[Mediawiki-l] unable to recover a mediawiki database

[Frames Project]

Hello

I already posted this problem and got no answer.
I also send this mail to MySql as I do not know if MediaWiki or MySql is a the 
origin of the problem.

Here is the description of what happened :

I am using MySql to store two MediaWiki databases named dftdb and framesdb
I am using MySql 4.1.20
I am using MediaWiki 1.9.3
I am using Scientific Linux 4.4

Each week I backup the directory /var/lib/mysql
On Wednesday I lost the /var partition, the mysql version,
the apache and php5, MediaWiki was the only one to stay alive.


I reinstalled the same versions of mysql, apache, php5 that were
running before the crash.

I copy the the saved /var/lib/mysql directory

A third old wiki running under Mediawiki 1.3 was correctly recovered
but, the new two new Wikis running under MediaWiki 1.9.3 I give the following
message :


  MediaWiki internal error.

Original exception: exception 'DBQueryError' with message 'A database error has
occurred
Query: SELECT value,exptime FROM `dft_objectcache` WHERE
keyname='dftdb-dft_:messages-hash'
Function: MediaWikiBagOStuff::_doquery
Error: 1016 Can't open file: 'dft_objectcache.ibd' (errno: 1) (localhost)
' in /home/dft/public_html/mediawiki/includes/Database.php:708


under phpMyAdmin these databases have no Type defined for the 33 tables
excepted 3 which have MyiSAM type.
The Collation column give "in use".

If somebody could tell me what hapenned ?
How a running database could become unreadable after reinstalling Mediawiki.
Is it possible that this were connected with the InnoDb type which is
the default used by phpMyAdmin at database creation ?

Thanks

Francois Colonna