otel_histogram_merge

Merges OpenTelemetry histogram data points (explicit-boundary or exponential). Input is a dynamic propertybag containing histogram fields (e.g. $raw or pack_all()). Explicit histograms must have identical bucket boundaries to merge; mismatched boundaries return null. Exponential histograms at different scales are automatically downscaled to the coarser scale for lossless merging. Mixing explicit and exponential histograms returns null. Non-histogram rows are silently skipped.

otel_histogram_merge(histogram)

metrics
| where metric.type == "histogram" and metric.name == "http.request.duration"
| summarize merged = otel_histogram_merge($raw) by bin($time, 1h)
| extend p99 = otel_histogram_percentile(merged, 99)