!in~

This page explains how to use the !in~ operator in APL.

The !in~ operator in APL filters records based on whether a value doesn't match any element in a specified set using case-insensitive comparison. Use this operator to exclude records where a field value equals one of several values regardless of letter case, which is more concise and efficient than chaining multiple inequality checks with and. The !in~ operator works with any scalar type, including strings, numbers, booleans, datetime values, and dynamic arrays.

Use the !in~ operator when you need to exclude specific values with case-insensitive matching, such as filtering out known HTTP methods or status codes regardless of their capitalization in the data.

Usage

Syntax

APL

Expression !in~ (Value1, Value2, ...)

Parameters

Name	Type	Required	Description
Expression	scalar	Yes	The value to check against the exclusion set, ignoring letter case.
Value	scalar or tabular	Yes	The values to exclude. Specify individual scalar values, a dynamic array, or a subquery. When using a subquery with multiple columns, APL uses the first column. The operator supports up to 1,000,000 unique values in the set.

Returns

Returns true if the expression value doesn't match any value in the specified set (case-insensitive). Returns false otherwise.

Use case examples

Filter HTTP logs to exclude certain methods regardless of case.

Query

APLRun in Playground

['sample-http-logs']
| where method !in~ ('options', 'head')
| project _time, method, uri, status

Output

_time	method	uri	status
2024-10-17 10:15:00	GET	/api/users	200
2024-10-17 10:16:30	POST	/api/data	201
2024-10-17 10:17:45	DELETE	/api/item	204

This query filters the HTTP logs to exclude OPTIONS and HEAD requests regardless of case, helping you focus on substantive requests.

Exclude internal span kinds regardless of case variations.

Query

APLRun in Playground

['otel-demo-traces']
| where kind !in~ ('internal', 'producer', 'consumer')
| project _time, trace_id, ['service.name'], kind, duration

Output

_time	trace_id	service.name	kind	duration
2024-10-17 11:00:00	abc123	frontend	server	45ms
2024-10-17 11:00:05	def456	checkout	client	120ms
2024-10-17 11:00:10	ghi789	cart	Server	30ms

This query filters traces to exclude internal and messaging spans, helping you focus on client-server interactions.

Performance considerations

When two operators perform the same task, use the case-sensitive one (!in) for better performance. Use !in~ only when case-insensitive exclusion is necessary.

Use with dynamic arrays

When you pass a dynamic array with nested arrays, APL flattens them into a single list. For instance, x !in~ (dynamic(['a', ['b', 'c']])) is equivalent to x !in~ ('a', 'b', 'c').

APL

let excluded_methods = dynamic(['options', 'head', 'trace']);
['sample-http-logs']
| where method !in~ (excluded_methods)

in: Use for case-sensitive matching to include values.
!in: Use for case-sensitive exclusion. Better performance than !in~.
in~: Use for case-insensitive matching to include values.
where: Use to filter rows based on conditions. The !in~ operator is commonly used within where clauses.
!~: Use for single value case-insensitive inequality checks. Use !in~ when checking against multiple values.