错误是
File "c:\python27\lib\site-packages\MySQLdb\connections.py", line 72, in Connection
db = get_db_connection(db_name)
NameError: name 'get_db_connection' is not defined
所以我认为错误在*这是因为 def init (self, *args, **kwargs): 以冒号结尾，但我不知道连接的语法。
这是我在 connection.py 中的类连接代码
class Connection(_mysql.connection):
"""MySQL Database Connection Object"""
default_cursor = cursors.Cursor
def __init__(self, *args, **kwargs): # *** this is error I think ie the : but what is syntax
def get_db_connection(database_name):
db = MySQLdb.connect('localhost', 'user', 'pswrd', database_name)
cur = db.cursor()
return db, cur
db_name = 'test' # database name
user_name = 'root' # name of a user
db = get_db_connection(db_name)
"""
Create a connection to the database. It is strongly recommended
that you only use keyword parameters. Consult the MySQL C API
documentation for more information.
host
string, host to connect
user
string, user to connect as
passwd
string, password to use
db
string, database to use
port
integer, TCP/IP port to connect to
unix_socket
string, location of unix_socket to use
conv
conversion dictionary, see MySQLdb.converters
connect_timeout
number of seconds to wait before the connection attempt
fails.
compress
if set, compression is enabled
named_pipe
if set, a named pipe is used to connect (Windows only)
init_command
command which is run once the connection is created
read_default_file
file from which default client values are read
read_default_group
configuration group to use from the default file
cursorclass
class object, used to create cursors (keyword only)
use_unicode
If True, text-like columns are returned as unicode objects
using the connection's character set. Otherwise, text-like
columns are returned as strings. columns are returned as
normal strings. Unicode objects will always be encoded to
the connection's character set regardless of this setting.
charset
If supplied, the connection character set will be changed
to this character set (MySQL-4.1 and newer). This implies
use_unicode=True.
sql_mode
If supplied, the session SQL mode will be changed to this
setting (MySQL-4.1 and newer). For more details and legal
values, see the MySQL documentation.
client_flag
integer, flags to use or 0
(see MySQL docs or constants/CLIENTS.py)
ssl
dictionary or mapping, contains SSL connection parameters;
see the MySQL documentation for more details
(mysql_ssl_set()). If this is set, and the client does not
support SSL, NotSupportedError will be raised.
local_infile
integer, non-zero enables LOAD LOCAL INFILE; zero disables
There are a number of undocumented, non-standard methods. See the
documentation for the MySQL C API for some hints on what they do.
"""
from MySQLdb.constants import CLIENT, FIELD_TYPE
from MySQLdb.converters import conversions
from weakref import proxy, WeakValueDictionary
import types
kwargs2 = kwargs.copy()
if 'conv' in kwargs:
conv = kwargs['conv']
else:
conv = conversions
conv2 = {}
for k, v in conv.items():
if isinstance(k, int) and isinstance(v, list):
conv2[k] = v[:]
else:
conv2[k] = v
kwargs2['conv'] = conv2
cursorclass = kwargs2.pop('cursorclass', self.default_cursor)
charset = kwargs2.pop('charset', '')
if charset:
use_unicode = True
else:
use_unicode = False
use_unicode = kwargs2.pop('use_unicode', use_unicode)
sql_mode = kwargs2.pop('sql_mode', '')
client_flag = kwargs.get('client_flag', 0)
client_version = tuple([ numeric_part(n) for n in _mysql.get_client_info().split('.')[:2] ])
if client_version >= (4, 1):
client_flag |= CLIENT.MULTI_STATEMENTS
if client_version >= (5, 0):
client_flag |= CLIENT.MULTI_RESULTS
kwargs2['client_flag'] = client_flag
super(Connection, self).__init__(*args, **kwargs2) #****
self.cursorclass = cursorclass
self.encoders = dict([ (k, v) for k, v in conv.items()
if type(k) is not int ])
self._server_version = tuple([ numeric_part(n) for n in self.get_server_info().split('.')[:2] ])
db = proxy(self)
def _get_string_literal():
def string_literal(obj, dummy=None):
return db.string_literal(obj)
return string_literal
def _get_unicode_literal():
def unicode_literal(u, dummy=None):
return db.literal(u.encode(unicode_literal.charset))
return unicode_literal
def _get_string_decoder():
def string_decoder(s):
return s.decode(string_decoder.charset)
return string_decoder
string_literal = _get_string_literal()
self.unicode_literal = unicode_literal = _get_unicode_literal()
self.string_decoder = string_decoder = _get_string_decoder()
if not charset:
charset = self.character_set_name()
self.set_character_set(charset)
if sql_mode:
self.set_sql_mode(sql_mode)
if use_unicode:
self.converter[FIELD_TYPE.STRING].append((None, string_decoder))
self.converter[FIELD_TYPE.VAR_STRING].append((None, string_decoder))
self.converter[FIELD_TYPE.VARCHAR].append((None, string_decoder))
self.converter[FIELD_TYPE.BLOB].append((None, string_decoder))
self.encoders[types.StringType] = string_literal
self.encoders[types.UnicodeType] = unicode_literal
self._transactional = self.server_capabilities & CLIENT.TRANSACTIONS
if self._transactional:
# PEP-249 requires autocommit to be initially off
self.autocommit(False)
self.messages = []
def cursor(self, cursorclass=None):
"""
Create a cursor on which queries may be performed. The
optional cursorclass parameter is used to create the
Cursor. By default, self.cursorclass=cursors.Cursor is
used.
"""
return (cursorclass or self.cursorclass)(self)
def __enter__(self): return self.cursor()
def __exit__(self, exc, value, tb):
if exc:
self.rollback()
else:
self.commit()
def literal(self, o):
"""
If o is a single object, returns an SQL literal as a string.
If o is a non-string sequence, the items of the sequence are
converted and returned as a sequence.
Non-standard. For internal use; do not use this in your
applications.
"""
return self.escape(o, self.encoders)
def begin(self):
"""Explicitly begin a connection. Non-standard.
DEPRECATED: Will be removed in 1.3.
Use an SQL BEGIN statement instead."""
from warnings import warn
warn("begin() is non-standard and will be removed in 1.3",
DeprecationWarning, 2)
self.query("BEGIN")
if not hasattr(_mysql.connection, 'warning_count'):
def warning_count(self):
"""Return the number of warnings generated from the
last query. This is derived from the info() method."""
from string import atoi
info = self.info()
if info:
return atoi(info.split()[-1])
else:
return 0
def set_character_set(self, charset):
"""Set the connection character set to charset. The character
set can only be changed in MySQL-4.1 and newer. If you try
to change the character set from the current value in an
older version, NotSupportedError will be raised."""
if charset == "utf8mb4":
py_charset = "utf8"
else:
py_charset = charset
if self.character_set_name() != charset:
try:
super(Connection, self).set_character_set(charset)
except AttributeError:
if self._server_version < (4, 1):
raise NotSupportedError("server is too old to set charset")
self.query('SET NAMES %s' % charset)
self.store_result()
self.string_decoder.charset = py_charset
self.unicode_literal.charset = py_charset
def set_sql_mode(self, sql_mode):
"""Set the connection sql_mode. See MySQL documentation for
legal values."""
if self._server_version < (4, 1):
raise NotSupportedError("server is too old to set sql_mode")
self.query("SET SESSION sql_mode='%s'" % sql_mode)
self.store_result()
def show_warnings(self):
"""Return detailed information about warnings as a
sequence of tuples of (Level, Code, Message). This
is only supported in MySQL-4.1 and up. If your server
is an earlier version, an empty sequence is returned."""
if self._server_version < (4,1): return ()
self.query("SHOW WARNINGS")
r = self.store_result()
warnings = r.fetch_row(0)
return warnings
Warning = Warning
Error = Error
InterfaceError = InterfaceError
DatabaseError = DatabaseError
DataError = DataError
OperationalError = OperationalError
IntegrityError = IntegrityError
InternalError = InternalError
ProgrammingError = ProgrammingError
NotSupportedError = NotSupportedError
errorhandler = defaulterrorhandler
这是connection.py中调用该函数的第187行
super(Connection, self).__init__(*args, **kwargs2) #****