Create Feature Layer with Related Table

[HSchaper]

I'm using ArcGIS Online and have been trying unsuccessfully to create a feature layer with a related table. How can I do that?

Basically, I want a feature layer similar to the Hydrant Inspection template, just with a line layer instead of a point layer. 

[JonathanMcDougall]

I'm not sure it's entirely possible in AGOL, you can "fake" it to a degree by creating a feature layer with a unique id field, then create a table with an UID there too. Adding the layer and table to a map then running the analysis tool and joining layer UID to table UID. The only problem with this is that, unlike creating a proper relationship class in ArcPro is that the ids won't be created for you and won't follow parent to guid. If you carefully manually create and enter the IDs especially in the table, you'll get some form of working relationship.

[HSchaper]

Thanks for your reply.

I'm surprised this (might) not be possible in AGOL, isn't that like a main requirement for a tool like this? Afterall, what value does data have that I can't relate to other data.

I've tried that approach you suggested, but that doesn't get the job done for me. I need the actual relationship modelled properly so I can add related data in ArcGIS Field Maps, e.g. Inspections for Hydrants. Though in my case it's inspections for pipes, hence the need for a line layer.

[HSchaper · Accepted solution]

Well I managed to create such layer using ArcGIS Pro and following this guide. It'd be great to be able to do that solely in ArcGIS Online though and avoid downloading, installing and maintaining a 1.5 GB windows client.

[JonathanMcDougall]

One thing too note, the create Relationship class tool is only available with Pro Standard and above licences, not Pro Basic.