It would be extremely useful and conserve storage space to have what I would call an attachment repository. The idea being a file is uploaded once and then multiple features in multiple feature classes can be pointed to the same file. The way ArcGIS currently works if for all those features to have that file attached, I must upload the same file for every feature, which causes unnecessary growth of disk storage.
For example, say I have a parcel GIS layer and I want to attach a PDF of the plat so my users can quickly review the plat when researching a property. If I have a plat with fifty lots, I must upload fifty copies of the PDF to my geodatabase as attachments. Then let's say the subdivision is re-platted. I now must upload another fifty copies of the replat PDF to the geodatabase. That is one hundred PDFs being stored in the geodatabase when only two PDFs are needed.
My concept of an attachment repository is a new item type, like a feature class, mosaic dataset, etc. A geodatabase (or whatever method would be appropriate to store this new item type) could have multiple repositories. The repository should have privileges like any other GIS item. That way you could have curators that manage the repository and users who can only view the files. When a user goes to attach a file to a feature there is an option to upload a new file or add from a repository. Another benefit is if the attachment is updated in the repository then all the features referencing the attachment get the update automatically.
Some other ideas are:
- give users the ability to define metadata fields or tags when creating the attachment repository to help find the correct file
- make attachment repositories special items in ArcGIS Online/Enterprise to allow for searching and management directly in ArcGIS Online/Enterprise
- ability to get URLs to files in the repository to embed the URLs in things like web map pop-ups
- ability to have attachment repositories store login credentials to popular cloud storage solutions so the "attachment" is just a pointer to the file in cloud storage but the ArcGIS user is not prompted to sign in to the cloud storage provided since the repository is handling that. Then if the credentials are changed for the cloud storage provider the credentials only must be updated once per repository instead of for each file. This way organizations have more choices of where to store their files and not be forced to move their files into ArcGIS.
I do not want or expect this to be a replacement for a full featured document management solution. However, it could provide the foundation for third party document management solutions to integrate better with ArcGIS, or at least allow small organizations that are already invested in Esri to create a simple document management solution inside their GIS.