I got a question the other week that seemed quite simple, or at least straightforward, on first impression. That is, "what are the supported data types for data stored in ArcGIS Data Stores, and what are the size and name limits as well?" Unfortunately, simple doesn't always mean easy, and providing actual documentation to support my answer took me down the Esri Support rabbit hole and now to GeoNet.
When I first got asked the question, I thought it was going to be simple to answer because Esri has documented such information for enterprise geodatabases forever. For example, if someone wants to know about supported data types in enterprise geodatabases backed by PostgreSQL, they can visit PostgreSQL data types supported in ArcGIS—Help | ArcGIS Desktop. Or, if someone wants to know about field name limits for enterprise geodatabases backed by SQL Server, the can visit Enterprise geodatabase size and name limits—Help | ArcGIS Desktop. There has to be similar concise, consolidated information for the ArcGIS Data Stores, right?
As we all know, ArcGIS Data Store has three components/products:
ArcGIS Data Store is an application that lets you easily configure data storage for the hosting server used with your portal. If you are not a database expert, ArcGIS Data Store provides you with a convenient setup and configuration experience that creates the following different types of data stores.
- Relational data store—Stores your portal's hosted feature layer data, including hosted feature layers created as output from spatial analysis tools run in the portal
- Tile cache data store—Stores caches for your portal's hosted scene layers
- Spatiotemporal big data store—Archives real-time observational data that you can use with an ArcGIS Server running ArcGIS GeoEvent Server that is federated with your portal; also stores the results generated using ArcGIS GeoAnalytics Server tool
Esri doesn't like to dive into the weeds on what actual products those data stores are implemented on, so I won't go down that route, i.e., I won't go visit company X's website because I know the relational data store is built on company X's product.
Looking at the three data stores, there probably isn't a need to know data types for the tile cache data store since ArcGIS software is building those caches and interacting with them. There are images and some metadata, not much to concern the user. I can't say the same can be said for the other two data stores, especially the relational data store.
I get that ArcGIS Data Stores are "managed data stores," and the user isn't supposed to concern themselves with any details because ArcGIS software takes care of it, like magic. For the basic/common/typical user, I agree, but for some power users and administrators, I disagree. So I continued on...
I looked all over the ArcGIS Enterprise | ArcGIS Enterprise site, and thought maybe the ArcGIS Data Store 10.6 system requirements—ArcGIS Enterprise system requirements | ArcGIS Enterprise page would have some insight. Nope. Then I thought, the data stores are for holding content from Portal, so maybe this is all laid out in Portal or ArcGIS Online documentation.
Hosted feature layers are a common item that would be stored in an ArcGIS Data Store, and they would be a good candidate for knowing information about supported data types, size and naming limits, etc.... I checked out Publish hosted feature layers—Portal for ArcGIS | ArcGIS Enterprise ; but unfortunately, that page only talks about the types of data file formats one can publish to Portal, it doesn't say anything about supported data types? Since I can publish the contents of a file geodatabase as a hosted feature layer, does that imply all of the supported data types and limits for ArcGIS Data Stores are the same as the file geodatabase?
I know I am not the first one to want this information. Dan Mallett asked a very similar question ( maximum limits of Hosted Feature Service ) back in 2014, to no avail. Deiro Nicanor Gonzalez asked a similar question ( ArcGIS Online maximun string field length ) back in 2015. Although people did respond to Deiro's question, the responses were fragmented with no clear direction to the documentation.
Anyone know how and where Esri documents this information?