Re: [HACKERS] [PATCH] Fix for documentation of timestamp type

On Mon, Dec 12, 2016 at 8:50 AM, Aleksander Alekseev
<a.alekseev@postgrespro.ru> wrote:
> I suggest to rewrite the documentation a bit to make it more clear that
> by default timestamp is stored in microseconds. Corresponding patch is
> attached.

I find this a bit unclear, because the revised text kind of jumps back
and forth between the floating-point and integer formats.  Perhaps
something like this:
   When <type>timestamp</> values are stored as eight-byte integers   (currently the default), microsecond precision is
availableover   the full range of values.  In this case, the internal representation is the   number of microseconds
beforeor after midnight 2000-01-01.   When <type>timestamp</> values are   stored as double precision floating-point
numbersinstead (a   deprecated compile-time option), the internal representation is the number   of seconds before or
aftermidnight 2000-01-01.  With this representation,   the effective limit of precision might be less than 6; in
practice,  microsecond precision is achieved for dates within a few   years of 2000-01-01, but the precision degrades
fordates further   away. Note that using floating-point datetimes allows a larger   range of <type>timestamp</type>
valuesto be represented than   shown above: from 4713 BC up to 5874897 AD.
 

-- 
Robert Haas
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