'metadata' is an invalid connection string attribute in ASP.Net MVC using Oracle
<p>In my controller I have a <code>JsonResult</code> function called by a Javascript that's called by a button in <code>View</code>. this will save input from textbox to database table. But in it's first line of code (connecting to Oracle), it's alread having an error:</p>

<pre><code>using (var con = new OracleConnection(ConfigurationManager.ConnectionStrings["DBEntities"].ConnectionString))
</code></pre>

<blockquote>
  <p>An exception of type 'System.ArgumentException' occurred in
  Oracle.DataAccess.dll but was not handled in user code</p>
  
  <p>Additional information: 'metadata' is an invalid connection string
  attribute</p>
</blockquote>

<p>Here's my auto-generated connectionString in web.config:</p>

<pre><code>&lt;add name="DBEntities" connectionString="metadata=res://*/DBModel.csdl|res://*/DBModel.ssdl|res://*/DBModel.msl;provider=Oracle.ManagedDataAccess.Client;provider connection string=&amp;quot;DATA SOURCE=DBDEV;PASSWORD=db;PERSIST SECURITY INFO=True;USER ID=db&amp;quot;" providerName="System.Data.EntityClient" /&gt;
</code></pre>

<p>What seems to be the problem? And how do I fix it?</p>