text: ----test pv_os_run_info view
  select count(*)>=0 from gs_os_run_info; 
  
  ----test pv_session_memory_detail view
  select count(*)>=0 from gs_session_memory_detail;
  
  ----test pg_shared_memory_detail view
  select count(*)>=0 from gs_shared_memory_detail;
  
  ----test pv_session_time view
  select SCHEMANAME,VIEWNAME, DEFINITION from pg_views where viewname ='pv_session_time';
  
  select * from gs_session_time where 1=2;
  
  select count(*) from (select * from gs_session_time limit 1);
  
  ----test pv_file_stat view
  select SCHEMANAME,VIEWNAME, DEFINITION from pg_views where viewname ='pv_file_stat';
  
  select count(*)>=0 from gs_file_stat; 
  
  ----test pv_redo_stat view
  select SCHEMANAME,VIEWNAME, DEFINITION from pg_views where viewname ='pv_redo_stat';
  
  ----test pv_session_stat view
  select SCHEMANAME,VIEWNAME, DEFINITION from pg_views where viewname ='pv_session_stat';
  
  select * from gs_session_stat where 1=2;
  
  select * from gs_session_stat where statid = -1;
  
  select * from gs_session_memory where 1=2;
  
  select count(*)>=0 from gs_session_memory;
  
  select * from gs_total_memory_detail where 1=2;
  
  select count(*) from (select * from gs_total_memory_detail limit 1);
  
  ----test total_cpu function
  select total_cpu()>0;
  
  ----test get_hostname function
  select get_hostname()>'0';
  
  ----test total_memory function
  select total_memory()>0;
  
  ----test sessionid2pid function
  select sessionid2pid('123.321');
  
  ----test pv_session_memctx_detail
  select pv_session_memctx_detail(0, '');
  select pv_session_memctx_detail(1, '');
  create table qazxsw(pid bigint);
  insert into qazxsw select pg_backend_pid();
  select pv_session_memctx_detail(pid, 'TopMemoryContext') from qazxsw;
  