andishgar opened a new issue, #46177: URL: https://github.com/apache/arrow/issues/46177
### Describe the enhancement requested According the below comments https://github.com/apache/arrow/blob/c2ec1cda88918a3920b7b29eca8d2e3ca7a49fb2/cpp/src/arrow/compute/kernel.h#L445-L465 preallocate does not have an effect on string output types compute function and even I found out the same rule is obeyed by the following compute functions (I've already changed the code for myself to use the second buffer of output instead of allocating a new buffer and I pass all the relevant) https://github.com/apache/arrow/blob/c2ec1cda88918a3920b7b29eca8d2e3ca7a49fb2/cpp/src/arrow/compute/kernels/scalar_cast_string.cc#L340-L343 However, I found the offset_buffer is allocated in preallocate mode according to the below code https://github.com/apache/arrow/blob/c2ec1cda88918a3920b7b29eca8d2e3ca7a49fb2/cpp/src/arrow/compute/exec.cc#L286-L308 ### Component(s) C++ -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@arrow.apache.org.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
