# Delete rows not updated **URL:** \ **Category:** Rails\ **Created:** [January 5, 2009, 9:16pm UTC](https://www.ruby-forum.com/t/delete-rows-not-updated/156960 "2009-01-05T21:16:18Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![casper\_the\_ghost](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/58956e/32.png) [@casper\_the\_ghost](https://www.ruby-forum.com/u/casper_the_ghost)\ **Post date:** [January 5, 2009, 9:16pm UTC](https://www.ruby-forum.com/t/delete-rows-not-updated/156960/1 "2009-01-05T21:16:18Z")
Is there an easy way to delete all rows not updated when done updating a db? ---
**Author:** ![casper\_the\_ghost](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/58956e/32.png) [@casper\_the\_ghost](https://www.ruby-forum.com/u/casper_the_ghost)\ **Post date:** [January 5, 2009, 9:29pm UTC](https://www.ruby-forum.com/t/delete-rows-not-updated/156960/2 "2009-01-05T21:29:15Z")
On Jan 5, 2:15 pm, Me [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Is there an easy way to delete all rows not updated when done updating > a db? What in the world do you mean? Hard to answer a question without any details or context to what you’re doing. 🙂 Jeff [purpleworkshops.com](http://purpleworkshops.com) ---
**Author:** ![casper\_the\_ghost](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/58956e/32.png) [@casper\_the\_ghost](https://www.ruby-forum.com/u/casper_the_ghost)\ **Post date:** [January 5, 2009, 9:32pm UTC](https://www.ruby-forum.com/t/delete-rows-not-updated/156960/3 "2009-01-05T21:32:46Z")
I have a table of data that I update with a file. I would like to delete all data that does not get updated. ---
**Author:** ![casper\_the\_ghost](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/58956e/32.png) [@casper\_the\_ghost](https://www.ruby-forum.com/u/casper_the_ghost)\ **Post date:** [January 5, 2009, 10:50pm UTC](https://www.ruby-forum.com/t/delete-rows-not-updated/156960/4 "2009-01-05T22:50:58Z")
How are you checking to see if the row was updated or not? By the updated\_at timestamp, or something else? I’m not sure if you’re asking for help coming up with a way to determine whether or not a row should be deleted, or just how to delete it. The how to delete is simple enough, I guess. Just loop through the records and call destroy on the object if it doesn’t meet your criteria with something like this: @records.each { |record| record.destroy if/unless # insert your logic here } – Josh [http://iammrjoshua.com](http://iammrjoshua.com) Me wrote: > I have a table of data that I update with a file. I would like to > delete all data that does not get updated. ---
**Author:** ![casper\_the\_ghost](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/58956e/32.png) [@casper\_the\_ghost](https://www.ruby-forum.com/u/casper_the_ghost)\ **Post date:** [January 5, 2009, 10:55pm UTC](https://www.ruby-forum.com/t/delete-rows-not-updated/156960/5 "2009-01-05T22:55:31Z")
Well that is the problem i need to find out which record have not been updated so i can delete them. How do i do that? On Jan 5, 3:50 pm, Joshua A. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) ---
**Author:** ![casper\_the\_ghost](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/58956e/32.png) [@casper\_the\_ghost](https://www.ruby-forum.com/u/casper_the_ghost)\ **Post date:** [January 6, 2009, 12:23am UTC](https://www.ruby-forum.com/t/delete-rows-not-updated/156960/6 "2009-01-06T00:23:59Z")
On Mon, Jan 5, 2009 at 12:32 PM, Me [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > I have a table of data that I update with a file. I would like to > delete all data that does not get updated. We’ve done stuff like this before. One pattern that we used was: 1. At the beginning of the import process, we’d set a unique value (like a timestamp/date) 2. We’d update an attribute in the table for all records with that value: example: last\_import = 20081231 1. then run your import/update process… 2. then delete any records that last\_import != 20081231 voila! Robby – Robby R. Chief Evangelist, Partner PLANET ARGON, LLC design // development // hosting w/Ruby on Rails > **[Planet Argon](https://www.planetargon.com/)** > > Planet Argon is a Ruby on Rails development agency specializing in maintenance and support for existing Rails apps. Based in Portland, OR, Planet Argon has been a member of the Rails community since 2004. [http://www.robbyonrails.com/](http://www.robbyonrails.com/) aim: planetargon +1 503 445 2457 +1 877 55 ARGON [toll free] +1 815 642 4068 [fax]