isascii function to check whether a string contains only ASCII characters. It returns true if every character in the input string belongs to the ASCII character set (for example, character codes 0–127) and false otherwise.
The function is useful in scenarios where you want to detect non-ASCII text in logs, validate inputs for encoding compliance, or identify potential anomalies introduced by copy-pasted foreign characters or malformed input in user-submitted data.
For users of other query languages
If you come from other query languages, this section explains how to adjust your existing queries to achieve the same results in APL.Splunk SPL users
Splunk SPL users
Splunk SPL doesn’t have a direct equivalent to
isascii. To achieve similar functionality, you typically need to use match() or custom regular expressions. In contrast, APL provides isascii as a simple built-in function, making the check much more concise and performant.ANSI SQL users
ANSI SQL users
ANSI SQL doesn’t provide a built-in
isascii function. You often need to simulate it using regular expressions or character code checks. APL simplifies this with the dedicated isascii function.Usage
Syntax
Parameters
Returns
Abool value:
trueif all characters invalueare ASCII characters.falseif any character is outside the ASCII range.
Use case examples
- Log analysis
- OpenTelemetry traces
- Security logs
Identify non-ASCII characters in request URIs to detect unusual or malformed traffic.QueryRun in PlaygroundOutput
This query flags requests with non-ASCII characters in the
uri field. These entries can indicate abnormal requests or encoding issues in log data.