here's an excerpt from a note I posted on phpwiki-talk with my 
recommendation on how to move a wiki from and older version of 
PhpWiki to a 1.3.x PhpWiki:

From: Jeff Dairiki <dairiki@dairiki.org>
Cc: phpwiki-talk@lists.sourceforge.net
Date: Fri, 9 Nov 2001 11:33:18 -0800

> Now, say I want to migrate all my 1.2.1 pages. I need to do a zip dump 
> (does the admin page let me do that?) and then.... what?
 
It's still a bit of a messy process at this point.  Here's my suggestion.

1. Start 1.3.x with an empty database.  Browse the FrontPage.  This should
fill the wiki with the distributed default 1.3.x pgsrc.  (You've probably
already gotten this far.)

2. Make a zip dump of your 1.2 wiki.  If the contents of
PhpWikiAdministration are correct there should be a links 
(near the top) which will do that for you.  You need to be
in admin mode, though.  This means you must have set an
admin user and passwd in admin.php, and you should be browsing
through a URL like:
  http://path.to.your/wiki/admin.php?PhpWikiAdministration
(If your PhpWikAdministration page is broken, then
  http://path.to.your/wiki/admin.php?zip=all
should get you a zip dump.)

WARNING! WARNING! WARNING!  There is a bug in releases 1.2.0
and 1.2.1 of PhpWiki which results in corrupt zip dumps if
you are using the DBA, DBM or flat-file backends.  If you
are using one of those backends you should make sure to
fix that bug (see note below) before making the zip dump.


3. Now upload your zip dump to your new 1.3 wiki.  (First you need to
have set the admin user/passwd in the new index.php.)  You should
be able to use the "Upload File" form on the PhpWikiAdministration
page.


If that works, the pages from your 1.2 wiki have now overwritten
the 1.3 pages (though the 1.3 pages are still saved in the archive).
This will break a bunch of 1.3 functionality until you restore
the page contents.  Of the top of my head, some pages for which 
this will be an issue are:
  MostPopular, RecentChanges, PhpWikiAdministration,
  MagicPhpWikiURLs, and ReleaseNotes.

To restore these pages to the original (1.3) contents:

4a. Login as the administration user (using the SignIn button at the
bottom right corner of the page.)  (You need to do this because
some of the pages which need fixing are locked.)

4b. Browse to a page which needs restoring.  Hit the "History" button
(at the bottom of the page).  This should get you a list of all
archived versions of the page.

4c. Browse to the archive 1.3 version of the page (probably version 
number 1) by clicking on the version number of the desired version.

4d. Click the "Edit old revision" button (bottom of page).  This should
get you to the edit form.

4e. Click the "Save" button.  This should save the archived page contents
as the current contents.

We really need to figure out a way to simplify this process, but, for now,
that's what you gotta do.

An older note on the same subject can be found at:
  http://sourceforge.net/forum/message.php?msg_id=107858
