unixtime_milliseconds_todatetime

unixtime_milliseconds_todatetime converts a Unix timestamp that’s expressed in whole milliseconds since 1970-01-01 00:00:00 UTC to an APL datetime value.

Use the function whenever you ingest data that stores time as epoch milliseconds (for example, JSON logs from NGINX or metrics that follow the StatsD line protocol). Converting to datetime lets you bin, filter, and visualize events with the rest of your time-series data.

Usage#

Syntax#

unixtime_milliseconds_todatetime(milliseconds)

Parameters#

Returns#

A datetime value that represents the given epoch milliseconds at UTC precision (1 millisecond).

Use case example#

The HTTP access logs keep the timestamp as epoch milliseconds and you want to convert the values to datetime.

Query

['sample-http-logs']
| extend epoch_milliseconds = toint(datetime_diff('Millisecond', _time, datetime(1970-01-01)))
| extend datetime_standard = unixtime_milliseconds_todatetime(epoch_milliseconds)
| project _time, epoch_milliseconds, datetime_standard

Run in Playground

Output

This query converts the timestamp to epoch milliseconds and then back to datetime for demonstration purposes.

List of related functions#

• unixtime_microseconds_todatetime: Converts a Unix timestamp expressed in whole microseconds to an APL datetime value.
• unixtime_nanoseconds_todatetime: Converts a Unix timestamp expressed in whole nanoseconds to an APL datetime value.
• unixtime_seconds_todatetime: Converts a Unix timestamp expressed in whole seconds to an APL datetime value.

Other query languages#