# How can I compare datetimes?

**URL:** <https://www.ruby-forum.com/t/how-can-i-compare-datetimes/132583>\
**Category:** Rails\
**Created:** [March 21, 2008, 5:44pm UTC](https://www.ruby-forum.com/t/how-can-i-compare-datetimes/132583 "2008-03-21T17:44:07Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![captaffy](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/f04885/32.png) [@captaffy](https://www.ruby-forum.com/u/captaffy)\
**Post date:** [March 21, 2008, 5:44pm UTC](https://www.ruby-forum.com/t/how-can-i-compare-datetimes/132583/1 "2008-03-21T17:44:07Z")

</div>

I want to generate pdfs from my database, from tickets. This pdfs are  
meant to be generated and saved every Friday at an specific hour. How  
can I do that?

---

<div class="post-metadata">

**Author:** ![captaffy](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/f04885/32.png) [@captaffy](https://www.ruby-forum.com/u/captaffy)\
**Post date:** [March 22, 2008, 8:39pm UTC](https://www.ruby-forum.com/t/how-can-i-compare-datetimes/132583/2 "2008-03-22T20:39:56Z")

</div>

John S. wrote:

> I want to generate pdfs from my database, from tickets. This pdfs are  
> meant to be generated and saved every Friday at an specific hour. How  
> can I do that?

Create a cron job to do that?

I suppose with every rails request you could add something like  
if Time.now \> last\_time\_updated  
or something

look into the Ruby Date class and Time class.