text: # mysql/pyodbc.py
  # Copyright (C) 2005-2017 the SQLAlchemy authors and contributors
  # <see AUTHORS file>
  #
  # This module is part of SQLAlchemy and is released under
  # the MIT License: http://www.opensource.org/licenses/mit-license.php
  
  """
  
  
  .. dialect:: mysql+pyodbc
      :name: PyODBC
      :dbapi: pyodbc
      :connectstring: mysql+pyodbc://<username>:<password>@<dsnname>
      :url: http://pypi.python.org/pypi/pyodbc/
  
      .. note:: The PyODBC for MySQL dialect is not well supported, and
         is subject to unresolved character encoding issues
         which exist within the current ODBC drivers available.
         (see http://code.google.com/p/pyodbc/issues/detail?id=25).
         Other dialects for MySQL are recommended.
  
  """
  
  from .base import MySQLDialect, MySQLExecutionContext
  from ...connectors.pyodbc import PyODBCConnector
  from ... import util
  import re
  
  
  class MySQLExecutionContext_pyodbc(MySQLExecutionContext):
  
      def get_lastrowid(self):
          cursor = self.create_cursor()
          cursor.execute("SELECT LAST_INSERT_ID()")
          lastrowid = cursor.fetchone()[0]
          cursor.close()
          return lastrowid
  
  
  class MySQLDialect_pyodbc(PyODBCConnector, MySQLDialect):
      supports_unicode_statements = False
      execution_ctx_cls = MySQLExecutionContext_pyodbc
  
      pyodbc_driver_name = "MySQL"
  
      def __init__(self, **kw):
          # deal with http://code.google.com/p/pyodbc/issues/detail?id=25
          kw.setdefault('convert_unicode', True)
          super(MySQLDialect_pyodbc, self).__init__(**kw)
  
      def _detect_charset(self, connection):
          """Sniff out the character set in use for connection results."""
  
          # Prefer 'character_set_results' for the current connection over the
          # value in the driver.  SET NAMES or individual variable SETs will
          # change the charset without updating the driver's view of the world.
          #
          # If it's decided that issuing that sort of SQL leaves you SOL, then
          # this can prefer the driver value.
          rs = connection.execute("SHOW VARIABLES LIKE 'character_set%%'")
          opts = dict([(row[0], row[1]) for row in self._compat_fetchall(rs)])
          for key in ('character_set_connection', 'character_set'):
              if opts.get(key, None):
                  return opts[key]
  
          util.warn("Could not detect the connection character set.  "
                    "Assuming latin1.")
          return 'latin1'
  
      def _extract_error_code(self, exception):
          m = re.compile(r"\((\d+)\)").search(str(exception.args))
          c = m.group(1)
          if c:
              return int(c)
          else:
              return None
  
  dialect = MySQLDialect_pyodbc
  