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下面的查询按小时输出数据库中所有表的“逻辑读取”。每个 snap_id 在一小时的时间范围内。

SELECT
    a.snap_id,
    e.begin_interval_time,
    e.end_interval_time,
    owner               as schema,
    object_name         AS table_name,
    logical_reads_delta as logical_reads_per_table
FROM
    dba_hist_seg_stat     a,
    dba_hist_seg_stat_obj b,
    dba_hist_sqlstat      c,
    dba_hist_snapshot     e
WHERE
        owner      !=  'SYS'
    and owner      !=  'SYSTEM'
    and a.snap_id   =  c.snap_id
    and c.snap_id   =  e.snap_id
    AND a.obj#      =  b.obj#
    AND a.dataobj#  =  b.dataobj#
    AND object_type = 'TABLE'
ORDER BY
    a.snap_id;

输出：

snap_id begin_interval_time       end_interval_time         schema table_name        logical_reads_per_table
------- ------------------------- ------------------------- ------ ----------------- -----------------------
8414    06/28/2012 7:00:11.006 AM 06/28/2012 8:00:16.540 AM WV90   WVT_WVPERFORATION 50288
8414    06/28/2012 7:00:11.006 AM 06/28/2012 8:00:16.540 AM WV90   WVT_WVPERFORATION 50288
8414    06/28/2012 7:00:11.006 AM 06/28/2012 8:00:16.540 AM WV90   WVT_WVPERFORATION 50288
8415    06/28/2012 8:00:16.540 AM 06/28/2012 9:00:21.516 AM EG     USER_GROUP_LIST   105328
8415    06/28/2012 8:00:16.540 AM 06/28/2012 9:00:21.516 AM EG     USER_GROUP_LIST   105328

我认为存在重复，因为每个表都有唯一的 SQL_ID（没有显示）。

我需要做一个左连接（我认为）和分组以获得我真正想要的指定输出。

我希望输出是这样的......

SNAP_ID | BEGIN_INTERVAL_TIME | END_INTERVAL_TIME ->>> OWNER | OBJECT_NAME | LOGICAL_READS_DELTA (logical reads in the time frame)

想法？

4

1 回答 1

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您可以尝试使用DISTINCT关键字删除重复项。

SELECT DISTINCT 
      a.snap_id, 
      e.begin_interval_time, 
      e.end_interval_time, 
      owner as schema, 
      object_name AS table_name, 
      logical_reads_delta as logical_reads_per_table
FROM  dba_hist_seg_stat a, 
      dba_hist_seg_stat_obj b, 
      dba_hist_sqlstat c, 
      dba_hist_snapshot e
WHERE owner != 'SYS'
      and owner!= 'SYSTEM'
      and a.snap_id=c.snap_id
      and c.snap_id=e.snap_id
      AND a.obj# = b.obj#
      AND a.dataobj# = b.dataobj#
      AND object_type = 'TABLE'
ORDER BY a.snap_id;`
于 2012-07-05T23:25:47.950 回答