Re: date ranges in where

On May 6, 2009, at 2:59 PM, Adrian Klaver wrote:

> On Wednesday 06 May 2009 2:51:08 pm Erik Jones wrote:
>> On May 6, 2009, at 2:48 PM, Miguel Miranda wrote:
>>> Well, i tried all your sugestions, and i found some funny issues, i
>>> use the query to count exactly in a day by day basis, and running
>>> the query with
>>>
>>> WHERE lastlogin >= '2009-05-01' AND lastlogin < '2009-05-03'
>>>
>>> OR
>>>
>>> WHERE lastlogin >= 'X' AND lastlogin <= 'Y' + '1 day'::interval
>>>
>>>
>>> it includes the 0 hours of day 3:
>>>
>>> 05-02-2009 12:00:00 AM
>>
>> No, 05-02-2009 12:00:00 AM is the midnight point between 2009-05-01
>> and 2009-05-02.
>
> The problem being that midnight is both the end of one day and the
> start of
> another.

Not from perspective of the database which has no concept of
midnight.  My point above was simply that 2009-05-02 12:00:00 AM is
the start of the 2nd, not the 3rd.

Erik Jones, Database Administrator
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