3

我有一个包含时间戳值的表，我想将这些值中的每一个四舍五入到最接近的秒，但我无法让它正常工作。

到目前为止我的测试数据和方法：

with v_data as
 (select to_timestamp('2012-12-10 10:49:30.00000000',
                      'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
         to_timestamp('2012-12-10 10:49:30',
                      'YYYY-MM-DD HH24:mi:ss') expected
    from dual
  union all
  select to_timestamp('2012-12-10 10:49:30.46300000',
                      'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
         to_timestamp('2012-12-10 10:49:30',
                      'YYYY-MM-DD HH24:mi:ss') expected
    from dual
  union all
  select to_timestamp('2012-12-10 10:49:30.50000000',
                      'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
         to_timestamp('2012-12-10 10:49:31',
                      'YYYY-MM-DD HH24:mi:ss') expected
    from dual
  union all
  select to_timestamp('2012-12-10 10:49:30.56300000',
                      'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
         to_timestamp('2012-12-10 10:49:31',
                      'YYYY-MM-DD HH24:mi:ss') expected

    from dual
  union all
  select to_timestamp('2012-12-10 10:49:30.99999999',
                      'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
         to_timestamp('2012-12-10 10:49:31',
                      'YYYY-MM-DD HH24:mi:ss') expected
    from dual)
select v1.base_val,
       v1.expected,
       v1.base_val + (0.5 / 86400) solution_round,
       cast(v1.base_val as date) as solution_cast,
       extract(second from v1.base_val) - trunc(extract(second from v1.base_val)) fractional_seconds,
       v1.base_val -
       (extract(second from v1.base_val) - trunc(extract(second from v1.base_val))) / 86400 solution_add
  from v_data v1

我所有的解决方案都有一个缺陷：

  • solution_round 总是四舍五入
  • solution_cast 适用于 11gR1，但在 11gR2 中，它总是向下舍入（原因：Oracle 改变了行为 - 它现在截断而不是四舍五入，请参阅https://forums.oracle.com/forums/thread.jspa?threadID=2242066）
  • solution_add 返回最后三行的 10:49:29 而不是 10:49:31

我想solution_add 应该可以工作，我只是犯了一些愚蠢的错误:-)

编辑：

Ben 的解决方案（见下文）对我有用，但依赖 to_char(timestamp, 'FF') 似乎很危险——返回的位数取决于时间戳的定义。

我正在使用 to_char(timestamp, 'FF3') 代替，它似乎可靠地返回毫秒。

4

5 回答 5

5

我的首选方法是使用 CASE 语句，并且您可以将小数秒转换为数字，即：

select base_val, expected
     , to_timestamp(to_char(base_val,'YYYY-MM-DD HH24:mi:ss'),'YYYY-MM-DD HH24:mi:ss')
        + case when to_number(to_char(base_val, 'FF8')) >= 500000000 
                    then interval '1' second
               else interval '0' second
          end as solution_add
  from v_data

这将删除小数秒。然后计算出您的 TIMESTAMP 的小数秒部分是否为 0.5 秒或更多。如果是，则添加第二个，否则不要。

我发现它更清晰，更容易理解发生了什么。它返回以下内容：

with v_data as
 (select to_timestamp('2012-12-10 10:49:30.00000000',
                      'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
         to_timestamp('2012-12-10 10:49:30',
                      'YYYY-MM-DD HH24:mi:ss') expected
    from dual
  union all
  select to_timestamp('2012-12-10 10:49:30.46300000',
                      'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
         to_timestamp('2012-12-10 10:49:30',
                      'YYYY-MM-DD HH24:mi:ss') expected
    from dual
  union all
  select to_timestamp('2012-12-10 10:49:30.50000000',
                      'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
         to_timestamp('2012-12-10 10:49:31',
                      'YYYY-MM-DD HH24:mi:ss') expected
    from dual
  union all
  select to_timestamp('2012-12-10 10:49:30.56300000',
                      'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
         to_timestamp('2012-12-10 10:49:31',
                      'YYYY-MM-DD HH24:mi:ss') expected
    from dual
  union all
  select to_timestamp('2012-12-10 10:49:30.99999999',
                      'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
         to_timestamp('2012-12-10 10:49:31',
                      'YYYY-MM-DD HH24:mi:ss') expected
    from dual
         )
select base_val, expected
     , to_timestamp(to_char(base_val, 'YYYY-MM-DD HH24:mi:ss'), 'YYYY-MM-DD HH24:mi:ss')
        + case when to_number(to_char(base_val, 'FF8')) >= 500000000 
                    then interval '1' second
               else interval '0' second
          end as solution_add
  from v_data;

BASE_VAL                     EXPECTED                     SOLUTION_ADD
---------------------------- ---------------------------- ----------------------------
10-DEC-12 10.49.30.000000000 10-DEC-12 10.49.30.000000000 10-DEC-12 10.49.30.000000000
10-DEC-12 10.49.30.463000000 10-DEC-12 10.49.30.000000000 10-DEC-12 10.49.30.000000000
10-DEC-12 10.49.30.500000000 10-DEC-12 10.49.31.000000000 10-DEC-12 10.49.31.000000000
10-DEC-12 10.49.30.563000000 10-DEC-12 10.49.31.000000000 10-DEC-12 10.49.31.000000000
10-DEC-12 10.49.30.999999990 10-DEC-12 10.49.31.000000000 10-DEC-12 10.49.31.000000000
于 2012-12-10T16:24:16.693 回答
3

您的最终方法有效（solution_add），它只是您使用的-而不是+。11g 的行为是由于一个错误修复（在 10g 及更低版本中，plsql 在使用 cast 时表现为“trunc”，而 SQL 表现为圆形。Oracle 认为 PLSQL 是正确的，并相应地更改了 11g。

即使用：

   v1.base_val +
   (extract(second from v1.base_val) - trunc(extract(second from v1.base_val))) / 86400 solution_add

虽然我可能会明确指定它以消除从时间戳到日期的隐式转换（避免狡猾的 cast()）

to_date(to_char(v1.base_val, 'dd-mm-yyyy hh24:mi:ss'), 'dd-mm-yyyy hh24:mi:ss')+
       (( extract(second from v1.base_val) - trunc(extract(second from v1.base_val))) / 86400)

例如：

SQL> select * from v$version;

BANNER
----------------------------------------------------------------
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bi
PL/SQL Release 10.2.0.4.0 - Production
CORE    10.2.0.4.0      Production
TNS for Linux: Version 10.2.0.4.0 - Production
NLSRTL Version 10.2.0.4.0 - Production

SQL> with v_data as
  2   (select to_timestamp('2012-12-10 10:49:30.00000000',
  3                        'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
  4           to_timestamp('2012-12-10 10:49:30',
  5                        'YYYY-MM-DD HH24:mi:ss') expected
  6      from dual
  7    union all
  8    select to_timestamp('2012-12-10 10:49:30.46300000',
  9                        'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
 10           to_timestamp('2012-12-10 10:49:30',
 11                        'YYYY-MM-DD HH24:mi:ss') expected
 12      from dual
 13    union all
 14    select to_timestamp('2012-12-10 10:49:30.50000000',
 15                        'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
 16           to_timestamp('2012-12-10 10:49:31',
 17                        'YYYY-MM-DD HH24:mi:ss') expected
 18      from dual
 19    union all
 20    select to_timestamp('2012-12-10 10:49:30.56300000',
 21                        'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
 22           to_timestamp('2012-12-10 10:49:31',
 23                        'YYYY-MM-DD HH24:mi:ss') expected
 24      from dual
 25    union all
 26    select to_timestamp('2012-12-10 10:49:30.99999999',
 27                        'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
 28           to_timestamp('2012-12-10 10:49:31',
 29                        'YYYY-MM-DD HH24:mi:ss') expected
 30      from dual)
 31  select v1.base_val,
 32         v1.expected,
 33         v1.base_val +
 34         (extract(second from v1.base_val) - trunc(extract(second from v1.base_val))) / 86400 solution_add,
 35         to_date(to_char(v1.base_val, 'dd-mm-yyyy hh24:mi:ss'), 'dd-mm-yyyy hh24:mi:ss')+
 36         (( extract(second from v1.base_val) - trunc(extract(second from v1.base_val))) / 86400) solution_add2
 37    from v_data v1;

BASE_VAL                  EXPECTED                  SOLUTION_ADD              SOLUTION_ADD2
------------------------- ------------------------- ------------------------- -------------------------
10-dec-12 10:49:30000     10-dec-12 10:49:30000     10-dec-2012 10:49:30      10-dec-2012 10:49:30
10-dec-12 10:49:30463     10-dec-12 10:49:30000     10-dec-2012 10:49:30      10-dec-2012 10:49:30
10-dec-12 10:49:30500     10-dec-12 10:49:31000     10-dec-2012 10:49:31      10-dec-2012 10:49:31
10-dec-12 10:49:30563     10-dec-12 10:49:31000     10-dec-2012 10:49:31      10-dec-2012 10:49:31
10-dec-12 10:49:30999     10-dec-12 10:49:31000     10-dec-2012 10:49:31      10-dec-2012 10:49:31




SQL> select * from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
PL/SQL Release 11.2.0.2.0 - Production
CORE    11.2.0.2.0      Production
TNS for Linux: Version 11.2.0.2.0 - Production
NLSRTL Version 11.2.0.2.0 - Production

SQL> with v_data as
  2   (select to_timestamp('2012-12-10 10:49:30.00000000',
  3                        'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
  4           to_timestamp('2012-12-10 10:49:30',
  5                        'YYYY-MM-DD HH24:mi:ss') expected
  6      from dual
  7    union all
  8    select to_timestamp('2012-12-10 10:49:30.46300000',
  9                        'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
 10           to_timestamp('2012-12-10 10:49:30',
 11                        'YYYY-MM-DD HH24:mi:ss') expected
 12      from dual
 13    union all
 14    select to_timestamp('2012-12-10 10:49:30.50000000',
 15                        'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
 16           to_timestamp('2012-12-10 10:49:31',
 17                        'YYYY-MM-DD HH24:mi:ss') expected
 18      from dual
 19    union all
 20    select to_timestamp('2012-12-10 10:49:30.56300000',
 21                        'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
 22           to_timestamp('2012-12-10 10:49:31',
 23                        'YYYY-MM-DD HH24:mi:ss') expected
 24      from dual
 25    union all
 26    select to_timestamp('2012-12-10 10:49:30.99999999',
 27                        'YYYY-MM-DD HH24:mi:ss.FF8') base_val,
 28           to_timestamp('2012-12-10 10:49:31',
 29                        'YYYY-MM-DD HH24:mi:ss') expected
 30      from dual)
 31  select v1.base_val,
 32         v1.expected,
 33         v1.base_val +
 34         (extract(second from v1.base_val) - trunc(extract(second from v1.base_val))) / 86400 solution_add,
 35         to_date(to_char(v1.base_val, 'dd-mm-yyyy hh24:mi:ss'), 'dd-mm-yyyy hh24:mi:ss')+
 36         (( extract(second from v1.base_val) - trunc(extract(second from v1.base_val))) / 86400) solution_add2
 37    from v_data v1;

BASE_VAL                  EXPECTED                  SOLUTION_ADD              SOLUTION_ADD2
------------------------- ------------------------- ------------------------- -------------------------
10-dec-12 10:49:30000     10-dec-12 10:49:30000     10-dec-12 10:49:30        10-dec-12 10:49:30
10-dec-12 10:49:30463     10-dec-12 10:49:30000     10-dec-12 10:49:30        10-dec-12 10:49:30
10-dec-12 10:49:30500     10-dec-12 10:49:31000     10-dec-12 10:49:31        10-dec-12 10:49:31
10-dec-12 10:49:30563     10-dec-12 10:49:31000     10-dec-12 10:49:31        10-dec-12 10:49:31
10-dec-12 10:49:30999     10-dec-12 10:49:31000     10-dec-12 10:49:31        10-dec-12 10:49:31
于 2012-12-10T15:31:55.267 回答
1

我对这个讨论非常非​​常晚，但万一有人搜索，这个问题有一个单行答案：

首先 CAST 到 TIMESTAMP(0) - 它没有小数秒，因此它们将被四舍五入。然后将结果转换为 DATE

alter session set nls_date_format='yyyy-mm-dd hh24:mi:ss';
with data as (select sys_extract_utc(localtimestamp) ts from dual)
select ts, cast(cast(ts as timestamp(0)) as date) dte
from data;
于 2018-09-20T11:42:41.563 回答
0

您是否尝试过转换 to_date 并在那时进行舍入？

http://www.java2s.com/Tutorial/Oracle/0260__Date-Timestamp-Functions/RoundingtotheNearestMinute.htm

然后，您应该能够转换为时间戳。

显然将第 3 行的“MI”更改为“SS”

---UPDATE---

转换为日期将四舍五入到最接近的秒，因为 DATE 数据类型的精度为秒，因此转换为日期，然后转换为时间戳：

to_timestamp(CAST('2012-12-10 10:49:30.99999999' AS DATE))

于 2012-12-10T14:42:30.790 回答
-1

这是 T-SQL（不确定它是否适用于 Oracle）

DECLARE @tblTime TABLE (ID INT, myTime DATETIME2);
INSERT INTO @tblTime SELECT 1, GETDATE()

SELECT  myTime
    , CONVERT( DATETIME2, CONVERT( VARCHAR, DATEADD( SECOND, CASE WHEN DATEPART( MS, myTime) >= 500 THEN 1 ELSE -1 END, myTime ), 20), 20 ) AS timeRounded
FROM    @tblTime
于 2012-12-10T14:49:00.340 回答