Exception occuring when updating database schema in symfony
<p>I am pretty new to Symfony and Doctrine and as such have been playing around with a branch of some code which I will need to be working on commercially in the near future.</p>

<p>To cut a long story short I am at the stage now where I have amended an existing entity in order to add a new parameter. I have updated the ORM annotation to represent this, as I understand it if I run the following:</p>

<pre><code>php app/console doctrine:migrations:diff
</code></pre>

<p>This should automatically update the database table to add a new column to accommodate my new property. However when I run it I get the following error:</p>

<pre><code> [Doctrine\DBAL\Exception\ConnectionException]                                                                                                      
  An exception occured in driver: SQLSTATE[HY000] [2002] php_network_getaddresses: getaddrinfo failed: nodename nor servname provided, or not known  
</code></pre>

<p>Its probably worth noting that the project is already communicating with the database successfully when you interact with it via forms in the browser so i'm rather confused why this error is appearing?</p>

<p>I am also running the database on a docker container, which I assume is probably contributing to this error.</p>

<p>Any ideas?</p>