Calculate actual time (Out Date Time - In Date Time)

Question

Hi All
I am using Oracle 9i
I have a two column table
having date and time value in on of the column
data is look like this
Name Performed_Time
IN 30-MAR-2008 09:15
OUT 30-MAR-2008 11:30
IN 30-MAR-2008 12:00
OUT 30-MAR-2008 14:45
IN 30-MAR-2008 16:00
OUT 30-MAR-2008 18:21
No the problem is that
I need to calculate the actual time between every OUT and IN e.g OUT - IN (Out Time minus In Time)
wud anybody plz help me regarding this?
Thanks
Hassan

Answer 1

Nice one, but seems to be expensive.
SQL> set autotrace on
SQL> Select (dt_out - dt_in) * 24*60
  2        from (select flag, dt dt_in, lead(dt) over (order by dt) dt_out
  3                from t)
  4      where flag = 'IN';
(DT_OUT-DT_IN)*24*60
                 135
                 165
                 141
Execution Plan
Plan hash value: 3295878825
| Id  | Operation           | Name | Rows  | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT    |      |     6 |   126 |     4  (25)| 00:00:01 |
|*  1 |  VIEW               |      |     6 |   126 |     4  (25)| 00:00:01 |
|   2 |   WINDOW SORT       |      |     6 |    72 |     4  (25)| 00:00:01 |
|   3 |    TABLE ACCESS FULL| T    |     6 |    72 |     3   (0)| 00:00:01 |
Predicate Information (identified by operation id):
   1 - filter("FLAG"='IN')
Note
   - dynamic sampling used for this statement
Statistics
          4  recursive calls
          0  db block gets
         15  consistent gets
          0  physical reads
          0  redo size
        473  bytes sent via SQL*Net to client
        395  bytes received via SQL*Net from client
          2  SQL*Net roundtrips to/from client
          1  sorts (memory)
          0  sorts (disk)
          3  rows processed
SQL>
SQL>
SQL>   Select ins.dt as in_time, outs.dt as out_time, (outs.dt - ins.dt)*24 as time_in
  2      from (
  3           select flag, dt, row_number() over (order by dt) as rn
  4           from t
  5           where flag = 'IN'
  6          ) ins
  7          LEFT OUTER JOIN
  8          (select flag, dt, row_number() over (order by dt) as rn
  9           from t
10           where flag = 'OUT'
11          ) outs
12          ON (ins.rn = outs.rn);
IN_TIME           OUT_TIME             TIME_IN
30-MAR-2008 09:15 30-MAR-2008 11:30       2.25
30-MAR-2008 12:00 30-MAR-2008 14:45       2.75
30-MAR-2008 16:00 30-MAR-2008 18:21       2.35
Execution Plan
Plan hash value: 3072654067
| Id  | Operation            | Name | Rows  | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT     |      |     3 |   138 |     9  (34)| 00:00:01 |
|*  1 |  HASH JOIN OUTER     |      |     3 |   138 |     9  (34)| 00:00:01 |
|   2 |   VIEW               |      |     3 |    72 |     4  (25)| 00:00:01 |
|   3 |    WINDOW SORT       |      |     3 |    45 |     4  (25)| 00:00:01 |
|*  4 |     TABLE ACCESS FULL| T    |     3 |    45 |     3   (0)| 00:00:01 |
|   5 |   VIEW               |      |     3 |    66 |     4  (25)| 00:00:01 |
|   6 |    WINDOW SORT       |      |     3 |    36 |     4  (25)| 00:00:01 |
|*  7 |     TABLE ACCESS FULL| T    |     3 |    36 |     3   (0)| 00:00:01 |
Predicate Information (identified by operation id):
   1 - access("INS"."RN"="OUTS"."RN"(+))
   4 - filter("FLAG"='IN')
   7 - filter("FLAG"='OUT')
Note
   - dynamic sampling used for this statement
Statistics
          7  recursive calls
          0  db block gets
         30  consistent gets
          0  physical reads
          0  redo size
        623  bytes sent via SQL*Net to client
        395  bytes received via SQL*Net from client
          2  SQL*Net roundtrips to/from client
          2  sorts (memory)
          0  sorts (disk)
          3  rows processed
SQL>