[Typo3] Clean up unused data in database

[tapio]

Dirk wrote:
>>>There are quite some tables I'm hesitant to delete; for example these:
>>>
>>>Removing tables (rename with prefix)
>>>	ALTER TABLE static_taxes RENAME zzz_deleted_static_taxes;	
>>>Records in table: 35	
>>>	ALTER TABLE sys_todos RENAME zzz_deleted_sys_todos;	
>>>Records in table: 1	
>>>	ALTER TABLE sys_todos_users_mm RENAME zzz_deleted_sys_todos_users_mm;	
>>>Records in table: 1	
>>>	ALTER TABLE sys_workflows RENAME zzz_deleted_sys_workflows;	

> yes, they were inactive, so that's okay
> (what's not okay see my other mail...)


It seems that the compare tools checks *only* against installed plugins.
Some core files might use them also. If this is the case, the result is 
incorrect.
Then it is not safe to delete some core tables, which starts with 'sys'.
It is safe to delete tables for some default inactive plugins like 
'tt_news' and 'indexed_search'.