ceiling

Use ceiling when you want to convert decimal numbers to whole numbers by rounding up. For example, if you have 7.2 requests per second and need to provision whole server instances, ceiling ensures you allocate 8 instances rather than 7.

Usage#

Syntax#

ceiling(number)

Parameters#

Name	Type	Description
`number`	`real`	The numeric value to round up.

Returns#

An integer representing the smallest whole number greater than or equal to the input value.

Use case examples#

Log analysisOpenTelemetry traces

Round request durations up to whole milliseconds for consistent bucketing.

Query

['sample-http-logs']
| extend duration_bucket = ceiling(req_duration_ms) * 100
| summarize request_count = count() by duration_bucket
| order by duration_bucket asc

Run in Playground

Output

duration_bucket	request_count
100	1250
200	3420
300	2180
400	890

This query groups requests into 100ms buckets using ceiling to ensure all fractional durations round up to the next bucket boundary.

Calculate the minimum number of seconds to allocate for trace processing.

Query

['otel-demo-traces']
| extend duration_seconds = ceiling(duration / 1s)
| summarize avg_duration_seconds = avg(duration_seconds) by ['service.name']
| order by avg_duration_seconds desc

Run in Playground

Output

service.name	avg_duration_seconds
checkout	5
product-catalog	3
cart	2
frontend	1

This query rounds span durations up to whole seconds to estimate resource allocation per service.

floor: Rounds down to the largest integer less than or equal to the input. Use ceiling when you need to round up instead.
bin: Rounds values down to a multiple of a specified bin size. Use ceiling for simple upward rounding to integers.
round: Rounds to the nearest integer or specified precision. Use ceiling when you always need to round up.

Other query languages#

Splunk SPL users

In Splunk SPL, you use the ceil or ceiling function to round up values. APL's ceiling function works the same way.

Splunk example

| eval rounded_up = ceil(request_time)

APL equivalent

['sample-http-logs']
| extend rounded_up = ceiling(req_duration_ms)

ANSI SQL users

In ANSI SQL, the CEILING or CEIL function performs the same operation. APL's syntax is nearly identical.

SQL example

SELECT CEILING(request_duration) AS rounded_up FROM logs