Re: Inputting relative datetimes

On 27 August 2011 14:29, Jeff MacDonald <jam(at)zoidtechnologies(dot)com> wrote:
> Greetings,
>
> On Thursday, August 25, 2011 05:39:09 AM Dean Rasheed wrote:
>> As background, I have an app that accepts user text input and casts it
>> to a timestamp in order to produce reports. I use PostgreSQL's
>> timestamp input conversion for this, since it gives a lot of
>> flexibility, and can parse pretty much anything the users throw at it.
>>
>> It is also handy that it recognizes special case values like "now",
>> "today", "tomorrow" and "yesterday". However, I can't see any way of
>> entering more general relative timestamps like "5 days ago" or "2
>> hours from now".
>>
>
> Years ago I wrapped 'getdate.y' from the CVS source code and made it into a
> python extension. It handles "+2 hours" or "next week", etc. I don't know much
> of anything about making pg contrib modules, but it should not be hard to do.
> The way it works is you pass in a string and it returns the unix timestamp.
>
> [...snipped...]

That sounds like a pretty good approach, and a contrib module might
well be the way to go.

I'm not sure how best to handle timezones though, since it's
hard-coded list probably won't match the timezones PostgreSQL knows
about. Maybe that doesn't matter, I'm not sure.

Regards,
Dean