Find queries causing high physical read in Oracle

 Find top 10 Queries from high physical read

SELECT schema, sql_text, disk_reads, round(cpu,2) FROM
(SELECT s.parsing_schema_name schema, t.sql_id, t.sql_text, t.disk_reads,
t.sorts, t.cpu_time/1000000 cpu, t.rows_processed, t.elapsed_time
FROM v$sqlstats t join v$sql s on(t.sql_id = s.sql_id)
WHERE parsing_schema_name = 'HR'
ORDER BY disk_reads DESC)
WHERE rownum <= 10;

Find high disk read in Oracle

select username users, round(DISK_READS/Executions) DReadsExec,Executions Exec, DISK_READS DReads,sql_text
from gv$sqlarea a, dba_users b
where a.parsing_user_id = b.user_id
and Executions > 0
and DISK_READS > 100000
order by 2 desc;