I’m new to UE4, and I just found the DataTable thing today, it seems handy for creating items or weapons etc. I already know how to create custom rows and how to manage table assets in the Content folder, I wonder if I create a few tables inside some specific folder, can I some how access to them at runtime, with out setting references in blueprints? For example, in runtime, do I have a way to enumerate all assets in the Content folder, and filter these tables out, and just load them?
All information asset you see in Content Browser is stored in asset registry, and same as Content Browser you can query it and read it
Also note that you can create your own custom asset types as what assets in reality are serialized UObjects. If asset editor is not specified for asset type UE4 editor will open asset in property editor which shows properties of UObject of assets (according to UPROPERTY specifiers)
Most easiest way is to make UDataAsset class
But it a short cut which as limits. Creating new asset type properly requires more steps, but with it you can create it from same menu as any other assets, customize it, create thumbnail preview, create right click actions, support file importing and finally make your own editor for it (again by default simple property editor is opened). Here some good tutorial on that:
Best way to learn it is to check how other asset types been made in engine source code (dont be afraid to check it out)