Connecting to MySQL DB in Ruby Rspec
1)...                                       #skipped irrelevant info
   Failure/Error: graph.read_db('example1')
   Not connected to any DB.                 #error msg
   #./prim.rb:135:in 'read_db'
   #./prim_spec.rb:171:in 'block (2 levels) in <top (required)>'

describe PGraph, "online" do
    before (:all) do
        ActiveRecord::Base.establish_connection(
        :adapter => "mysql2",
        :host => "localhost",
        :username => "root",
        :password => "xxxxx",
        :database => "rubytasks" )
        #the exact same statement works perfectly when running the program itself, but fails in RSpec
    end
    before (:each) do
        @graph = PGraph.new
    end

    it "should correctly retrieve data from database" do
        @graph.read_db('example1')   #line 171
        #business part goes here
    end
end

class PGraph
    def read_db(graphID)
        #the error which is raised (line 135):
        raise "Not connected to any DB." unless ActiveRecord::Base.connected?
        #reading goes here
    end
end