Thread:Project:Support desk/Unusually Large database: 8GB/reply (3)

As detailed on Manual:Reduce size of the database, you can e.g. compress the contents of the text table and you can compress future revisions. You can also permanently delete archived revisions, which will in fact permanently remove those revisions, which are not visible to the public anyway.

Additionally, you could even remove the page histories - however, that would permanently remove all old revisions and their texts.

To refresh the searchindex (and a few other tables), you can run the maintenance script rebuildall.php. See Manual:Rebuildall.php! Additionally to having a smaller DB size, this might also be useful to get deleted pages removed from your search results.