| Bug #105966 | Contribution by Tencent:missing session track info when set names with collation | ||
|---|---|---|---|
| Submitted: | 23 Dec 2021 3:41 | Modified: | 13 Jan 2022 7:33 |
| Reporter: | yuxiang jiang (OCA) | Email Updates: | |
| Status: | Verified | Impact on me: | |
| Category: | MySQL Server: Charsets | Severity: | S4 (Feature request) |
| Version: | all | OS: | Any |
| Assigned to: | CPU Architecture: | Any | |
| Tags: | collation, Contribution, session track | ||
[23 Dec 2021 3:47]
yuxiang jiang
set names with more info added (*) I confirm the code being submitted is offered under the terms of the OCA, and that I am authorized to contribute it.
Contribution: 0001-feature-Return-more-infomation-when-set-names.patch (application/octet-stream, text), 2.46 KiB.
[23 Dec 2021 5:08]
MySQL Verification Team
Hello yuxiang jiang, Thank you for the report and contribution. regards, Umesh
[13 Jan 2022 7:33]
yuxiang jiang
Contribution by Tencent
[26 Jan 2022 8:40]
Frederic Descamps
This contribution has been processed by our development team and has been accepted. It will be included into a future release. Thank you again.
Description: After execute 'set names' statement with collation, session track do not return the newly specified collation. From code below we know that character_set_connection and collation_connection use the same CHARSET_INFO variables. --- static Sys_var_struct Sys_character_set_connection( "character_set_connection", "The character set used for " "literals that do not have a character set introducer and for " "number-to-string conversion", SESSION_VAR(collation_connection), NO_CMD_LINE, offsetof(CHARSET_INFO, csname), DEFAULT(&default_charset_info), NO_MUTEX_GUARD, IN_BINLOG, ON_CHECK(check_charset_not_null), ON_UPDATE(fix_thd_charset)); static Sys_var_struct Sys_collation_connection( "collation_connection", "The collation of the connection " "character set", SESSION_VAR(collation_connection), NO_CMD_LINE, offsetof(CHARSET_INFO, name), DEFAULT(&default_charset_info), NO_MUTEX_GUARD, IN_BINLOG, ON_CHECK(check_collation_not_null), ON_UPDATE(fix_thd_charset)); --- But as we show variables like collation_connection and character_set_connection, they have different value returned. So when execute set names with collation, although we know charset changed, but the detailed collation info is missing. How to repeat: set session_track_system_variables='time_zone,autocommit,character_set_client,character_set_results,character_set_connection,collation_connection'; set names 'utf8mb4' collate 'utf8mb4_unicode_ci'; then check session tracker return Suggested fix: Add collation_connection when set names. diff --git a/sql/set_var.cc b/sql/set_var.cc index 35fb210..5c7fcf7 100644 --- a/sql/set_var.cc +++ b/sql/set_var.cc @@ -1174,6 +1174,9 @@ int set_var_collation_client::update(THD *thd) LEX_CSTRING cs_connection= {"character_set_connection", sizeof("character_set_connection") - 1}; thd->session_tracker.get_tracker(SESSION_SYSVARS_TRACKER)->mark_as_changed(thd, &cs_c + LEX_CSTRING cs_collation= {"collation_connection", + sizeof("collation_connection") - 1}; + thd->session_tracker.get_tracker(SESSION_SYSVARS_TRACKER)->mark_as_changed(thd, &cs_c } if (thd->session_tracker.get_tracker(SESSION_STATE_CHANGE_TRACKER)->is_enabled()) thd->session_tracker.get_tracker(SESSION_STATE_CHANGE_TRACKER)->mark_as_changed(thd,