[ARROW-11693] [C++] Add string length kernel

• Type: New Feature
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 4.0.0
• Component/s: C++
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/27555
• Assignee: Eduardo Ponce
• Reporter: Neal Richardson
• Created: 18/Feb/21 22:51
• Updated: 11/Jan/23 08:21
• Resolved: 24/Mar/21 22:16

Description

We have "binary_length" but that doesn't handle UTF-8 the way we need for this. Example (from R):

> string <- "áéíóú"
> nchar(string)
[1] 5
> arrow:::call_function("binary_length", Scalar$create(string))
Scalar
10

cc Maarten Breddels Antoine Pitrou Joris Van den Bossche

Issue Links

• is a child of: ARROW-555 [C++] String algorithm library for StringArray/BinaryArray
• links to: GitHub Pull Request #9786