in~

Use the in~ operator when you need case-insensitive matching against multiple values, such as when filtering logs where the case of values might vary (for example, HTTP methods that could be 'GET', 'get', or 'Get').

Usage#

Syntax#

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

Parameters#

Name	Type	Required	Description
Expression	scalar	Yes	The value to find in the given set, ignoring letter case.
Value	scalar or tabular	Yes	The values to compare against the expression. 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 matches any value in the specified set (case-insensitive). Returns false otherwise.

Use case examples#

Log analysisOpenTelemetry traces

Filter HTTP logs by method regardless of case.

Query

['sample-http-logs']
| where method in~ ('get', 'post')
| project _time, method, uri, status

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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	get	/api/items	200

This query filters the HTTP logs to return requests with GET or POST methods, regardless of how the method is capitalized in the data.

Identify traces by span kind regardless of case variations.

Query

['otel-demo-traces']
| where kind in~ ('server', 'client')
| project _time, trace_id, ['service.name'], kind, duration

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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 show spans with server or client kind, regardless of case, helping you analyze external-facing operations.

Performance considerations#

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

let methods = dynamic(['get', 'post']);
['sample-http-logs']
| where method in~ (methods)

in: Use for case-sensitive matching to include values. Better performance than in~.
!in: Use for case-sensitive exclusion. Returns true if the value isn't in the set.
!in~: Use for case-insensitive exclusion. Excludes values regardless of case.
where: Use to filter rows based on conditions. The in~ operator is commonly used within where clauses.
=~: Use for single value case-insensitive equality checks. Use in~ when checking against multiple values.

Other query languages#

Splunk SPL users

In Splunk SPL, string comparisons are case-insensitive by default. APL requires the explicit in~ operator for case-insensitive matching. Use in~ when you want to match values regardless of case.

Splunk example

index=web_logs | where method IN ("get", "post", "put")

APL equivalent

['sample-http-logs']
| where method in~ ('get', 'post', 'put')

ANSI SQL users

In ANSI SQL, the IN operator's case sensitivity depends on the database collation. APL's in~ operator explicitly performs case-insensitive matching, similar to SQL databases with case-insensitive collation.

SQL example

SELECT * FROM sample_http_logs WHERE LOWER(method) IN ('get', 'post', 'put')