oracle - 按小时聚合毫秒

Question

我有一个带有时间戳（dd.mm.yyyy hh24:mi:ss）和持续时间（以毫秒为单位）的 tbl

如何按小时汇总这些持续时间？它应该告诉我每小时的 AVG 毫秒数。

样本：

Timestamp              Duration
10.10.2010 12:30:20    200
10.10.2010 12:59:10    400

输出：

Timestamp              Duration
10.10.2010 12:00:00    300

Answer 1

尝试这样的事情：

SELECT TO_CHAR("Date", 'HH24'), AVG("Duration") FROM "Table" GROUP BY TO_CHAR("Date", 'HH24')

Answer 2

您正在寻找 ROUND 和 AVG

WITH DATASET
    AS (SELECT TO_TIMESTAMP_TZ ( '11/8/2013 1:16:22', 'MM/DD/YYYY HH24:MI:SS' ) AS TS,
               200 AS DURATION
        FROM DUAL
        UNION ALL
        SELECT TO_TIMESTAMP_TZ ( '11/8/2013 1:16:22', 'MM/DD/YYYY HH24:MI:SS' ) AS TS,
               100 AS DURATION
        FROM DUAL
        UNION ALL
        SELECT TO_TIMESTAMP_TZ ( '11/8/2013 2:16:22', 'MM/DD/YYYY HH24:MI:SS' ) AS TS,
               300 AS DURATION
        FROM DUAL
        UNION ALL
        SELECT TO_TIMESTAMP_TZ ( '11/8/2013 3:16:22', 'MM/DD/YYYY HH24:MI:SS' ) AS TS,
               500 AS DURATION
        FROM DUAL
        UNION ALL
        SELECT TO_TIMESTAMP_TZ ( '11/8/2013 4:16:22', 'MM/DD/YYYY HH24:MI:SS' ) AS TS,
               600 AS DURATION
        FROM DUAL
        UNION ALL
        SELECT TO_TIMESTAMP_TZ ( '11/8/2013 4:16:22', 'MM/DD/YYYY HH24:MI:SS' ) AS TS,
               700 AS DURATION
        FROM DUAL)
SELECT ROUND ( TS, 'Hh24' ) AS TIMESTAMP_VAL,
       AVG ( DURATION ) AS DURATION
FROM
      DATASET
GROUP BY
      ROUND ( TS, 'Hh24' )
ORDER BY
      TIMESTAMP_VAL;

注意： extract(hour from systimestamp) 将减去时区偏移量