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How can I rename a database column in a Ruby on Rails migration?
...ing
end
end
For Rails 3.1 use:
While, the up and down methods still apply, Rails 3.1 receives a change method that "knows how to migrate your database and reverse it when the migration is rolled back without the need to write a separate down method".
See "Active Record Migrations" for more i...
Create JSON-object the correct way
...
maybe this will be helpful for someone - jsonwrapper boutell.com/scripts/jsonwrapper.html json_(en|de)code for earlier versions of PHP
– robertbasic
Jul 19 '10 at 17:50
...
Mechanisms for tracking DB schema changes [closed]
...ations typically have two methods: an "up" method in which the changes are applied and a "down" method in which the changes are undone. A single command brings the database up to date, and can also be used to bring the database to a specific version of the schema. In Rails, migrations are kept in th...
Maven dependency for Servlet 3.0 API?
...e provided in Tomcat. Only JSTL (if used) needs to be bundled with the web app.
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.0.1</version>
<scope>provided</scope>
</depend...
Can not connect to local PostgreSQL
...he socket file and its directories /var and /var/pgsql_socket. Your Rails app (OSX user) must have execute (x) permissions on these directories (preferably grant everyone permissions) and the socket should have full permissions (wrx). You can use ls -lAd <file> to check these, and if any of t...
List of encodings that Node.js supports
...onv/-/iconv-2.0.4.tgz
> iconv@2.0.4 install /Users/markboyd/git/portal/app/node_modules/iconv
> node-gyp rebuild
gyp http GET http://nodejs.org/dist/v0.10.1/node-v0.10.1.tar.gz
gyp http 200 http://nodejs.org/dist/v0.10.1/node-v0.10.1.tar.gz
xcode-select: Error: No Xcode is selected. Use xcod...
Android Studio needs JDK 7 for Android-L mac
I was trying to look how my app looks in material design and I would like to use the new cards lib.
My Problem is, that it's giving me this error within my gradle file and I need to fix that.
...
SQLite add Primary Key
... Please bestow your wisdom upon us. Clearly you want people to know you disapprove of the answer or something that one of the commenters said, however your comment contains no information at all, beside an apparent intent to convey superiority and snark.
– Nathan Ridley
...
In C/C++ what's the simplest way to reverse the order of bits in a byte?
...a script which outputs the table of the first 256 bytes and their reverse mapping. Yes, you're back to writing the reverse function, but now in your favourite scripting language, and it can be as nasty as you want -- you're going to throw it away as soon as it's done and you ran it once. Have the sc...
Rails: How can I set default values in ActiveRecord?
...please use Base.after_initialize :method instead. (called from /Users/me/myapp/app/models/my_model:15)
Therefore I'd say write an after_initialize callback, which lets you default attributes in addition to letting you set defaults on associations like so:
class Person < ActiveRecord::Base
...