Possibility to modify via SQL SalesUnit & PurChUnit & InventUnit

Hi Everybody

It's my first question in this Community :)

So my need is that I want to modify SalesUnit & PurchUnit & InventUnit using SQL.

Why this modification ? Because we setuped these units by Pack instead of Unit which is wrong.

We have already some Purchase Lines & Sales Lines (so inventory moved for these items).

So I saw that I have to modify this information in InventTableModule by putting the field UnitId to "U".

I have also to modify SalesLine (SalesUnit ==> "U"). For PurchLine, there is no change to make, because in the order we fill manually this field by "CS" (CASES).

My question : Is my approch good ? I have to modify only these tables ? Or I have to do it in an other way ?

Thanks.