The difference relies in how the symbol is converted into its respective column type in query language. with MySQL :string is mapped to VARCHAR(255) https://edgeguides.rubyonrails.org/active_record_migrations.html :string | VARCHAR | :limit => 1 to 255 (default = 255) :text | TINYTEXT, TEXT, MEDIUMTEXT, or LONGTEXT2 | :limit => 1 to 4294967296 (default = 65536) Reference: Working … Read more
First, if you have already run the migrations generated by the scaffold command, you have to perform a rollback first. rake db:rollback You can create scaffolding using: rails generate scaffold MyFoo (or similar), and you can destroy/undo it using rails destroy scaffold MyFoo That will delete all the files created by generate, but not any … Read more
Don’t render 404 yourself, there’s no reason to; Rails has this functionality built in already. If you want to show a 404 page, create a render_404 method (or not_found as I called it) in ApplicationController like this: def not_found raise ActionController::RoutingError.new(‘Not Found’) end Rails also handles AbstractController::ActionNotFound, and ActiveRecord::RecordNotFound the same way. This does two … Read more
You won’t always be able to simply generate the migration to already have the code you want. You can create an empty migration and then populate it with the code you need. You can find information about how to accomplish different tasks in a migration here: http://api.rubyonrails.org/classes/ActiveRecord/Migration.html More specifically, you can see how to drop … Read more
After some search for a solution it turns out the -dev package is needed, not just ruby1.8. So if you have ruby1.9.1 doing sudo apt-get install ruby1.9.1-dev or to install generic ruby version, use (as per @lamplightdev comment): sudo apt-get install ruby-dev should fix it. Try locate mkmf to see if the file is actually … Read more
The word “deployment” can have two meanings depending on the context. You are also confusing the roles of Apache/Nginx with the roles of other components. Historic note: This article was originally written on November 6, 2010, when the Ruby app server ecosystem was limited. I’ve updated this article on March 15 2013 with all the … Read more
Yes, ensure ensures that the code is always evaluated. That’s why it’s called ensure. So, it is equivalent to Java’s and C#’s finally. The general flow of begin/rescue/else/ensure/end looks like this: begin # something which might raise an exception rescue SomeExceptionClass => some_variable # code that deals with some exception rescue SomeOtherException => some_other_variable # … Read more
Had a similar problem; a pid file was blocking postgres from starting up. To fix it: $ rm /usr/local/var/postgres/postmaster.pid $ brew services restart postgresql and then all is well. UPDATE: For Apple M1 (Big Sur) users, do this instead: $ rm /opt/homebrew/var/postgres/postmaster.pid $ brew services restart postgresql
I know two ways to do this: This will reset your database and reload your current schema with all: rake db:reset db:migrate This will destroy your db and then create it and then migrate your current schema: rake db:drop db:create db:migrate All data will be lost in both scenarios.
So I found it out by myself. It is actually a pretty simple but powerful concept. It has to do with code reuse as in the example below. Basically, the idea is to extract common and / or context specific chunks of code in order to clean up the models and avoid them getting too … Read more