Adding cool ASH mining script by Jeremy Schneider

Author: gwenshap

top-sql.sql

@@ -0,0 +1,57 @@
+-- by Jeremy Schneider, Pythian
+clear breaks
+col sql_text format a40
+col wait_class format a20
+col event format a40
+col top_obj_pct format a11
+col top_object format a30
+break on sql_id on sql_text skip 1
+
+with master as (
+select /*+ materialize */ hhh.sql_id,
+       trunc(100*count(*)/hhh.total_sess) percentage,
+       hhh.wait_class, 
+       hhh.event,
+       hhh.top_obj,
+       decode(hhh.top_obj,0,null,-1,null,trunc(100*hhh.total_top_obj/hhh.total_sess)) top_obj_pct,
+       count(*) total_samples,
+       hhh.topn
+from (
+  select hh.*,
+         first_value(hh.current_obj#) over (partition by hh.sql_id, hh.event order by hh.total_obj desc nulls last) top_obj,
+         first_value(hh.total_obj) over (partition by hh.sql_id, hh.event order by hh.total_obj desc nulls last) total_top_obj,
+         dense_rank() over (partition by hh.sql_id order by hh.total_ev desc) topn_ev,
+         dense_rank() over (order by total_sess desc) topn
+  from (
+    select h.sql_id, h.wait_class, h.event, h.current_obj#, 
+           count(*) over (partition by h.sql_id) total_sess, 
+           count(*) over (partition by h.sql_id, h.event) total_ev, 
+           case when h.current_obj#>1 then count(*) over (partition by h.sql_id, h.current_obj#) else -1 end total_obj
+    from dba_hist_active_sess_history h
+    where h.instance_number=1
+      and h.session_state='WAITING'
+      and h.sql_id is not null
+      and h.sample_time between '&1' and '&2'
+  ) hh
+) hhh 
+where 1=1
+  and topn<=14
+--  and topn_ev<=5
+having 100*count(*)/hhh.total_sess>10  -- this wait event accounts for more than 10% of this SQL statement
+group by hhh.sql_id, hhh.wait_class, hhh.event, hhh.total_sess, hhh.top_obj, hhh.total_top_obj, hhh.topn_ev, hhh.topn
+)
+select m.sql_id,
+       dbms_lob.substr(t.sql_text,40,1) sql_text,
+       m.percentage,
+       m.wait_class,
+       m.event,
+--       m.top_obj,
+       m.top_obj_pct,
+       o.object_name top_object,
+       o.object_type top_obj_type,
+       m.total_samples
+from master m, dba_hist_sqltext t, dba_objects o
+where m.top_obj=o.object_id(+) and m.sql_id=t.sql_id
+order by m.topn, m.percentage desc
+/
+