floor

Use floor when you want to convert decimal numbers to whole numbers by truncating the fractional part. For example, if a user has completed 2.7 sessions, floor returns 2 to represent fully completed sessions.

Usage#

Syntax#

floor(number)

Parameters#

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

Returns#

An integer representing the largest whole number less than or equal to the input value.

Use case examples#

Log analysisOpenTelemetry traces

Calculate completed seconds from millisecond durations.

Query

['sample-http-logs']
| extend completed_ms = floor(req_duration_ms)
| summarize request_count = count() by completed_ms
| order by completed_ms asc

Run in Playground

Output

completed_seconds	request_count
0	8540
1	2310
2	890
3	245

This query converts request durations to whole milliseconds by rounding down, then groups requests by their completion time.

Group traces by completed duration intervals.

Query

['otel-demo-traces']
| extend duration_seconds = floor(duration / 1s)
| summarize trace_count = count() by duration_seconds, ['service.name']
| order by trace_count desc

Run in Playground

Output

duration_seconds	service.name	trace_count
0	frontend	1850
0	frontend-proxy	580
599	load-generator	420
600	cart	210

This query rounds span durations down to whole seconds to analyze the distribution of trace durations per service.

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

Other query languages#

Splunk SPL users

In Splunk SPL, you use the floor function to round down values. APL's floor function works identically.

Splunk example

| eval completed_seconds = floor(duration_ms / 1000)

APL equivalent

['sample-http-logs']
| extend completed_seconds = floor(req_duration_ms / 1000)

ANSI SQL users

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

SQL example

SELECT FLOOR(request_duration / 1000) AS completed_seconds FROM logs