Update LEN function behavior details in documentation

[rashidsarwar]

Clarified behavior of LEN function with UnicodeCharacterBehavior property on model

[prmerger-automator]

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[jeroenterheerdt]

after we agree with this update we should make sure to update all the other pages

[jeroenterheerdt]

I'd recommend we don't make it so dependent on the january release in the docs. I'd just say: In recent versions, you can set the UnicodeCharacterBehavior property.

[jeroenterheerdt]

isn't there a ' missing? len('🍕')? same a couple of lines earlier.

[v-dirichards]

#label:"aq-pr-triaged"
@MicrosoftDocs/public-repo-pr-review-team

[Copilot]

Pull request overview

This PR updates the documentation for the DAX LEN function to clarify its behavior with the new UnicodeCharacterBehavior model property. The update explains how the function handles Unicode characters differently based on whether the property is set to CodeUnits (default, legacy behavior) or CodePoints (new behavior), using emoji as an example.

• Adds documentation explaining the UnicodeCharacterBehavior property's impact on LEN function behavior
• Provides examples showing how emoji characters are counted differently with CodeUnits vs CodePoints settings

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[Copilot]

The string literal '😀 is missing a closing single quote. It should be '😀' to properly close the string.

Suggested change

	- With CodeUnits default value of UnicodeCharacterBehavior property, the len('😀) will return => 2. This is old behavior of LEN function.
	- With CodePoints value of UnicodeCharacterBehavior property, the len('😀) will return => 1. This will be new behavior of LEN function.
	- With CodeUnits default value of UnicodeCharacterBehavior property, the len('😀') will return => 2. This is old behavior of LEN function.
	- With CodePoints value of UnicodeCharacterBehavior property, the len('😀') will return => 1. This will be new behavior of LEN function.

[Copilot]

The function name should be consistently uppercase. Change "len('😀)" to "LEN('😀')" to match the standard DAX function naming convention used throughout the documentation (e.g., line 14, 31, 33, 41).

Suggested change

	- With CodeUnits default value of UnicodeCharacterBehavior property, the len('😀) will return => 2. This is old behavior of LEN function.
	- With CodePoints value of UnicodeCharacterBehavior property, the len('😀) will return => 1. This will be new behavior of LEN function.
	- With CodeUnits default value of UnicodeCharacterBehavior property, the LEN('😀') will return => 2. This is old behavior of LEN function.
	- With CodePoints value of UnicodeCharacterBehavior property, the LEN('😀') will return => 1. This will be new behavior of LEN function.

[Copilot]

The function name should be consistently uppercase. Change "len('😀)" to "LEN('😀')" to match the standard DAX function naming convention used throughout the documentation (e.g., line 14, 31, 33, 41).

Suggested change

	- With CodeUnits default value of UnicodeCharacterBehavior property, the len('😀) will return => 2. This is old behavior of LEN function.
	- With CodePoints value of UnicodeCharacterBehavior property, the len('😀) will return => 1. This will be new behavior of LEN function.
	- With CodeUnits default value of UnicodeCharacterBehavior property, the LEN('😀') will return => 2. This is old behavior of LEN function.
	- With CodePoints value of UnicodeCharacterBehavior property, the LEN('😀') will return => 1. This will be new behavior of LEN function.

[Copilot]

Consider replacing the informal "=>" notation with clearer language such as "will return 2" or "returns 2" to be consistent with more formal technical documentation style.

Suggested change

	- With CodeUnits default value of UnicodeCharacterBehavior property, the len('😀) will return => 2. This is old behavior of LEN function.
	- With CodePoints value of UnicodeCharacterBehavior property, the len('😀) will return => 1. This will be new behavior of LEN function.
	- With CodeUnits default value of UnicodeCharacterBehavior property, the len('😀) returns 2. This is old behavior of LEN function.
	- With CodePoints value of UnicodeCharacterBehavior property, the len('😀) returns 1. This will be new behavior of LEN function.

[Copilot]

The new documentation about UnicodeCharacterBehavior contradicts the existing remark on line 31 which states "LEN always counts each character as 1, no matter what the default language setting is." Since the behavior now changes based on the UnicodeCharacterBehavior property setting, line 31 should be updated to clarify that this statement applies only to the default CodeUnits behavior, or be revised to reflect the conditional behavior.

[Copilot]

The month name "january" should be capitalized to "January" for proper noun capitalization. Additionally, "user" should be "users" or "the user" for better grammar.

Suggested change

	- Starting with desktop january release, user can set new model property UnicodeCharacterBehavior. Depending on value of the property, the output of LEN(<text>) function changes.
	- Starting with the January desktop release, users can set the new model property UnicodeCharacterBehavior. Depending on value of the property, the output of LEN(<text>) function changes.

[Copilot]

The string literal '😀 is missing a closing single quote. It should be '😀' to properly close the string.

Suggested change

	- With CodeUnits default value of UnicodeCharacterBehavior property, the len('😀) will return => 2. This is old behavior of LEN function.
	- With CodePoints value of UnicodeCharacterBehavior property, the len('😀) will return => 1. This will be new behavior of LEN function.
	- With CodeUnits default value of UnicodeCharacterBehavior property, the len('😀') will return => 2. This is old behavior of LEN function.
	- With CodePoints value of UnicodeCharacterBehavior property, the len('😀') will return => 1. This will be new behavior of LEN function.