If you use a form (or form fields) multiple times inside one view, Rails will generate the same id attributes...

Note: For PostgreSQL you should use advisory locks. For MySQL we still recommend the solution in this card.

On 32bit systems, the maximum representable Time is 2038-01-19 03:14:07 in UTC or 2038-01-19...

See our new comprehensive guide for upgrading every Rails 2 version ever.

Note that this sounds good but is not good at all when hooking tasks on cap deploy (see this article...

When you use the send_file method to send a local file to the browser, you can save resources on...

When you try to remove a non-existing index using remove_index, the migration will incorrectly pass without an error...

A check if two date or time ranges A and B overlap needs to cover a lot of cases:

Note: Consider not doing this. Use form models or vanilla methods instead. The :conditions option for Rails associations cannot take...

Sometimes it is useful to define a named scope by implementing a static method with the scope's name on...

Given group size If you would like to split a Ruby array into pairs of two, you can use the...

In case https://www.rubydoc.info/ is to slow or offline, you can also read a gem documentation offline. Start a server...

You cannot use Array#join on an array of strings where some strings are html_safe and others are not...

Update: This trick probably isn't very useful anymore in Ruby 2.x. The Ruby GC has improved a lot...

If you’re testing the behavior of deprecated code in your Ruby project, the warning messages littered throughout your spec...

Git allows you to do a binary search across commits to hunt down the commit that introduced a bug.

If you want to iterate over a Range, but only look at every n-th element, use the step method...

See our new comprehensive guide to upgrading every Rails 2 version ever.

When you need to see the content of a page (i.e. not all the HTML but the relevant text body...

Learning Rails for the first time should be fun, and Rails for Zombies allows you to get your feet wet...

So you added a new callback to your model that (e.g.) caches some data when it is saved. Now you...

How to write to the db 27,000 times in 24 seconds instead of 9 minutes.

When you eagerly load an association list using the .include option, and at the same time have a .where on...

Sometimes, you just need to shoot from the hip…or deploy your local changes without committing them. Put this snippet...