jacktengg opened a new pull request, #69038:
URL: https://github.com/apache/doris/pull/69038
### What problem does this PR solve?
Issue Number: None
Related PR: None
Problem Summary: LEFT advances by the width declared by a UTF-8 lead byte
even when the current row ends before that width. For adjacent rows containing
E4B8 and 5A, LEFT(s, 1) can return E4B85A and persist the extra byte through
CTAS or INSERT. Traverse using byte offsets and clamp the final slice to the
current StringRef length before copying. LEFT and its STRLEFT alias now
preserve the truncated bytes without including bytes from another row.
### Release note
Fix LEFT and STRLEFT returning extra bytes for truncated UTF-8 strings.
### Check List (For Author)
- Test: Unit Test / Regression test / Manual test
- ASAN BE unit tests: function_string_left_truncated_utf8_test and
function_string_strleft_test; new test fails before the fix and passes after it
- Regression suite test_left_truncated_utf8: generate expected output
and compare it in a separate run, including constant folding, CTAS and INSERT
- Original SQL reproduction returns E4B8 for LEFT(s, 1)
- ASAN BE build, GLIBC_2.17 compatibility gate, clang-format 16, build
hygiene and clang-tidy checks passed
- Behavior changed: Yes; truncate LEFT/STRLEFT output at the current row
boundary
- Does this need documentation: No
### What problem does this PR solve?
Issue Number: close #xxx
Related PR: #xxx
Problem Summary:
### Release note
None
### Check List (For Author)
- Test <!-- At least one of them must be included. -->
- [ ] Regression test
- [ ] Unit Test
- [ ] Manual test (add detailed scripts or steps below)
- [ ] No need to test or manual test. Explain why:
- [ ] This is a refactor/code format and no logic has been changed.
- [ ] Previous test can cover this change.
- [ ] No code files have been changed.
- [ ] Other reason <!-- Add your reason? -->
- Behavior changed:
- [ ] No.
- [ ] Yes. <!-- Explain the behavior change -->
- Does this need documentation?
- [ ] No.
- [ ] Yes. <!-- Add document PR link here. eg:
https://github.com/apache/doris-website/pull/1214 -->
### Check List (For Reviewer who merge this PR)
- [ ] Confirm the release note
- [ ] Confirm test cases
- [ ] Confirm document
- [ ] Add branch pick label <!-- Add branch pick label that this PR should
merge into -->
--
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: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
