title: PANDAS read_sql faults when running NOSE test - Could not parse rfc1738 URL from string
body: <p>Have you seen this pandas sqlite error? <code>ArgumentError("Could not parse rfc1738 URL from string '/')</code>? It only happens in a NOSE test.</p>
  
  <p>From the other questions on SO, the err seems to be related to sqlite. But I can't tell how since there are no others using a simple sqlite3 db like I am.</p>
  
  <p>In my unit test, I call a class method that reads from an sqlite3 DB via <code>pandas read_sql</code>. It works perfectly in any python session as well as Jupyter notebook. But for some reason when I run the code through a nosetest, nose tells me there's an Argument Error. And I cannot reproduce it.</p>
  
  <p>I've confirmed the DB is working properly. As I mentioned, the pd.read_sql works perfectly in any other setting.</p>
  
  <p>In the method definition, I am doing the following read, </p>
  
  <pre><code># get data
  div_query = 'SELECT * FROM Dividends WHERE Symbol == "{stock}"'.format(stock = symbol)
  div_history = pd.read_sql(div_query, con=dbcnx)
  </code></pre>
  
  <p>And in the NOSE test, </p>
  
  <pre><code>def test_shiftBeforeDividend():
      # here is where the err occurs
      result = filters.shiftBeforeDividend('DUK') 
      # result now equals ArgumentError("Could not parse rfc1738 URL from string '/'")
  
  def setup():
      try:    
          db = 'mydb.db'
          test_class.connectToDB(db)
          return test_class
  
      except Exception as e:
          return e
  
  def teardown():
      try:
          filters.closeDBConnection(self.dbcnx[0])
  
      except Exception as e:
          return e
  
  # startup
  filters = setup()
  </code></pre>
  
  <p>Any ideas on how to eliminate the issue?</p>