You could have postgre installed on localhost with password (or without user or password seted after instalation) but if we are developing we really don't need password, so configuring postgre server without password for all your rails project is usefull.
In researching topics for RailsCasts I often read code in Rails and other gems. This is a great exercise to do. Not only will you pick up some coding tips, but it can help you better understand what makes code readable.
A common practice to organize code in gems is to divide it into modules. When this is done extensively I find it becomes very difficult to read. Before I explain further, a quick detour on instance_eval.
You can find instance_eval used in many DSLs: from routes to state machines. Here's an example from Thinking Sphinx.
class Article < ActiveRecord::Base
I'm hunting for the best solution on how to handle keeping large sets of DB records "sorted" in a performant manner.
Most of us have work on projects at some point where we have needed to have ordered lists of objects. Whether it be a to-do list sorted by priority, or a list of documents that a user can sort in whatever order they want.
A traditional approach for this on a Rails project is to use something like the acts_as_list gem, or something similar. These systems typically add some sort of "postion" or "sort order" column to each record, which is then used when querying out the records in a traditional order by position SQL query.
This approach seems to work fine for smaller datasets, but can be hard to manage on large data sets with hundreds (or thousands) of records needing to be sorted. Changing the sort position of even a single object will require updating every single record in the database that is in the same sort group. This requires potentially thousands of wri
| # How Clearance / Hoptoad does it | |
| module Clearance | |
| class << self | |
| attr_accessor :configuration | |
| end | |
| def self.configure | |
| self.configuration ||= Configuration.new | |
| yield(configuration) | |
| end |
| --colour | |
| -I app |
| #!/usr/bin/env ruby | |
| # Put this file in the root of your Rails project, | |
| # then run it to output the SQL needed to change all | |
| # your tables and columns to the same character set | |
| # and collation. | |
| # | |
| # > ruby character_set_and_collation.rb | |
| DATABASE = '' |
| #!/usr/bin/env ruby | |
| CHARACTERS = (('A'..'Z').to_a + ('a'..'z').to_a + (0..9).to_a) | |
| GROUP = 53 | |
| MY_MACHINE_DYNDNS_ADDRESS = "Put your DynDns DNS name here" | |
| MY_SSH_PORT = "Your router's external port that will forward to SSH" # as a Fixnum | |
| def ridiculous_password | |
| (1..20).map do |
| literally always have to look up the meaning of :limit in migrations when it comes to integer values. Here's an overview. Now let's memorise it (oh, this works for MySQL, other databases may work differently): | |
| :limit Numeric Type Column Size Max value | |
| 1 tinyint 1 byte 127 | |
| 2 smallint 2 bytes 32767 | |
| 3 mediumint 3 byte 8388607 | |
| nil, 4, 11 int(11) 4 byte 2147483647 | |
| 5..8 bigint 8 byte 9223372036854775807 | |
| Note: by default MySQL uses signed integers and Rails has no way (that I know of) to change this behaviour. Subsequently, the max. values noted are for signed integers. |
| class MenuEditor::Page::FormWidget < Apotomo::Widget | |
| # Step 1: make sure the current_user variable (or something like it) is available for use | |
| include Devise::Controllers::Helpers | |
| helper_method :current_user | |
| responds_to_event :submit | |
| def display | |
| ... | |
| end |