You want to identify the SQL statements consuming more resources in Oracle.
“V$SQLSTATS" view displays performance statistics for SQL statements that have recently executed. You can also use "V$SQL” and “V$SQLAREA" to report on SQL resource usage.
"V$SQLSTATS” is faster and retains information for a longer period of time, but contains only a subset of the columns in “V$SQL" and "V$SQLAREA”.
select * from( select sql_text ,buffer_gets ,disk_reads ,sorts ,cpu_time/1000000 cpu_sec ,executions ,rows_processed from v$sqlstats order by cpu_time DESC) where rownum < 20;