You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues-all@impala.apache.org by "shajini thayasingh (Jira)" <ji...@apache.org> on 2022/04/14 18:20:00 UTC
[jira] [Comment Edited] (IMPALA-11127) Document the UTF8_MODE query option and relavent string functions
[ https://issues.apache.org/jira/browse/IMPALA-11127?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17522480#comment-17522480 ]
shajini thayasingh edited comment on IMPALA-11127 at 4/14/22 6:19 PM:
----------------------------------------------------------------------
[~stigahuang] please tell me the upstream location to add the contents I have prepared in this shared [doc|https://docs.google.com/document/d/1xrReJSmxtnqyw6NRIC9WNYXCtNgP8YDDOsC6wba6BeQ/edit#]
was (Author: shajini):
[~stigahuang] please tell me to the upstream location to add the contents I have prepared in this shared [doc|https://docs.google.com/document/d/1xrReJSmxtnqyw6NRIC9WNYXCtNgP8YDDOsC6wba6BeQ/edit#]
> Document the UTF8_MODE query option and relavent string functions
> -----------------------------------------------------------------
>
> Key: IMPALA-11127
> URL: https://issues.apache.org/jira/browse/IMPALA-11127
> Project: IMPALA
> Issue Type: Documentation
> Affects Versions: Impala 4.1.0
> Reporter: Quanlong Huang
> Assignee: shajini thayasingh
> Priority: Major
>
> Since IMPALA-2019 is resolved, we can document the UTF8_MODE query option added in it now. The query option will turn on the UTF-8 aware behavior of string functions. The relevant string functions and their UTF-8 aware behaviors are:
> * LENGTH(STRING a)
> ** returns the number of UTF-8 characters instead of bytes
> * SUBSTR(STRING a, INT start [, INT len])
> SUBSTRING(STRING a, INT start [, INT len])()
> ** the substring start position and length is counted by UTF-8 characters instead of bytes
> * REVERSE(STRING a)
> ** the unit of the operation is a UTF-8 character, ie. it won't reverse bytes inside a UTF-8 character.
> * INSTR(STRING str, STRING substr[, BIGINT position[, BIGINT occurrence]])
> LOCATE(STRING substr, STRING str[, INT pos])
> ** These functions have an optional position argument. The return values are also positions in the string. In UTF-8 mode, these positions are counted by UTF-8 characters instead of bytes.
> * mask functions
> ** The unit of the operation is a UTF-8 character, ie. they won't mask the string byte-to-byte.
> * upper/lower/initcap
> ** These functions will recognize non-ascii characters and transform them based on the current locale used by the Impala process.
--
This message was sent by Atlassian Jira
(v8.20.1#820001)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-all-unsubscribe@impala.apache.org
For additional commands, e-mail: issues-all-help@impala.apache.org