# Checking date **URL:** \ **Category:** Rails\ **Created:** [April 21, 2006, 12:29am UTC](https://www.ruby-forum.com/t/checking-date/94106 "2006-04-21T00:29:48Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![SIX-S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/977dab/32.png) [@SIX-S](https://www.ruby-forum.com/u/SIX-S)\ **Post date:** [April 21, 2006, 12:29am UTC](https://www.ruby-forum.com/t/checking-date/94106/1 "2006-04-21T00:29:48Z")
Radrails created a field for date ``` <%= product.date_available.strftime("%y-%m-%d") %> ``` What does this mean? Should the definition be date or datetime? I tried both and no results Jim ---
**Author:** ![SIX-S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/977dab/32.png) [@SIX-S](https://www.ruby-forum.com/u/SIX-S)\ **Post date:** [April 21, 2006, 12:55am UTC](https://www.ruby-forum.com/t/checking-date/94106/2 "2006-04-21T00:55:22Z")
SIX-S wrote: > Radrails created a field for date > \<%= product.date\_available.strftime(“%y-%m-%d”) %\> > What does this mean? > That will convert the date “date\_available” into a string with the > format > yy-mm-dd as described here: > [Programming Ruby: The Pragmatic Programmer's Guide](http://www.ruby-doc.org/docs/ProgrammingRuby/html/ref_c_time.html#Time.strftime) > Should the definition be date or datetime? I tried both and no results Not quite sure what you’re asking here. Mark ---
**Author:** ![SIX-S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/977dab/32.png) [@SIX-S](https://www.ruby-forum.com/u/SIX-S)\ **Post date:** [April 21, 2006, 4:36am UTC](https://www.ruby-forum.com/t/checking-date/94106/3 "2006-04-21T04:36:37Z")
Thanks for answering my question. I dont know where the name " “strftime” originates I described the date\_available field in the table products(from tutorial “depot”) as type datetime. I changed the table type of date\_available as “date” when I had the error when running the program “list .rhtml” in my browser Firefox. JIm ----- Original Message ----- From: “Mark P.” [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) To: [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) Sent: Thursday, April 20, 2006 4:55 PM Subject: [Rails] Re: checking date ---
**Author:** ![SIX-S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/977dab/32.png) [@SIX-S](https://www.ruby-forum.com/u/SIX-S)\ **Post date:** [April 21, 2006, 1:04pm UTC](https://www.ruby-forum.com/t/checking-date/94106/4 "2006-04-21T13:04:05Z")
SIX-S wrote: > Thanks for answering my question. > I dont know where the name " “strftime” originates > I described the date\_available field in the table products(from tutorial > “depot”) as type datetime. I changed the table type of date\_available as > “date” when I had the error when running the program “list .rhtml” in my > browser Firefox. > JIm What error do you have that you are trying to correct? datetime is the type stored in the database only, in your product object the attribute date\_available will be of class Time… strftime is a method of Time. You may get an error when date\_available is not set in a record you wish to display/list, it will complain that no such method nil.strftime exists. Try the line: \<%= product.date\_available.strftime("%y-%m-%d") unless product.date\_available.nil? %\> Or logic to that effect, alternatives can be found by searching the list archive. Cheers, Mark ---
**Author:** ![SIX-S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/977dab/32.png) [@SIX-S](https://www.ruby-forum.com/u/SIX-S)\ **Post date:** [May 6, 2006, 11:38pm UTC](https://www.ruby-forum.com/t/checking-date/94106/5 "2006-05-06T23:38:52Z")
I have a problem like the one described. My database has a a table paintings with a DATETIME field called creation\_date. In list.rhtml I code: painting.creation\_date.strftime("%y-%m-%d") Rails complains: You have a nil object when you didn’t expect it! The error occured while evaluating nil.strftime I’m sure the expression painting.creation\_date results in a variable of class Time, as the expression painting.creation\_date.class returns Time. So why does Rails think that painting.creation\_date is a nil object? ---
**Author:** ![SIX-S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/977dab/32.png) [@SIX-S](https://www.ruby-forum.com/u/SIX-S)\ **Post date:** [May 7, 2006, 12:18am UTC](https://www.ruby-forum.com/t/checking-date/94106/6 "2006-05-07T00:18:37Z")
He, I found out why Rails complains about nil.strftime: I have rows in my database with no value for the field creation\_date. So, as a matter of fact, Rails doesn’t complain about errors in the code. While running the code Rails is checking (or reading) the database and finds nil values for the creation\_date fields of some rows. That’s what is reported as nil.strftime ---
**Author:** ![SIX-S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/977dab/32.png) [@SIX-S](https://www.ruby-forum.com/u/SIX-S)\ **Post date:** [May 7, 2006, 7:56am UTC](https://www.ruby-forum.com/t/checking-date/94106/7 "2006-05-07T07:56:21Z")
Anonymous wrote: > He, I found out why Rails complains about nil.strftime: > I have rows in my database with no value for the field creation\_date. > So, as a matter of fact, Rails doesn’t complain about errors in the > code. While running the code Rails is checking (or reading) the database > and finds nil values for the creation\_date fields of some rows. That’s > what is reported as nil.strftime For the record, Rails has a nifty little feature where if you create a table with a field named “created\_on” it will automatically populate new rows with the current date. ---
**Author:** ![SIX-S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/977dab/32.png) [@SIX-S](https://www.ruby-forum.com/u/SIX-S)\ **Post date:** [May 7, 2006, 11:04pm UTC](https://www.ruby-forum.com/t/checking-date/94106/8 "2006-05-07T23:04:20Z")
Thanks for the reply Adam. I knew about the feature and it is indeed useful. My creation\_date field though, wasn’t about the creation of the row but about the creation of the product itself. But I am certainly going to use created\_on.