By using a mod for your changes, it make it easier for you to manage your edits, and avoid any issue with base DB files. That's for this reason we recommend you to make it as mod, for not overwritting base files. It will avoid you to loose them when you upgrade your server too.
The main topic.
Well, modding is simple : Overwritting loaded files by the one you added to your mod without editing the default one located in ServerDir/db/.
For now, not everything can be "modded", only these things can : Items,Bots loadouts,Hideout files,Assorts,Traders,Weather,locales,scripting,maps,.
Create your mod folder, the name need to match like this : author-name-Version depending on what you put in the server.config.json.
In this mod folder, create a file called mod.config.json and put the following code in :
Note that you now have 3 main "folders". src,res,db:
src is made for adding scripts mods to the game, everything that is in /src/ folder. res is made for adding or editing games images (traders images for exemple), everything that is in /res/ folder. db is made for edit or add servers items, quest, locale and so on, everything that is in /db/ folder.
As you can see, there's the filepath for each moddable part, we will edit this part when we have edited what we want, for our case, it's an item. I want to edit my sicc item case to have more slots, the item ID is : 5d235bb686f77443f4331278. So i copy the file 5d235bb686f77443f4331278.json in ServerDir/db/items and i paste it in ServerDir/user/mods/Author-MyModName-version/db/items/. The file path must be the same as where you copy the file you want to mod.
I open my file up with any IDE, i prefer VScodium personnaly, and make my changes. After that i save and close the file.
Now that i edited my file, i go back to my mod.config.json and i go into the items brackets for adding my item. For me it will looks like this :