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,
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,