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authorfarcepest <farcepest@gmail.com>2012-10-08 11:32:11 -0400
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+====================
+MySQLdb User's Guide
+====================
+
+.. contents::
+..
+
+Introduction
+------------
+
+MySQLdb is an thread-compatible interface to the popular MySQL
+database server that provides the Python database API.
+
+Installation
+------------
+
+The ``README`` file has complete installation instructions.
+
+
+_mysql
+------
+
+If you want to write applications which are portable across databases,
+use MySQLdb_, and avoid using this module directly. ``_mysql``
+provides an interface which mostly implements the MySQL C API. For
+more information, see the `MySQL documentation`_. The documentation
+for this module is intentionally weak because you probably should use
+the higher-level MySQLdb module. If you really need it, use the
+standard MySQL docs and transliterate as necessary.
+
+.. _`MySQL documentation`: http://dev.mysql.com/doc/
+
+
+MySQL C API translation
+.......................
+
+The MySQL C API has been wrapped in an object-oriented way. The only
+MySQL data structures which are implemented are the ``MYSQL``
+(database connection handle) and ``MYSQL_RES`` (result handle)
+types. In general, any function which takes ``MYSQL *mysql`` as an
+argument is now a method of the connection object, and any function
+which takes ``MYSQL_RES *result`` as an argument is a method of the
+result object. Functions requiring none of the MySQL data structures
+are implemented as functions in the module. Functions requiring one of
+the other MySQL data structures are generally not implemented.
+Deprecated functions are not implemented. In all cases, the ``mysql_``
+prefix is dropped from the name. Most of the ``conn`` methods listed
+are also available as MySQLdb Connection object methods. Their use is
+non-portable.
+
+MySQL C API function mapping
+............................
+
+=================================== ==================================
+ C API ``_mysql``
+=================================== ==================================
+ ``mysql_affected_rows()`` ``conn.affected_rows()``
+ ``mysql_autocommit()`` ``conn.autocommit()``
+ ``mysql_character_set_name()`` ``conn.character_set_name()``
+ ``mysql_close()`` ``conn.close()``
+ ``mysql_commit()`` ``conn.commit()``
+ ``mysql_connect()`` ``_mysql.connect()``
+ ``mysql_data_seek()`` ``result.data_seek()``
+ ``mysql_debug()`` ``_mysql.debug()``
+ ``mysql_dump_debug_info`` ``conn.dump_debug_info()``
+ ``mysql_escape_string()`` ``_mysql.escape_string()``
+ ``mysql_fetch_row()`` ``result.fetch_row()``
+ ``mysql_get_character_set_info()`` ``conn.get_character_set_info()``
+ ``mysql_get_client_info()`` ``_mysql.get_client_info()``
+ ``mysql_get_host_info()`` ``conn.get_host_info()``
+ ``mysql_get_proto_info()`` ``conn.get_proto_info()``
+ ``mysql_get_server_info()`` ``conn.get_server_info()``
+ ``mysql_info()`` ``conn.info()``
+ ``mysql_insert_id()`` ``conn.insert_id()``
+ ``mysql_num_fields()`` ``result.num_fields()``
+ ``mysql_num_rows()`` ``result.num_rows()``
+ ``mysql_options()`` various options to ``_mysql.connect()``
+ ``mysql_ping()`` ``conn.ping()``
+ ``mysql_query()`` ``conn.query()``
+ ``mysql_real_connect()`` ``_mysql.connect()``
+ ``mysql_real_query()`` ``conn.query()``
+ ``mysql_real_escape_string()`` ``conn.escape_string()``
+ ``mysql_rollback()`` ``conn.rollback()``
+ ``mysql_row_seek()`` ``result.row_seek()``
+ ``mysql_row_tell()`` ``result.row_tell()``
+ ``mysql_select_db()`` ``conn.select_db()``
+ ``mysql_set_character_set()`` ``conn.set_character_set()``
+ ``mysql_ssl_set()`` ``ssl`` option to ``_mysql.connect()``
+ ``mysql_stat()`` ``conn.stat()``
+ ``mysql_store_result()`` ``conn.store_result()``
+ ``mysql_thread_id()`` ``conn.thread_id()``
+ ``mysql_thread_safe_client()`` ``conn.thread_safe_client()``
+ ``mysql_use_result()`` ``conn.use_result()``
+ ``mysql_warning_count()`` ``conn.warning_count()``
+ ``CLIENT_*`` ``MySQLdb.constants.CLIENT.*``
+ ``CR_*`` ``MySQLdb.constants.CR.*``
+ ``ER_*`` ``MySQLdb.constants.ER.*``
+ ``FIELD_TYPE_*`` ``MySQLdb.constants.FIELD_TYPE.*``
+ ``FLAG_*`` ``MySQLdb.constants.FLAG.*``
+=================================== ==================================
+
+
+Some _mysql examples
+....................
+
+Okay, so you want to use ``_mysql`` anyway. Here are some examples.
+
+The simplest possible database connection is::
+
+ import _mysql
+ db=_mysql.connect()
+
+This creates a connection to the MySQL server running on the local
+machine using the standard UNIX socket (or named pipe on Windows),
+your login name (from the USER environment variable), no password, and
+does not ``USE`` a database. Chances are you need to supply more
+information.::
+
+ db=_mysql.connect("localhost","joebob","moonpie","thangs")
+
+This creates a connection to the MySQL server running on the local
+machine via a UNIX socket (or named pipe), the user name "joebob", the
+password "moonpie", and selects the initial database "thangs".
+
+We haven't even begun to touch upon all the parameters ``connect()``
+can take. For this reason, I prefer to use keyword parameters::
+
+ db=_mysql.connect(host="localhost",user="joebob",
+ passwd="moonpie",db="thangs")
+
+This does exactly what the last example did, but is arguably easier to
+read. But since the default host is "localhost", and if your login
+name really was "joebob", you could shorten it to this::
+
+ db=_mysql.connect(passwd="moonpie",db="thangs")
+
+UNIX sockets and named pipes don't work over a network, so if you
+specify a host other than localhost, TCP will be used, and you can
+specify an odd port if you need to (the default port is 3306)::
+
+ db=_mysql.connect(host="outhouse",port=3307,passwd="moonpie",db="thangs")
+
+If you really had to, you could connect to the local host with TCP by
+specifying the full host name, or 127.0.0.1.
+
+Generally speaking, putting passwords in your code is not such a good
+idea::
+
+ db=_mysql.connect(host="outhouse",db="thangs",read_default_file="~/.my.cnf")
+
+This does what the previous example does, but gets the username and
+password and other parameters from ~/.my.cnf (UNIX-like systems). Read
+about `option files`_ for more details.
+
+.. _`option files`: http://dev.mysql.com/doc/mysql/en/Option_files.html
+
+So now you have an open connection as ``db`` and want to do a
+query. Well, there are no cursors in MySQL, and no parameter
+substitution, so you have to pass a complete query string to
+``db.query()``::
+
+ db.query("""SELECT spam, eggs, sausage FROM breakfast
+ WHERE price < 5""")
+
+There's no return value from this, but exceptions can be raised. The
+exceptions are defined in a separate module, ``_mysql_exceptions``,
+but ``_mysql`` exports them. Read DB API specification PEP-249_ to
+find out what they are, or you can use the catch-all ``MySQLError``.
+
+.. _PEP-249: http://www.python.org/peps/pep-0249.html
+
+At this point your query has been executed and you need to get the
+results. You have two options::
+
+ r=db.store_result()
+ # ...or...
+ r=db.use_result()
+
+Both methods return a result object. What's the difference?
+``store_result()`` returns the entire result set to the client
+immediately. If your result set is really large, this could be a
+problem. One way around this is to add a ``LIMIT`` clause to your
+query, to limit the number of rows returned. The other is to use
+``use_result()``, which keeps the result set in the server and sends
+it row-by-row when you fetch. This does, however, tie up server
+resources, and it ties up the connection: You cannot do any more
+queries until you have fetched **all** the rows. Generally I
+recommend using ``store_result()`` unless your result set is really
+huge and you can't use ``LIMIT`` for some reason.
+
+Now, for actually getting real results::
+
+ >>> r.fetch_row()
+ (('3','2','0'),)
+
+This might look a little odd. The first thing you should know is,
+``fetch_row()`` takes some additional parameters. The first one is,
+how many rows (``maxrows``) should be returned. By default, it returns
+one row. It may return fewer rows than you asked for, but never
+more. If you set ``maxrows=0``, it returns all rows of the result
+set. If you ever get an empty tuple back, you ran out of rows.
+
+The second parameter (``how``) tells it how the row should be
+represented. By default, it is zero which means, return as a tuple.
+``how=1`` means, return it as a dictionary, where the keys are the
+column names, or ``table.column`` if there are two columns with the
+same name (say, from a join). ``how=2`` means the same as ``how=1``
+except that the keys are *always* ``table.column``; this is for
+compatibility with the old ``Mysqldb`` module.
+
+OK, so why did we get a 1-tuple with a tuple inside? Because we
+implicitly asked for one row, since we didn't specify ``maxrows``.
+
+The other oddity is: Assuming these are numeric columns, why are they
+returned as strings? Because MySQL returns all data as strings and
+expects you to convert it yourself. This would be a real pain in the
+ass, but in fact, ``_mysql`` can do this for you. (And ``MySQLdb``
+does do this for you.) To have automatic type conversion done, you
+need to create a type converter dictionary, and pass this to
+``connect()`` as the ``conv`` keyword parameter.
+
+The keys of ``conv`` should be MySQL column types, which in the
+C API are ``FIELD_TYPE_*``. You can get these values like this::
+
+ from MySQLdb.constants import FIELD_TYPE
+
+By default, any column type that can't be found in ``conv`` is
+returned as a string, which works for a lot of stuff. For our
+purposes, we probably want this::
+
+ my_conv = { FIELD_TYPE.LONG: int }
+
+This means, if it's a ``FIELD_TYPE_LONG``, call the builtin ``int()``
+function on it. Note that ``FIELD_TYPE_LONG`` is an ``INTEGER``
+column, which corresponds to a C ``long``, which is also the type used
+for a normal Python integer. But beware: If it's really an ``UNSIGNED
+INTEGER`` column, this could cause overflows. For this reason,
+``MySQLdb`` actually uses ``long()`` to do the conversion. But we'll
+ignore this potential problem for now.
+
+Then if you use ``db=_mysql.connect(conv=my_conv...)``, the
+results will come back ``((3, 2, 0),)``, which is what you would
+expect.
+
+MySQLdb
+-------
+
+MySQLdb is a thin Python wrapper around ``_mysql`` which makes it
+compatible with the Python DB API interface (version 2). In reality,
+a fair amount of the code which implements the API is in ``_mysql``
+for the sake of efficiency.
+
+The DB API specification PEP-249_ should be your primary guide for
+using this module. Only deviations from the spec and other
+database-dependent things will be documented here.
+
+Functions and attributes
+........................
+
+Only a few top-level functions and attributes are defined within
+MySQLdb.
+
+connect(parameters...)
+ Constructor for creating a connection to the
+ database. Returns a Connection Object. Parameters are the
+ same as for the MySQL C API. In addition, there are a few
+ additional keywords that correspond to what you would pass
+ ``mysql_options()`` before connecting. Note that some
+ parameters must be specified as keyword arguments! The
+ default value for each parameter is NULL or zero, as
+ appropriate. Consult the MySQL documentation for more
+ details. The important parameters are:
+
+ host
+ name of host to connect to. Default: use the local host
+ via a UNIX socket (where applicable)
+
+ user
+ user to authenticate as. Default: current effective user.
+
+ passwd
+ password to authenticate with. Default: no password.
+
+ db
+ database to use. Default: no default database.
+
+ port
+ TCP port of MySQL server. Default: standard port (3306).
+
+ unix_socket
+ location of UNIX socket. Default: use default location or
+ TCP for remote hosts.
+
+ conv
+ type conversion dictionary. Default: a copy of
+ ``MySQLdb.converters.conversions``
+
+ compress
+ Enable protocol compression. Default: no compression.
+
+ connect_timeout
+ Abort if connect is not completed within
+ given number of seconds. Default: no timeout (?)
+
+ named_pipe
+ Use a named pipe (Windows). Default: don't.
+
+ init_command
+ Initial command to issue to server upon
+ connection. Default: Nothing.
+
+ read_default_file
+ MySQL configuration file to read; see
+ the MySQL documentation for ``mysql_options()``.
+
+ read_default_group
+ Default group to read; see the MySQL
+ documentation for ``mysql_options()``.
+
+ cursorclass
+ cursor class that ``cursor()`` uses, unless
+ overridden. Default: ``MySQLdb.cursors.Cursor``. *This
+ must be a keyword parameter.*
+
+ use_unicode
+ If True, CHAR and VARCHAR and TEXT columns are returned as
+ Unicode strings, using the configured character set. It is
+ best to set the default encoding in the server
+ configuration, or client configuration (read with
+ read_default_file). If you change the character set after
+ connecting (MySQL-4.1 and later), you'll need to put the
+ correct character set name in connection.charset.
+
+ If False, text-like columns are returned as normal strings,
+ but you can always write Unicode strings.
+
+ *This must be a keyword parameter.*
+
+ charset
+ If present, the connection character set will be changed
+ to this character set, if they are not equal. Support for
+ changing the character set requires MySQL-4.1 and later
+ server; if the server is too old, UnsupportedError will be
+ raised. This option implies use_unicode=True, but you can
+ override this with use_unicode=False, though you probably
+ shouldn't.
+
+ If not present, the default character set is used.
+
+ *This must be a keyword parameter.*
+
+ sql_mode
+ If present, the session SQL mode will be set to the given
+ string. For more information on sql_mode, see the MySQL
+ documentation. Only available for 4.1 and newer servers.
+
+ If not present, the session SQL mode will be unchanged.
+
+ *This must be a keyword parameter.*
+
+ ssl
+ This parameter takes a dictionary or mapping, where the
+ keys are parameter names used by the mysql_ssl_set_ MySQL
+ C API call. If this is set, it initiates an SSL connection
+ to the server; if there is no SSL support in the client,
+ an exception is raised. *This must be a keyword
+ parameter.*
+
+.. _mysql_ssl_set: http://dev.mysql.com/doc/mysql/en/mysql_ssl_set.html
+
+
+apilevel
+ String constant stating the supported DB API level. '2.0'
+
+threadsafety
+ Integer constant stating the level of thread safety the
+ interface supports. This is set to 1, which means: Threads may
+ share the module.
+
+ The MySQL protocol can not handle multiple threads using the
+ same connection at once. Some earlier versions of MySQLdb
+ utilized locking to achieve a threadsafety of 2. While this is
+ not terribly hard to accomplish using the standard Cursor class
+ (which uses ``mysql_store_result()``), it is complicated by
+ SSCursor (which uses ``mysql_use_result()``; with the latter you
+ must ensure all the rows have been read before another query can
+ be executed. It is further complicated by the addition of
+ transactions, since transactions start when a cursor execute a
+ query, but end when ``COMMIT`` or ``ROLLBACK`` is executed by
+ the Connection object. Two threads simply cannot share a
+ connection while a transaction is in progress, in addition to
+ not being able to share it during query execution. This
+ excessively complicated the code to the point where it just
+ isn't worth it.
+
+ The general upshot of this is: Don't share connections between
+ threads. It's really not worth your effort or mine, and in the
+ end, will probably hurt performance, since the MySQL server runs
+ a separate thread for each connection. You can certainly do
+ things like cache connections in a pool, and give those
+ connections to one thread at a time. If you let two threads use
+ a connection simultaneously, the MySQL client library will
+ probably upchuck and die. You have been warned.
+
+ For threaded applications, try using a connection pool.
+ This can be done using the `Pool module`_.
+
+ .. _`Pool module`: http://dustman.net/andy/python/Pool
+
+charset
+ The character set used by the connection. In MySQL-4.1 and newer,
+ it is possible (but not recommended) to change the connection's
+ character set with an SQL statement. If you do this, you'll also
+ need to change this attribute. Otherwise, you'll get encoding
+ errors.
+
+paramstyle
+ String constant stating the type of parameter marker formatting
+ expected by the interface. Set to 'format' = ANSI C printf
+ format codes, e.g. '...WHERE name=%s'. If a mapping object is
+ used for conn.execute(), then the interface actually uses
+ 'pyformat' = Python extended format codes, e.g. '...WHERE
+ name=%(name)s'. However, the API does not presently allow the
+ specification of more than one style in paramstyle.
+
+ Note that any literal percent signs in the query string passed
+ to execute() must be escaped, i.e. %%.
+
+ Parameter placeholders can **only** be used to insert column
+ values. They can **not** be used for other parts of SQL, such as
+ table names, statements, etc.
+
+conv
+ A dictionary or mapping which controls how types are converted
+ from MySQL to Python and vice versa.
+
+ If the key is a MySQL type (from ``FIELD_TYPE.*``), then the value
+ can be either:
+
+ * a callable object which takes a string argument (the MySQL
+ value),' returning a Python value
+
+ * a sequence of 2-tuples, where the first value is a combination
+ of flags from ``MySQLdb.constants.FLAG``, and the second value
+ is a function as above. The sequence is tested until the flags
+ on the field match those of the first value. If both values
+ are None, then the default conversion is done. Presently this
+ is only used to distinquish TEXT and BLOB columns.
+
+ If the key is a Python type or class, then the value is a
+ callable Python object (usually a function) taking two arguments
+ (value to convert, and the conversion dictionary) which converts
+ values of this type to a SQL literal string value.
+
+ This is initialized with reasonable defaults for most
+ types. When creating a Connection object, you can pass your own
+ type converter dictionary as a keyword parameter. Otherwise, it
+ uses a copy of ``MySQLdb.converters.conversions``. Several
+ non-standard types are returned as strings, which is how MySQL
+ returns all columns. For more details, see the built-in module
+ documentation.
+
+
+Connection Objects
+..................
+
+Connection objects are returned by the ``connect()`` function.
+
+commit()
+ If the database and the tables support transactions, this
+ commits the current transaction; otherwise this method
+ successfully does nothing.
+
+rollback()
+ If the database and tables support transactions, this rolls back
+ (cancels) the current transaction; otherwise a
+ ``NotSupportedError`` is raised.
+
+cursor([cursorclass])
+ MySQL does not support cursors; however, cursors are easily
+ emulated. You can supply an alternative cursor class as an
+ optional parameter. If this is not present, it defaults to the
+ value given when creating the connection object, or the standard
+ ``Cursor`` class. Also see the additional supplied cursor
+ classes in the usage section.
+
+There are many more methods defined on the connection object which
+are MySQL-specific. For more information on them, consult the internal
+documentation using ``pydoc``.
+
+
+Cursor Objects
+..............
+
+callproc(procname, args)
+ Calls stored procedure procname with the sequence of arguments
+ in args. Returns the original arguments. Stored procedure
+ support only works with MySQL-5.0 and newer.
+
+ **Compatibility note:** PEP-249_ specifies that if there are
+ OUT or INOUT parameters, the modified values are to be
+ returned. This is not consistently possible with MySQL. Stored
+ procedure arguments must be passed as server variables, and
+ can only be returned with a SELECT statement. Since a stored
+ procedure may return zero or more result sets, it is impossible
+ for MySQLdb to determine if there are result sets to fetch
+ before the modified parmeters are accessible.
+
+ The parameters are stored in the server as @_*procname*_*n*,
+ where *n* is the position of the parameter. I.e., if you
+ cursor.callproc('foo', (a, b, c)), the parameters will be
+ accessible by a SELECT statement as @_foo_0, @_foo_1, and
+ @_foo_2.
+
+ **Compatibility note:** It appears that the mere act of
+ executing the CALL statement produces an empty result set, which
+ appears after any result sets which might be generated by the
+ stored procedure. Thus, you will always need to use nextset() to
+ advance result sets.
+
+close()
+ Closes the cursor. Future operations raise ``ProgrammingError``.
+ If you are using server-side cursors, it is very important to
+ close the cursor when you are done with it and before creating a
+ new one.
+
+info()
+ Returns some information about the last query. Normally
+ you don't need to check this. If there are any MySQL
+ warnings, it will cause a Warning to be issued through
+ the Python warning module. By default, Warning causes a
+ message to appear on the console. However, it is possible
+ to filter these out or cause Warning to be raised as exception.
+ See the MySQL docs for ``mysql_info()``, and the Python warning
+ module. (Non-standard)
+
+setinputsizes()
+ Does nothing, successfully.
+
+setoutputsizes()
+ Does nothing, successfully.
+
+nextset()
+ Advances the cursor to the next result set, discarding the remaining
+ rows in the current result set. If there are no additional result
+ sets, it returns None; otherwise it returns a true value.
+
+ Note that MySQL doesn't support multiple result sets until 4.1.
+
+
+Some examples
+.............
+
+The ``connect()`` method works nearly the same as with `_mysql`_::
+
+ import MySQLdb
+ db=MySQLdb.connect(passwd="moonpie",db="thangs")
+
+To perform a query, you first need a cursor, and then you can execute
+queries on it::
+
+ c=db.cursor()
+ max_price=5
+ c.execute("""SELECT spam, eggs, sausage FROM breakfast
+ WHERE price < %s""", (max_price,))
+
+In this example, ``max_price=5`` Why, then, use ``%s`` in the
+string? Because MySQLdb will convert it to a SQL literal value, which
+is the string '5'. When it's finished, the query will actually say,
+"...WHERE price < 5".
+
+Why the tuple? Because the DB API requires you to pass in any
+parameters as a sequence. Due to the design of the parser, (max_price)
+is interpreted as using algebraic grouping and simply as max_price and
+not a tuple. Adding a comma, i.e. (max_price,) forces it to make a
+tuple.
+
+And now, the results::
+
+ >>> c.fetchone()
+ (3L, 2L, 0L)
+
+Quite unlike the ``_mysql`` example, this returns a single tuple,
+which is the row, and the values are properly converted by default...
+except... What's with the L's?
+
+As mentioned earlier, while MySQL's INTEGER column translates
+perfectly into a Python integer, UNSIGNED INTEGER could overflow, so
+these values are converted to Python long integers instead.
+
+If you wanted more rows, you could use ``c.fetchmany(n)`` or
+``c.fetchall()``. These do exactly what you think they do. On
+``c.fetchmany(n)``, the ``n`` is optional and defaults to
+``c.arraysize``, which is normally 1. Both of these methods return a
+sequence of rows, or an empty sequence if there are no more rows. If
+you use a weird cursor class, the rows themselves might not be tuples.
+
+Note that in contrast to the above, ``c.fetchone()`` returns ``None``
+when there are no more rows to fetch.
+
+The only other method you are very likely to use is when you have to
+do a multi-row insert::
+
+ c.executemany(
+ """INSERT INTO breakfast (name, spam, eggs, sausage, price)
+ VALUES (%s, %s, %s, %s, %s)""",
+ [
+ ("Spam and Sausage Lover's Plate", 5, 1, 8, 7.95 ),
+ ("Not So Much Spam Plate", 3, 2, 0, 3.95 ),
+ ("Don't Wany ANY SPAM! Plate", 0, 4, 3, 5.95 )
+ ] )
+
+Here we are inserting three rows of five values. Notice that there is
+a mix of types (strings, ints, floats) though we still only use
+``%s``. And also note that we only included format strings for one
+row. MySQLdb picks those out and duplicates them for each row.
+
+Using and extending
+-------------------
+
+In general, it is probably wise to not directly interact with the DB
+API except for small applicatons. Databases, even SQL databases, vary
+widely in capabilities and may have non-standard features. The DB API
+does a good job of providing a reasonably portable interface but some
+methods are non-portable. Specifically, the parameters accepted by
+``connect()`` are completely implementation-dependent.
+
+If you believe your application may need to run on several different
+databases, the author recommends the following approach, based on
+personal experience: Write a simplified API for your application which
+implements the specific queries and operations your application needs
+to perform. Implement this API as a base class which should be have
+few database dependencies, and then derive a subclass from this which
+implements the necessary dependencies. In this way, porting your
+application to a new database should be a relatively simple matter of
+creating a new subclass, assuming the new database is reasonably
+standard.
+
+Because MySQLdb's Connection and Cursor objects are written in Python,
+you can easily derive your own subclasses. There are several Cursor
+classes in MySQLdb.cursors:
+
+BaseCursor
+ The base class for Cursor objects. This does not raise Warnings.
+
+CursorStoreResultMixIn
+ Causes the Cursor to use the ``mysql_store_result()`` function to
+ get the query result. The entire result set is stored on the
+ client side.
+
+CursorUseResultMixIn
+ Causes the cursor to use the ``mysql_use_result()`` function to
+ get the query result. The result set is stored on the server side
+ and is transferred row by row using fetch operations.
+
+CursorTupleRowsMixIn
+ Causes the cursor to return rows as a tuple of the column values.
+
+CursorDictRowsMixIn
+
+ Causes the cursor to return rows as a dictionary, where the keys
+ are column names and the values are column values. Note that if
+ the column names are not unique, i.e., you are selecting from two
+ tables that share column names, some of them will be rewritten as
+ ``table.column``. This can be avoided by using the SQL ``AS``
+ keyword. (This is yet-another reason not to use ``*`` in SQL
+ queries, particularly where ``JOIN`` is involved.)
+
+Cursor
+ The default cursor class. This class is composed of
+ ``CursorWarningMixIn``, ``CursorStoreResultMixIn``,
+ ``CursorTupleRowsMixIn,`` and ``BaseCursor``, i.e. it raises
+ ``Warning``, uses ``mysql_store_result()``, and returns rows as
+ tuples.
+
+DictCursor
+ Like ``Cursor`` except it returns rows as dictionaries.
+
+SSCursor
+ A "server-side" cursor. Like ``Cursor`` but uses
+ ``CursorUseResultMixIn``. Use only if you are dealing with
+ potentially large result sets.
+
+SSDictCursor
+ Like ``SSCursor`` except it returns rows as dictionaries.
+
+
+Embedded Server
+---------------
+
+Instead of connecting to a stand-alone server over the network,
+the embedded server support lets you run a full server right in
+your Python code or application server.
+
+If you have built MySQLdb with embedded server support, there
+are two additional functions you will need to make use of:
+
+ server_init(args, groups)
+ Initialize embedded server. If this client is not linked against
+ the embedded server library, this function does nothing.
+
+ args
+ sequence of command-line arguments
+ groups
+ sequence of groups to use in defaults files
+
+ server_end()
+ Shut down embedded server. If not using an embedded server, this
+ does nothing.
+
+See the MySQL documentation for more information on the embedded
+server.
+
+
+
+:Title: MySQLdb: a Python interface for MySQL
+:Author: Andy Dustman
+:Version: $Revision$