[Typo3] Clean up unused data in database

[Dirk]

>>>>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.

Seems so. It's a big issue IMHO.
And why are there fields/tables in the database that are not needed since the extension is not enabled with a clean install (e.g. tt_news, TV) ?

>Then it is not safe to delete some core tables, which starts with 'sys'.

The problem is:
- the table "static_taxes" does not begin with "sys_" (caused the Tools>DB Check:Record Statistics  problem)
- and neither table "static_taxes" nor the incorrectly removes field "lg_country_iso_2" starts with "sys_" (caused the error message in every FE page).

so it's not related to sys_ tables

>It is safe to delete tables for some default inactive plugins like 
>'tt_news' and 'indexed_search'.

maybe risky IMHO, having seen the effects of making a "full clean sweep" :-/

So long,
Dirk