SPO sql_performance_changed.txt;
DEF days_of_history_accessed = ’31’;
DEF captured_at_least_x_times = ‘1’;
DEF captured_at_least_x_days_apart = ‘1’;
DEF med_elap_microsecs_threshold = ‘1e4’;
DEF min_slope_threshold = ‘0.1’;
DEF max_num_rows = ’20’;
SET lin 500 ver OFF;
set pagesize 100;
set feedback off;
COL row_n FOR A2 HEA ‘#’;
COL med_secs_per_exec HEA ‘Median Secs|Per Exec’;
COL std_secs_per_exec HEA ‘Std Dev Secs|Per Exec’;
COL avg_secs_per_exec HEA ‘Avg Secs|Per Exec’;
COL min_secs_per_exec HEA ‘Min Secs|Per Exec’;
COL max_secs_per_exec HEA ‘Max Secs|Per Exec’;
COL plans FOR 9999;
COL sql_text_80 FOR A80;
PRO SQL Statements with “Elapsed Time per Execution” changing over time
WITH
per_time AS (
SELECT h.dbid,
h.sql_id,
SYSDATE – CAST(s.end_interval_time AS DATE) days_ago,
SUM(h.elapsed_time_total) / SUM(h.executions_total) time_per_exec
FROM dba_hist_sqlstat h,
dba_hist_snapshot s
WHERE h.executions_total > 0
AND s.snap_id = h.snap_id
AND s.dbid = h.dbid
AND s.instance_number = h.instance_number
AND CAST(s.end_interval_time AS DATE) > SYSDATE – &&days_of_history_accessed.
GROUP BY
h.dbid,
h.sql_id,
SYSDATE – CAST(s.end_interval_time AS DATE)
),
avg_time AS (
SELECT dbid,
sql_id,
MEDIAN(time_per_exec) med_time_per_exec,
STDDEV(time_per_exec) std_time_per_exec,
AVG(time_per_exec) avg_time_per_exec,
MIN(time_per_exec) min_time_per_exec,
MAX(time_per_exec) max_time_per_exec
FROM per_time
GROUP BY
dbid,
sql_id
HAVING COUNT(*) >= &&captured_at_least_x_times.
AND MAX(days_ago) – MIN(days_ago) >= &&captured_at_least_x_days_apart.
AND MEDIAN(time_per_exec) > &&med_elap_microsecs_threshold.
),
time_over_median AS (
SELECT h.dbid,
h.sql_id,
h.days_ago,
(h.time_per_exec / a.med_time_per_exec) time_per_exec_over_med,
a.med_time_per_exec,
a.std_time_per_exec,
a.avg_time_per_exec,
a.min_time_per_exec,
a.max_time_per_exec
FROM per_time h, avg_time a
WHERE a.sql_id = h.sql_id
),
ranked AS (
SELECT RANK () OVER (ORDER BY ABS(REGR_SLOPE(t.time_per_exec_over_med, t.days_ago)) DESC) rank_num,
t.dbid,
t.sql_id,
CASE WHEN REGR_SLOPE(t.time_per_exec_over_med, t.days_ago) > 0 THEN ‘IMPROVING’ ELSE ‘REGRESSING’ END change,
ROUND(REGR_SLOPE(t.time_per_exec_over_med, t.days_ago), 3) slope,
ROUND(AVG(t.med_time_per_exec)/1e6, 3) med_secs_per_exec,
ROUND(AVG(t.std_time_per_exec)/1e6, 3) std_secs_per_exec,
ROUND(AVG(t.avg_time_per_exec)/1e6, 3) avg_secs_per_exec,
ROUND(MIN(t.min_time_per_exec)/1e6, 3) min_secs_per_exec,
ROUND(MAX(t.max_time_per_exec)/1e6, 3) max_secs_per_exec
FROM time_over_median t
GROUP BY
t.dbid,
t.sql_id
HAVING ABS(REGR_SLOPE(t.time_per_exec_over_med, t.days_ago)) > &&min_slope_threshold.
)
SELECT LPAD(ROWNUM, 2) row_n,
r.sql_id,
r.change,
r.slope slope,
r.med_secs_per_exec med_secs_per_exec,
r.std_secs_per_exec std_secs_per_exec,
r.avg_secs_per_exec avg_secs_per_exec,
r.min_secs_per_exec min_secs_per_exec,
r.max_secs_per_exec max_secs_per_exec,
— substr(TO_CHAR(r.slope, ‘990.000MI’),1,8) slope,
— TO_CHAR(r.med_secs_per_exec, ‘999,990.000’) med_secs_per_exec,
— TO_CHAR(r.std_secs_per_exec, ‘999,990.000’) std_secs_per_exec,
— TO_CHAR(r.avg_secs_per_exec, ‘999,990.000’) avg_secs_per_exec,
— TO_CHAR(r.min_secs_per_exec, ‘999,990.000’) min_secs_per_exec,
— TO_CHAR(r.max_secs_per_exec, ‘999,990.000’) max_secs_per_exec,
(SELECT COUNT(DISTINCT p.plan_hash_value) FROM dba_hist_sql_plan p WHERE p.dbid = r.dbid AND p.sql_id = r.sql_id) plans,
REPLACE((SELECT DBMS_LOB.SUBSTR(s.sql_text, 80) FROM dba_hist_sqltext s WHERE s.dbid = r.dbid AND s.sql_id = r.sql_id), CHR(10)) sql_text_80
FROM ranked r
WHERE r.rank_num <= &&max_num_rows.
and r.change not in (‘IMPROVING’)
ORDER BY
r.rank_num
/
SPO OFF;
