title: Relation between DBA_HIST_SQLSTAT and GV$SQL
body: <p>I was trying to create a dashboard comparing historical executions and current executions of multiple SQL statements. I have noticed some differences between stats in GV$SQL and DBA_HIST_SQLSTAT. Could you please help us to understand below point. </p>
  
  <p>For eg: For one SQL_ID i have 37 rows in DBA_HIST_SQLSTAT and DBA_HIST_SNAPSHOT (has same PHV and same child number for all). Sum of executions_delta column gives me 91. However, as per GV$SQL, EXECUTIONS is only 40. </p>
  
  <p>Min begin interval time from DBA_HIST_SNAPSHOT is 23/May/2018 and max end interval time is 5/June/2018. First_load_time and last_load_time in v$sql is 31 Jan 2018 and 18 June 2018 respectively. </p>
  
  <p>Please help me to understand why DBA_HIST_SNAPSHOT could have more number of executions within a shorter period of time comparing to gv$sql values. </p>