Applies to:
- Plan -
- Deployment -
Summary
Logs page shows “Field ‘spans’ not found in schema” or parser errors. Cause: a saved custom column expression references span-level fields or uses invalid bracket indexing. Fix: edit or remove the offending custom column or use the CLI workaround.What is happening
The Logs table sends every saved custom column expression with the rows query. If one column references a field that is not present in the query shape (for examplespans in the summary shape) or uses invalid indexing, the whole rows query fails and the UI shows the error.
CSV export fails for the same reason. The CLI does not send saved columns, so it can succeed.
Fix or suggestion
Option 1: edit or delete the offending custom column (recommended)
- Go to the project Logs.
- Click Display on the right.
- Find the custom columns that reference
spansor use bracket indexing with non-numeric keys. - Edit the expression to use dot-quoted keys, or delete the column.
- Save the Display settings and reload the Logs page.
Option 2: identify the column via API and fix remotely
-
Get the project ID:
-
List the project’s Logs table custom columns:
-
Inspect the returned column
exprvalues for references tospansor bracketed non-numeric keys. Edit or delete the offending column via the UI or API.
To narrow down the cause, toggle your Logs view from Traces to Spans. The error message shown there will identify the specific broken expression.
Temporary workaround
Use the CLI to list spans explicitly. The CLI does not send saved columns.spans shape in SQL:
How to confirm it worked
- The Logs page loads rows without the “Field ‘spans’ not found in schema” error.
- CSV export downloads successfully and displays rows.
Notes
- Bracket indexing only accepts numeric indices. Use dot-quoted keys for object properties with special characters:
parent."key with spaces".child."Label". - The CLI workaround works because it does not attach saved custom columns to the rows query.