Shipment Methods DB manual

[Halo]

Previous manual update on shipping rate only require us to update 1 table.

In this 2.0.0 ver., you will need to update 2 tables namely:

jos_virtuemart_shipmentmethods_en_gb
jos_virtuemart_shipmentmethods

in 'jos_virtuemart_shipmentmethods_en_gb', there is 'slug' column, does it need to be unique and what function it serve?

FYI, i like to manually update my shipping methods through DB dump