I spent a good bit of time looking for the definitions/descriptions of the TMSCHEMA DMVs that allow us to view metadata and monitor the health of SSAS 2016 tabular models. As far as I can tell there are no details about them on any Microsoft site. Many of the columns are obvious, but there are a few fields that show IDs rather than descriptions (e.g., ExplicitDataType in TMSCHEMA_COLUMNS, Type in TMSCHEMA_DATA_SOURCES). It would be great to get the DMVs documented similar to the MDSCHEMA DMVs as they are quite useful for tasks like documenting your tabular model. Since the TMSCHEMA DMVs work in Azure Analysis Services as well, I have logged this request on the Azure AS User Voice for that. Please lend me a vote so we can make this information more easily available.