text: --+ holdcas on;
  --test current timestamp doesn't change as the session time zone setting
  set timezone '+02:30';
  set @x1=(select sys_timestamp);
  set timezone '+01:30';
  set @x2=(select sys_timestamp);
  select if(hour(@x2)=hour(@x1),'ok','nok');
  drop variable @x2,@x1;
  
  set timezone '+02:30';
  set @x1=(select systimestamp);
  set timezone '+01:30';
  set @x2=(select systimestamp);
  select if(hour(@x2)=hour(@x1),'ok','nok');
  drop variable @x2,@x1;
  
  drop table if exists t;
  create table t(i string unique);
  set timezone '+4:00';
  insert into t select timediff(sys_timestamp,utc_timestamp());
  set timezone '+2:00';
  insert into t select timediff(sys_timestamp,utc_timestamp());
  drop table if exists t;
  set timezone 'Asia/Seoul';
  
  
  
  --+ holdcas off;
  