SET TERM ON HEA ON LIN 2490 PAGES 100 TAB OFF FEED OFF ECHO OFF VER OFF TRIMS ON TRIM ON TI OFF TIMI OFF LONG 240000 LONGC 2400 NUM 20 SERVEROUT OFF;

ALTER SESSION SET NLS_TIMESTAMP_FORMAT = 'YYYY-MM-DD"T"HH24:MI:SS.FF3';

--

COL day FOR A10;

COL sample_time FOR A25;

COL active_sessions FOR 999,990 HEA 'SESSIONS';

COL max_sessions FOR A4 HEA 'MAX';

COL peak FOR A5 HEA 'PEAK';

COL graph FOR A200 HEA 'GRAPH';

--

BREAK ON day SKIP PAGE DUPL;

--

WITH

cpu_cores AS (

SELECT /*+ MATERIALIZE NO_MERGE */value FROM v$osstat WHERE stat_name = 'NUM_CPU_CORES' AND ROWNUM >= 1 /* MATERIALIZE */

),

active_sessions_time_series AS (

SELECT /*+ MATERIALIZE NO_MERGE */

sample_time,

COUNT(*) AS active_sessions

FROM dba_hist_active_sess_history

WHERE ROWNUM >= 1 /* MATERIALIZE */

GROUP BY

sample_time

)

-- https://blog.dbi-services.com/oracle-row-pattern/

SELECT TO_CHAR(sample_time, 'YYYY-MM-DD') AS day, sample_time, active_sessions,

CASE WHEN active_sessions = MAX(active_sessions) OVER (PARTITION BY TO_CHAR(sample_time, 'YYYY-MM-DD')) THEN 'MAX' END AS max_sessions,

CASE WHEN active_sessions = peak_active_sessions THEN 'PEAK' END AS peak,

LPAD('*', active_sessions / 100, '*') AS graph

FROM cpu_cores, active_sessions_time_series

MATCH_RECOGNIZE (

/* PARTITION BY xxx */ ORDER BY sample_time

MEASURES

MATCH_NUMBER() AS peak_num,

LAST(GOINGUP.sample_time) AS peak_time,

LAST(GOINGUP.active_sessions) AS peak_active_sessions

ALL ROWS PER MATCH

PATTERN (GOINGUP+ GOINGDOWN+)

DEFINE

GOINGUP AS (GOINGUP.active_sessions > PREV(GOINGUP.active_sessions)),

GOINGDOWN AS (GOINGDOWN.active_sessions < PREV(GOINGDOWN.active_sessions))

)

WHERE active_sessions > 10 * cpu_cores.value

ORDER BY sample_time

/