Inspect empty time buckets before interpreting an Azure Workbook chart window

Source facts

Microsoft notes that summarize omits a result row when a time bucket has no items. Depending on where those empty buckets fall within the selected range, the workbook chart’s displayed time window can shift. Its chart guidance contrasts this behavior with make-series. Microsoft Learn.

Applicability

Use this review for a time chart driven by a log query using summarize. Identify the selected interval, bin size and expected empty periods. Do not treat an omitted row as a measured zero, or assume the chart’s visible edges prove the query’s requested time range.

DSE recommendation

DSE recommends inspecting the underlying query results before altering the incident narrative. Decide how the report should represent empty intervals and compare the source’s alternatives with that reporting requirement. Label any explicit zero-filling choice so readers can distinguish it from a recorded measurement. Test the revised chart with a known sparse dataset.

Verification

Use an approved dataset containing empty buckets at the beginning, middle and end of the requested range. Compare result rows and chart boundaries before and after the proposed query change. Confirm that the displayed period and empty-data treatment match the documented intent. Preserve the query and sparse-data examples so later visualization edits can be checked against the same expectation.

Official references

Microsoft Learn: Azure Monitor workbook chart visualizations.