This method returns a list of tuples containing warnings generated by previously executed statement. Use the connection's get_warnings property to set whether warnings are to be fetched.

The following example shows a SELECT statement which generated a warning:

>>> cnx.get_warnings = True
>>> cursor.execute('SELECT "a"+1')
>>> cursor.fetchall()
[(1.0,)]
>>> cursor.fetchwarnings()
[(u'Warning', 1292, u"Truncated incorrect DOUBLE value: 'a'")]

It is also possible to raise errors when warnings are found. See the MySQLConnection raise_on_warnings property.