When using

uri = URI.parse("http://google.com/")

it is good practice to encode the url with

URI.encode("http://google.com", "[]")

The second argument is optional and could be regex or string. In case of string the symbols are escaped. Check the docs.

https://github.com/zmoazeni/csscss

https://github.com/geuis/helium-css

http://www.cleancss.com/

http://www.makeuseof.com/dir/csssuperscrub-make-css-cleaner/

First check the current version of postgres. I used

apt-show-versions

which is not installed by default on Ubuntu 12.04. You can add it with

sudo apt-get install apt-show-versions

Then run

sudo apt-show-versions | grep postgresql

to see the actual version of the package and if there is newer binary. make sure you execute

sudo apt-get update

to ensure you have an updated packages list.

Upgrading from Postgres 9.2.3 to 9.2.4 took about 10 minutes. The process stops and starts the DB daemon  automatically.

Both gems are using graphviz open source tools for painting diagrams and convert them in PNG or SVG format. There is one more useful open source tool for editing svg formats Inkscape (open source illustrator).

Some snippets
I tried Railroady and it is pretty straightforward to use it. There are two options to add it – either in your Gemfile

group :development do
  gem 'railroady'
end

or install it as separate gem with

gem install railroady

Adding it as a gem has one plus – it adds rake tasks to your project, which is easier to use.

Here are some snippets to generate models and controllers UML diagrams in dot format

railroady -o models.dot -M
railroady -o controllers.dot -C

Converting the dot files to PNG

dot -Tpng models.dot > models.png
neato -Tpng controllers.dot > controllers.png

Or in svg files format

dot -Tsvg models.dot > models.svg
neato -Tscg controllers.dot > controllers.svg

Note the graphviz tools bin directory should be in your environment path. Check the repo for more examples and additional documentation.

Connection configuration
Connecting Matlab to Postgres requires to have JDBC driver, which you can download from here. Select current version or choose one appropriate for you OS from the Supported versions table. Put the jar file somewhere in your drive. I put mine at “C:\Program Files\MATLAB\R2011b\java\jar\postgresql-9.2-1002.jdbc4.jar” (1). Open Matlab command window and type

edit classpath.txt

Add the full path (quoted above) at the end of the file. In my case I added “$matlabroot/java/jar/postgresql-9.2-1002.jdbc4.jar” (2). Then close and start Matlab and verify the driver is loaded with typing in command window

javaclasspath

You should see the added driver path (1) above. Matlab supports connecting with and without SSL. Here are example strings to use in either cases:

JDBC Driver: org.postgresql.Driver
Database URL:jdbc:postgresql://localhost:5432/database_name

JDBC Driver: org.postgresql.Driver
Database URL: jdbc:postgresql:servername:database_name:ssl=true&sslfactory=org.postgresql.ssl.NonValidatingFactory&

Querying connection
Connection string should look like

conn = database(database_name, database_user, user_password, 'Vendor', 'PostGreSQL');

Here is example to query “database_table” and show the data for the first row:

conn = database('database_name', 'database_user', 'user_password', 'org.postgresql.Driver', 'jdbc:postgresql://123.123.123:5432/database_name')
curs = exec(conn, ['SELECT * FROM "database_table";']);
row = fetch(curs, 1);
row.Data

Used arguments are self explaining and should be straightforward to follow.

Installing bcrypt-ruby (3.0.1) 
Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.

    /usr/bin/ruby1.9.1 extconf.rb 
/usr/local/lib/site_ruby/1.9.1/rubygems/core_ext/kernel_require.rb:45:in `require': cannot load such file -- mkmf (LoadError)
    from /usr/local/lib/site_ruby/1.9.1/rubygems/core_ext/kernel_require.rb:45:in `require'
    from extconf.rb:36:in `<main>'

This has a dependency with the dev package, which one can install with

sudo gem install ruby1.9.1-dev

Here is a list of all packages needed when installing rvm.

sudo apt-get install build-essential openssl libreadline6 libreadline6-dev curl git-core zlib1g zlib1g-dev libssl-dev libyaml-dev libsqlite3-0 libsqlite3-dev sqlite3 libxml2-dev libxslt-dev autoconf libc6-dev ncurses-dev automake libtool bison subversion

invalid date format in specification: "2011-08-25 00:00:00.000000000Z"

While one can go through the gems specs and fix the format, one can just install rubygems-update

sudo gem install rubygems-update

Then run that command and should be good to go.

sudo update_rubygems

ERROR: Error installing json.
ERROR: Failed to build gem native extension.

Found solution here. In my case it happen after Windows update and “Scenario B” worked for me.

1. Rename the column to the_geom_1

2. Then add geometry column

SELECT AddGeometryColumn('table_name', 'the_geom', 4326, 'POINT', 2)

3. Move the data from the varchar column to the geometry column

UPDATE table_name SET the_geom = 'SRID=4326;' || ST_AsText(ST_GeomFromEWKT(the_geom_1))

cm_SyncChangeDir