"Hiromichi Nakajima" <hirolin7@yahoo.co.jp> writes:
> I execute sql below:
> INSERT INTO A_TBL ( OPE_DATE) VALUES ( '2009-06-15 18:29:58.156')
> and show value with sql below:
> select TO_CHAR ( OP_DATE, 'YYYY-MM-DD HH24:MI:SS.MS.US')
> It must show as '2009-06-15 18:29:58.156.156000'
> but sometimes '2009-06-15 18:29:58.156.155999'
> Is it bug?
No, it's an inherent consequence of the fact that floating-point
timestamps aren't infinitely precise.
> This doesn't occur on 8.2.4.
The 8.2 coding had a different set of problems :-(
http://archives.postgresql.org/pgsql-bugs/2007-02/msg00090.php
regards, tom lane