Assigning loot by level

[Havok2all]

I am wondering if there is a command similar to this:

update npc_types set loottable_id = X where id >= 202000 and id <= 202999;

That will add a specific loot table id to NPCs in a certain level range like lvl 1 - 5. I would like for it to add to the existing loot tables and not replace them.

Thanks for any help. Still new to working with dbs.