I am using 5 day Data Cloud instance and completed the exercise as per https://trailhead.salesforce.com/content/learn/projects/create-a-data-stream-in-data-cloud/add-and-map-a-formula-field
Now when I try to explore the data I am getting below error.
"We couldn't query the data. Try again later. GackId: 1399439375-180278 (1967313880)"
How can I resolve this issue?
Summary:
The current state is that Data Explorer cannot access DMOs in a Trailhead Playground, despite correct permissions, deployed models, and no issues with SQL, columns, or filters. The referenced Known Issue (W-16736530) is misaligned because it suggests Data Explorer should still work for Unified Individual DMOs, but in practice it fails with the same error.
Description:
As of today (over a year after similar issues were first reported), the problem still persists in a fresh Trailhead Playground. Specifically, Data Explorer cannot access any Data Model Objects (DMOs) and throws the error: "Something's not right with the query. Check the columns or filter and try again." This happens regardless of which DMO is selected.
Validations Performed:
DLOs vs DMOs behavior
• Data Explorer successfully shows Data Lake Objects (DLOs)
• DMOs cannot be accessed, even when columns and filters are minimal
Permissions
• Confirmed that the Data Cloud Admin permission set is assigned
Filters
• Verified no filters are applied that would cause issues
Columns
• Verified the selected columns are valid
• Removed and re-added columns to confirm no column-level corruption
Generated SQL inspection
• Used Copy SQL and ran it in the Data Explorer query editor
• SQL executed successfully with no errors
• Confirms the error is UI-level, not an actual query failure
Model deployment
• Verified all models are deployed with no errors
Client-side cache
• Tested in incognito mode and a fresh session — same error persists
Data space validation
• Confirmed not a data space issue (tried across spaces, same result)
Known Issue Reference:
• Salesforce Known Issue: W-16736530
• Describes a limitation with Identity Users in Profile Explorer
• The documented workaround suggests using Data Explorer to access Unified Individual DMOs
• However, in this case the workaround does not resolve the issue, since the error is specifically in Data Explorer when querying DMOs
