Manually inserting categories

[Lamename]

Hello. I'm trying to import an entire database (a huge task!), and I would like to know which fields are "required" to import all my categories.

If I'm right, I should insert in the following fields:
t_virtuemart_categories
- virtuemart_category_id
- virtuemart_vendor_id
- cat_params (would like information on what this is, if possible)
- created_on
- created_by
- modified_on
- modified_by
- locked_on


t_virtuemart_categories_en_gb
- virtuemart_category_id
- category_name
- slug
- (description, key and title columns)


t_virtuemart_category_categories
- id
- category_parent_id (I guess if it's a root category, should be left at 0)
- category_child_id (left to self id if it's root category? what if it has multiple childs?
- ordering (is this the same as some kind of "display order"?)

Is that it? I was thinking about editing the tables and add foreign keys (to add on update cascade), would it be better to instead do it via PHP and insert onto their own individual rows instead?