[jira] [Updated] (IMPALA-12718) trim() functions are lack of utf-8 support

["Quanlong Huang (Jira)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/IMPALA-12718?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Quanlong Huang updated IMPALA-12718:
------------------------------------
    Labels: ramp-up  (was: )

> trim() functions are lack of utf-8 support
> ------------------------------------------
>
>                 Key: IMPALA-12718
>                 URL: https://issues.apache.org/jira/browse/IMPALA-12718
>             Project: IMPALA
>          Issue Type: Bug
>            Reporter: Quanlong Huang
>            Priority: Critical
>              Labels: ramp-up
>
> The following string functions are lack of UTF-8 support:
> {noformat}
> BTRIM(STRING a, STRING chars_to_trim)
> LTRIM(STRING a, STRING chars_to_trim)
> RTRIM(STRING a , STRING chars_to_trim)
> {noformat}
> Here is an issue reported by our user:
> {noformat}
> [localhost:21050] default> select rtrim('价格，', '，');
> +-----------------------+
> | rtrim('价格，', '，') |
> +-----------------------+
> | 价�                   |
> +-----------------------+{noformat}
> The result is the same if setting utf8_mode=true. Note that the comma used in the above strings is Chinese punctuation mark '，' , not English(ASCII) mark ','.
> The cause is that the Chinese character '，' is used as a char set. The utf8 encoding of these characters:
>  * '价': 0xe4 0xbb 0xb7
>  * '格': 0xe6 0xa0 0xbc
>  * '，': 0xef 0xbc 0x8c
> Each character is encoded into 3 bytes. The last byte of '格' is 0xbc which also appears in the bytes of '，'. So it's removed as well. The result is a string of '价' and the first two bytes of '格'. The last character becomes a malformed unicode so it's replaced with '�'.



--
This message was sent by Atlassian Jira
(v8.20.10#820010)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-all-unsubscribe@impala.apache.org
For additional commands, e-mail: issues-all-help@impala.apache.org