On Wednesday 24 September 2008 2:12:18 pm Simone Dal Maso wrote:

Hi, I've a problem. I changed my server and I backup and restore my drupal site. The only problem I have is that new contents for anonymous users are not presented in homepage. If I login with the admin account I can see it normally. I disabled chaching of pages but the problem remains. Do you think that I should drop the cache tables? There are some tables llike cache, cacheviews etc, can I remove them without problems? thanks in advance.

Dropping a table means removing it from the system. Don't do that. Things will break. A lot. :-)

Under normal circumstances Drupal should be fairly smart about clearing the cache when it needs to. When restoring from a backup, however, you're not dealing with normal circumstances.

If you're on Drupal 6, then on the admin/settings/performance page is a big button that says "clear all caches". Put it to good use. If you're on Drupal 5, then the devel module provides a block with a link that will do that for you.

In either case, it should always be safe to TRUNCATE (not DROP) the cache tables, that is, any table that begins with "cache". The query "TRUNCATE cache" will delete all records in the cache table. That should always be safe to do to any cache table unless some module has done something incredibly stupid. One caveat, don't remove just part of the table this way. Some cache systems will only regenerate themselves if the entire table is empty, but will regenerate. So just go ahead and clear the whole table.