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POAt what point does ActiveRecord actually connect to the database?
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  1. POAt what point does ActiveRecord actually connect to the database?
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    copied!<p>I have a ruby script that is using ActiveRecord (2.3.12) to access a MySQL database. The flow goes something like, "read database values from a config file", "connect to database", "Create table <code>A</code> if it doesn't exist", "download and parse a file", "save parsed records to <code>A</code>".</p> <p>The code looks like the following:</p> <pre><code>ActiveRecord::Base.establish_connection( :adapter =&gt; 'mysql', :database =&gt; database_name, :username =&gt; username, :password =&gt; password, :host =&gt; "localhost", :port =&gt; 3306 ) ... ActiveRecord::Schema.define do create_table a, :force =&gt; true do |t| t.string :last_name, :limit =&gt; 60, :default =&gt; "", :null =&gt; false t.string :first_name, :limit =&gt; 30, :default =&gt; "", :null =&gt; false t.string :middle_initial, :limit =&gt; 2, :default =&gt; "" t.string :dob, :limit =&gt; 12, :default =&gt; "", :null =&gt; false end end unless A.table_exists? </code></pre> <p>However, if I put incorrect DB credentials, or a non-existent database name into the <code>establish_connection</code> method, the script doesn't seem to give any errors or throw any exceptions until I actually try to perform some operation on the database (i.e., create table <code>A</code>). I tried a <code>begin-rescue-end</code> around <code>establish_connection</code>, but it never went into the <code>rescue</code> block.</p> <p>Why does <code>establish_connection</code> seem to not really...well...establish the connection? And for the life of me, I can't figure out what it is even supposed to return. The docs <a href="http://api.rubyonrails.org/v2.3.8/classes/ActiveRecord/Base.html#M001778" rel="nofollow">HERE</a> sure don't seem to be any help.</p> <p>Or am I doing something wrong? Please help!</p>
 

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