Question Optimizing Kunena database tables

I have discovered that, when I try to optimize Kunena database tables with phpMyAdmin it is not possible and I get the advice to create a new table from the old one and then check it with analyze in phpMyAdmin. The reason I want to do this is that I have deleted about 30 % of mine forumposts.

I found this page with suggestions on how to do it:
www.geeksengine.com/database/manage-table/create-table-as.php

create table products_bk
as
select * from products
(naturally the table names are different than above for kunena)

This diminish my kunena_messages table with at least 50 % in size.
I guess after creating a new table I have to change name of both the old and new table.

I have looked for advice about this, but not found any, so I am grateful for input here.

You don't need to optimize the database. If you delete forum posts, it removes also the related rows in the database. But you must delete the messages permanently.

Why have a gotten a dozen notifications? This is not even my post!

I'm sorry, it was a error at the mail delivery for subscribers. Therefore you also got the mails.

I tried to optimize the kunena_messages table and it shrinked from 120 MB to 50 MB, but it did not work because when I posted I got: Kunena Internal Error: Please contact site administrator to fix this issue! so I had to revert to the original table. Don't try that.

I have digged deeper in this. kunena_messages table have an index with 12 keys and when I created the table it lacked index and thus got smaller but unfunctional. So it is no idea to create table because you have to create index, which will take a lot of space and you will gain almost nothing. kunena_messages_text dont have a big index, so it does not shrink in size.