Add support for MariaDB max_statement_time

include/proxysql_structs.h

@@ -200,6 +200,7 @@ enum mysql_variable_name {
 	SQL_MAX_HEAP_TABLE_SIZE,
 	SQL_MAX_JOIN_SIZE,
 	SQL_MAX_SORT_LENGTH,
+	SQL_MAX_STATEMENT_TIME,
 	SQL_OPTIMIZER_PRUNE_LEVEL,
 	SQL_OPTIMIZER_SEARCH_DEPTH,
 	SQL_OPTIMIZER_SWITCH,
@@ -1157,6 +1158,7 @@ mysql_variable_st mysql_tracked_variables[] {
 	{ SQL_MAX_HEAP_TABLE_SIZE,        SETTING_VARIABLE, false, false, true,  false, (char *)"max_heap_table_size",        NULL, (char *)"18446744073709547520" , false} ,
 	{ SQL_MAX_JOIN_SIZE,              SETTING_VARIABLE, false, false, true,  false, (char *)"max_join_size",              NULL, (char *)"18446744073709551615" , false} ,
 	{ SQL_MAX_SORT_LENGTH,            SETTING_VARIABLE, false, false, true,  false, (char *)"max_sort_length",            NULL, (char *)"" , false} ,
+	{ SQL_MAX_STATEMENT_TIME,         SETTING_VARIABLE, false, false, true,  false, (char *)"max_statement_time",         NULL, (char *)"" , false} ,
 	{ SQL_OPTIMIZER_PRUNE_LEVEL,      SETTING_VARIABLE, false, false, true,  false, (char *)"optimizer_prune_level",      NULL, (char *)"" , false} ,
 	{ SQL_OPTIMIZER_SEARCH_DEPTH,     SETTING_VARIABLE, false, false, true,  false, (char *)"optimizer_search_depth",     NULL, (char *)"" , false} ,
 	{ SQL_OPTIMIZER_SWITCH,           SETTING_VARIABLE, true,  false, false, false, (char *)"optimizer_switch",           NULL, (char *)"" , false} ,

lib/MySQL_Session.cpp

@@ -95,6 +95,7 @@ static const std::set<std::string> mysql_variables_numeric = {
 	"max_heap_table_size",
 	"max_join_size",
 	"max_sort_length",
+	"max_statement_time",
 	"optimizer_prune_level",
 	"optimizer_search_depth",
 	"optimizer_use_condition_selectivity",