set @save_session_track_system_variables=@@session_track_system_variables;
SELECT @@session.character_set_connection;
@@session.character_set_connection
latin1
SET @@session.session_track_system_variables='character_set_connection';
# tracking info on
SET NAMES 'utf8';
-- Tracker : SESSION_TRACK_SYSTEM_VARIABLES
-- character_set_connection
-- utf8mb3

SET NAMES 'big5';
-- Tracker : SESSION_TRACK_SYSTEM_VARIABLES
-- character_set_connection
-- big5

# tracking info on once
SET NAMES 'utf8';
-- Tracker : SESSION_TRACK_SYSTEM_VARIABLES
-- character_set_connection
-- utf8mb3

SET NAMES 'big5';
# tracking info on
SET NAMES 'utf8';
-- Tracker : SESSION_TRACK_SYSTEM_VARIABLES
-- character_set_connection
-- utf8mb3

# tracking info off once
SET NAMES 'big5';
SET @@session.session_track_system_variables= @save_session_track_system_variables;
#
# MDEV-22504: session tracking return incorrectly long traking data
#
set @save_optimizer_switch=@@optimizer_switch;
SET @@session.session_track_system_variables='optimizer_switch';
set optimizer_switch='index_merge=off,index_merge_union=off,index_merge_sort_union=off,index_merge_intersection=off,index_merge_sort_intersection=on,engine_condition_pushdown=on,index_condition_pushdown=off,derived_merge=off,derived_with_keys=off,firstmatch=off,loosescan=off,materialization=on,in_to_exists=off,semijoin=off,partial_match_rowid_merge=off,partial_match_table_scan=off,subquery_cache=off,mrr=on,mrr_cost_based=on,mrr_sort_keys=on,outer_join_with_cache=off,semijoin_with_cache=off,join_cache_incremental=off,join_cache_hashed=off,join_cache_bka=off,optimize_join_buffer_size=on,table_elimination=off,extended_keys=off,exists_to_in=off,orderby_uses_equalities=off,condition_pushdown_for_derived=off';
-- Tracker : SESSION_TRACK_SYSTEM_VARIABLES
-- optimizer_switch
-- index_merge=off,index_merge_union=off,index_merge_sort_union=off,index_merge_intersection=off,index_merge_sort_intersection=on,engine_condition_pushdown=on,index_condition_pushdown=off,derived_merge=off,derived_with_keys=off,firstmatch=off,loosescan=off,materialization=on,in_to_exists=off,semijoin=off,partial_match_rowid_merge=off,partial_match_table_scan=off,subquery_cache=off,mrr=on,mrr_cost_based=on,mrr_sort_keys=on,outer_join_with_cache=off,semijoin_with_cache=off,join_cache_incremental=off,join_cache_hashed=off,join_cache_bka=off,optimize_join_buffer_size=on,table_elimination=off,extended_keys=off,exists_to_in=off,orderby_uses_equalities=off,condition_pushdown_for_derived=off,split_materialized=on,condition_pushdown_for_subquery=on,rowid_filter=on,condition_pushdown_from_having=on,not_null_range_scan=off

Warnings:
Warning	1681	'engine_condition_pushdown=on' is deprecated and will be removed in a future release
set @@optimizer_switch=@save_optimizer_switch;
SET @@session.session_track_system_variables= @save_session_track_system_variables;
# End of 10.2 tests
#
# MDEV-22134 handle_fatal_signal (sig=11) in __strlen_avx2 on START
# SLAVE | Assertion
# `global_system_variables.session_track_system_variables' failed in
# Session_sysvars_tracker::init | *** buffer overflow detected ***
# (on optimized builds)
#
SET @@GLOBAL.session_track_system_variables=NULL;
ERROR 42000: Variable 'session_track_system_variables' can't be set to the value of 'NULL'
SET SESSION session_track_system_variables=NULL;
ERROR 42000: Variable 'session_track_system_variables' can't be set to the value of 'NULL'
# End of 10.3 tests
#
# MDEV-16470 - Session user variables tracker
#
# End of 10.5 tests