i need to free as more space as possible from the db, so i would like to delete entries on the following tables
fkwaexktcxl10n_cache with 11k entries
fkwaexktcxpage with 35k entries
fkwaexktcxrecentchanges with 70k entries
fkwaexktcxrevision with 70k entries
fkwaexktcxsearchindex with 35k entries
fkwaexktcxtext with 70k entries
fkwaexktcxexternallinks with 600+ Mb of space
Shouldn't the recentchanges table be filled with changes from the last 90 days and older changes should get removed. Obviously this removal is not happening in your case.
There is a maintenance script to rebuild the contents of the recentchanges table; this will make sure that old entries get removed.
The rebuildall.php script will also rebuild the contents of the externallinks table.
See Manual:$wgRCMaxAge to configure how long they should stay. Note that on each edit there is a 1% chance that the recent changes table will be purged.
I see no point in running the rebuildall.php script if it will generate the table with the same contents... A externallinks table so bloated probably means your wiki is filled with tons of spam pages. Have you ever looked who is editing your wiki? See also Manual:Combating spam although it may be too late now
