title: EF 5 removing quotes on query
body: <p>I'm having a problem with EF5 regarding a string field on database (Oracle) that contains only numbers.</p>
  
  <p>Here's the sample code:</p>
  
  <pre><code>using (Entities ex = new Entities())
  {
  string nrcart = "861858662";
  GLB_PESSOA_OPERADORA pessoa = ex.GLB_PESSOA_OPERADORA.FirstOrDefault(p =&gt; p.NR_CARTEIRINHA == nrcart);
  }
  </code></pre>
  
  <p>My problem is that EF is building the following query to the database:</p>
  
  <pre><code>SELECT "Extent1"."ID_PESSOA_OPERADORA"      AS "ID_PESSOA_OPERADORA",
         "Extent1"."NR_CARTEIRINHA"           AS "NR_CARTEIRINHA"
  FROM   "GLB_PESSOA_OPERADORA" "Extent1"
  WHERE  ("Extent1"."NR_CARTEIRINHA" = 861858662 /* @p__linq__0 */)
    AND (ROWNUM &lt;= (1))
  </code></pre>
  
  <p>Note that the query doesn't surround the parameter with '' on where statement.
  The field in the database, the attribute in the returning class, the mapping on the Model and the nrcart variable are ALL string typed. Why is it removing the quotes?</p>
  
  <p>Without them, the database is not able to use the index and the query is runnig too slow.</p>
  
  <p>Thanks for the help</p>