SQL:Unterschied zwischen zwei Daten

Es ist nicht so schwierig, die Anzahl der Tage ohne Samstag und Sonntag zu ermitteln, Sie finden mehrere Lösungen dafür bei SO.

Die Berücksichtigung von Feiertagen ist schwieriger. Eine Lösung ist die Verwendung des Oracle SCHEDULER . Standardmäßig wird dies für SCHEDULER JOBS verwendet , ich sehe jedoch keinen Grund, es nicht für andere Zwecke zu verwenden.

Das größte Problem ist der Ostertag, siehe hier:Computus. Ich denke, der effizienteste Weg ist, die Daten fest zu codieren und manuell zu pflegen.

BEGIN
    DBMS_SCHEDULER.CREATE_SCHEDULE('New_Year', repeat_interval => 'FREQ=YEARLY;BYDATE=0101');

    DBMS_SCHEDULER.CREATE_SCHEDULE('Easter_Sunday',  repeat_interval => 'FREQ=YEARLY;BYDATE=20150405,    20160327,    20170416,    20170416,    20180401,    20190421,    20200412', comments => 'Hard coded till 2020');
    DBMS_SCHEDULER.CREATE_SCHEDULE('Good_Friday',    repeat_interval => 'FREQ=YEARLY;BYDATE=20150405-2D, 20160327-2D, 20170416-2D, 20170416-2D, 20180401-2D, 20190421-2D, 20200412-2D');
    DBMS_SCHEDULER.CREATE_SCHEDULE('Easter_Monday',   repeat_interval => 'FREQ=YEARLY;BYDATE=20150405+1D, 20160327+1D, 20170416+1D, 20170416+1D, 20180401+1D, 20190421+1D, 20200412+1D');
    DBMS_SCHEDULER.CREATE_SCHEDULE('Ascension_Day',   repeat_interval => 'FREQ=YEARLY;BYDATE=20150405+39D,20160327+39D,20170416+39D,20170416+39D,20180401+39D,20190421+39D,20200412+39D');
    DBMS_SCHEDULER.CREATE_SCHEDULE('Pentecost_Monday', repeat_interval => 'FREQ=YEARLY;BYDATE=20150405+50D,20160327+50D,20170416+50D,20170416+50D,20180401+50D,20190421+50D,20200412+50D');

    DBMS_SCHEDULER.CREATE_SCHEDULE('Repentance_and_Prayer', repeat_interval => 'FREQ=DAILY;BYDATE=1122-SPAN:7D;BYDAY=WED', 
        comments => 'Wednesday before November 23th, Buss- und Bettag');
    -- alternative solution: 
    --DBMS_SCHEDULER.CREATE_SCHEDULE('Repentance_and_Prayer', repeat_interval => 'FREQ=MONTHLY;BYMONTH=NOV;BYDAY=3 WED', 
    --    comments => '3rd Wednesday in November');

    DBMS_SCHEDULER.CREATE_SCHEDULE('Labor_Day', repeat_interval => 'FREQ=YEARLY;BYDATE=0501');
    DBMS_SCHEDULER.CREATE_SCHEDULE('German_Unity_Day', repeat_interval => 'FREQ=YEARLY;BYDATE=1003');
    DBMS_SCHEDULER.CREATE_SCHEDULE('Christmas', repeat_interval => 'FREQ=YEARLY;BYDATE=1225+SPAN:2D');

    DBMS_SCHEDULER.CREATE_SCHEDULE('Christian_Celebration_Days', repeat_interval => 'FREQ=DAILY;INTERSECT=Easter_Sunday,Good_Friday,Easter_Monday,Ascension_Day,Pentecost_Monday,Repentance_and_Prayer,Christmas');
    -- alternative solution: 
    -- DBMS_SCHEDULER.CREATE_SCHEDULE('Christian_Celebration_Days', repeat_interval => 'FREQ=Good_Friday;BYDAY=1 MON, 6 THU,8 MON');
    DBMS_SCHEDULER.CREATE_SCHEDULE('Political_Holidays', repeat_interval => 'FREQ=DAILY;INTERSECT=New_Year,Labor_Day,German_Unity_Day');


END;
/

Siehe Syntax für Kalender hier:Kalendersyntax

Dann können Sie die Zeitpläne wie folgt verwenden:

CREATE OR REPLACE FUNCTION DateDiff(end_date IN TIMESTAMP) RETURN INTEGER AS
    next_run_date TIMESTAMP := TRUNC(SYSTIMESTAMP);
    res INTEGER := 0;
BEGIN
    IF end_date > SYSTIMESTAMP THEN
        LOOP
            DBMS_SCHEDULER.EVALUATE_CALENDAR_STRING('FREQ=DAILY;INTERVAL=1;BYDAY=MON,TUE,WED,THU,FRI; EXCLUDE=Christian_Celebration_Days,Political_Holidays', NULL, next_run_date, next_run_date);
            EXIT WHEN next_run_date >= end_date;
            res := res + 1;
        END LOOP;
        RETURN res;
    ELSE
        RAISE VALUE_ERROR;
    END IF;     
END;

SELECT DateDiff(TO_DATE('04/10/2015','mm/dd/yyyy')) AS Differenz FROM DUAL;

Die nächsten 20 Feiertage zum Testen ausgeben:

DECLARE
    next_run_date TIMESTAMP;
BEGIN
    FOR i IN 1..20 LOOP
        DBMS_SCHEDULER.EVALUATE_CALENDAR_STRING('FREQ=DAILY;INTERSECT='Christian_Celebration_Days,Political_Holidays', NULL, next_run_date, next_run_date);
        DBMS_OUTPUT.PUT_LINE(next_run_date);
    END LOOP;
END;

Aktualisieren

Ich habe sogar eine kompaktere Version gefunden:

BEGIN
    -- Start with first celebration day (good Friday), all dependent celebration days have to be after this day for proper calculation of schedule
    DBMS_SCHEDULER.CREATE_SCHEDULE('GOOD_FRIDAY', repeat_interval => 'FREQ=YEARLY;BYDATE=20100402,20110422,20120406,20130329,20140418,20150403,20160325,20170414,20180330,20190419,20200410,20210402,20220410,20230407,20240329,20250418,20260403,20270326,20280414,20290330,20300419', comments => 'Hard coded 2010 to 2030');
    -- Easter Sunday can be skipped for list of holidays, otherwise 'FREQ=Good_Friday;BYDAY=1 SUN+SPAN:2D'
    DBMS_SCHEDULER.CREATE_SCHEDULE('EASTER_MONDAY', repeat_interval => 'FREQ=Good_Friday;BYDAY=1 MON', comments => '1st Monday after Good Friday'
    DBMS_SCHEDULER.CREATE_SCHEDULE('ASCENSION_DAY', repeat_interval => 'FREQ=Good_Friday;BYDAY=6 THU', comments => '6th Thursday after Good Friday (40 days after Easter)');
    -- Pentecost Sunday can be skipped for list of holidays, otherwise 'FREQ=Good_Friday;BYDAY=8 SUN+SPAN:2D'
    DBMS_SCHEDULER.CREATE_SCHEDULE('PENTECOST_MONDAY', repeat_interval => 'FREQ=Good_Friday;BYDAY=8 MON', comments => '8th Monday after Good Friday (50 days after Easter)');
    DBMS_SCHEDULER.CREATE_SCHEDULE('EASTER_RELATED_DAYS', repeat_interval => 'FREQ=Good_Friday;BYDAY=1 MON, 6 THU,8 MON'
END;