--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/python-2.6.1/Doc/library/sqlite3.rst Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,860 @@
+:mod:`sqlite3` --- DB-API 2.0 interface for SQLite databases
+============================================================
+
+.. module:: sqlite3
+ :synopsis: A DB-API 2.0 implementation using SQLite 3.x.
+.. sectionauthor:: Gerhard Häring <gh@ghaering.de>
+
+
+.. versionadded:: 2.5
+
+SQLite is a C library that provides a lightweight disk-based database that
+doesn't require a separate server process and allows accessing the database
+using a nonstandard variant of the SQL query language. Some applications can use
+SQLite for internal data storage. It's also possible to prototype an
+application using SQLite and then port the code to a larger database such as
+PostgreSQL or Oracle.
+
+pysqlite was written by Gerhard Häring and provides a SQL interface compliant
+with the DB-API 2.0 specification described by :pep:`249`.
+
+To use the module, you must first create a :class:`Connection` object that
+represents the database. Here the data will be stored in the
+:file:`/tmp/example` file::
+
+ conn = sqlite3.connect('/tmp/example')
+
+You can also supply the special name ``:memory:`` to create a database in RAM.
+
+Once you have a :class:`Connection`, you can create a :class:`Cursor` object
+and call its :meth:`~Cursor.execute` method to perform SQL commands::
+
+ c = conn.cursor()
+
+ # Create table
+ c.execute('''create table stocks
+ (date text, trans text, symbol text,
+ qty real, price real)''')
+
+ # Insert a row of data
+ c.execute("""insert into stocks
+ values ('2006-01-05','BUY','RHAT',100,35.14)""")
+
+ # Save (commit) the changes
+ conn.commit()
+
+ # We can also close the cursor if we are done with it
+ c.close()
+
+Usually your SQL operations will need to use values from Python variables. You
+shouldn't assemble your query using Python's string operations because doing so
+is insecure; it makes your program vulnerable to an SQL injection attack.
+
+Instead, use the DB-API's parameter substitution. Put ``?`` as a placeholder
+wherever you want to use a value, and then provide a tuple of values as the
+second argument to the cursor's :meth:`~Cursor.execute` method. (Other database modules
+may use a different placeholder, such as ``%s`` or ``:1``.) For example::
+
+ # Never do this -- insecure!
+ symbol = 'IBM'
+ c.execute("... where symbol = '%s'" % symbol)
+
+ # Do this instead
+ t = (symbol,)
+ c.execute('select * from stocks where symbol=?', t)
+
+ # Larger example
+ for t in [('2006-03-28', 'BUY', 'IBM', 1000, 45.00),
+ ('2006-04-05', 'BUY', 'MSOFT', 1000, 72.00),
+ ('2006-04-06', 'SELL', 'IBM', 500, 53.00),
+ ]:
+ c.execute('insert into stocks values (?,?,?,?,?)', t)
+
+To retrieve data after executing a SELECT statement, you can either treat the
+cursor as an :term:`iterator`, call the cursor's :meth:`~Cursor.fetchone` method to
+retrieve a single matching row, or call :meth:`~Cursor.fetchall` to get a list of the
+matching rows.
+
+This example uses the iterator form::
+
+ >>> c = conn.cursor()
+ >>> c.execute('select * from stocks order by price')
+ >>> for row in c:
+ ... print row
+ ...
+ (u'2006-01-05', u'BUY', u'RHAT', 100, 35.140000000000001)
+ (u'2006-03-28', u'BUY', u'IBM', 1000, 45.0)
+ (u'2006-04-06', u'SELL', u'IBM', 500, 53.0)
+ (u'2006-04-05', u'BUY', u'MSOFT', 1000, 72.0)
+ >>>
+
+
+.. seealso::
+
+ http://www.pysqlite.org
+ The pysqlite web page.
+
+ http://www.sqlite.org
+ The SQLite web page; the documentation describes the syntax and the available
+ data types for the supported SQL dialect.
+
+ :pep:`249` - Database API Specification 2.0
+ PEP written by Marc-André Lemburg.
+
+
+.. _sqlite3-module-contents:
+
+Module functions and constants
+------------------------------
+
+
+.. data:: PARSE_DECLTYPES
+
+ This constant is meant to be used with the *detect_types* parameter of the
+ :func:`connect` function.
+
+ Setting it makes the :mod:`sqlite3` module parse the declared type for each
+ column it returns. It will parse out the first word of the declared type,
+ i. e. for "integer primary key", it will parse out "integer", or for
+ "number(10)" it will parse out "number". Then for that column, it will look
+ into the converters dictionary and use the converter function registered for
+ that type there.
+
+
+.. data:: PARSE_COLNAMES
+
+ This constant is meant to be used with the *detect_types* parameter of the
+ :func:`connect` function.
+
+ Setting this makes the SQLite interface parse the column name for each column it
+ returns. It will look for a string formed [mytype] in there, and then decide
+ that 'mytype' is the type of the column. It will try to find an entry of
+ 'mytype' in the converters dictionary and then use the converter function found
+ there to return the value. The column name found in :attr:`Cursor.description`
+ is only the first word of the column name, i. e. if you use something like
+ ``'as "x [datetime]"'`` in your SQL, then we will parse out everything until the
+ first blank for the column name: the column name would simply be "x".
+
+
+.. function:: connect(database[, timeout, isolation_level, detect_types, factory])
+
+ Opens a connection to the SQLite database file *database*. You can use
+ ``":memory:"`` to open a database connection to a database that resides in RAM
+ instead of on disk.
+
+ When a database is accessed by multiple connections, and one of the processes
+ modifies the database, the SQLite database is locked until that transaction is
+ committed. The *timeout* parameter specifies how long the connection should wait
+ for the lock to go away until raising an exception. The default for the timeout
+ parameter is 5.0 (five seconds).
+
+ For the *isolation_level* parameter, please see the
+ :attr:`Connection.isolation_level` property of :class:`Connection` objects.
+
+ SQLite natively supports only the types TEXT, INTEGER, FLOAT, BLOB and NULL. If
+ you want to use other types you must add support for them yourself. The
+ *detect_types* parameter and the using custom **converters** registered with the
+ module-level :func:`register_converter` function allow you to easily do that.
+
+ *detect_types* defaults to 0 (i. e. off, no type detection), you can set it to
+ any combination of :const:`PARSE_DECLTYPES` and :const:`PARSE_COLNAMES` to turn
+ type detection on.
+
+ By default, the :mod:`sqlite3` module uses its :class:`Connection` class for the
+ connect call. You can, however, subclass the :class:`Connection` class and make
+ :func:`connect` use your class instead by providing your class for the *factory*
+ parameter.
+
+ Consult the section :ref:`sqlite3-types` of this manual for details.
+
+ The :mod:`sqlite3` module internally uses a statement cache to avoid SQL parsing
+ overhead. If you want to explicitly set the number of statements that are cached
+ for the connection, you can set the *cached_statements* parameter. The currently
+ implemented default is to cache 100 statements.
+
+
+.. function:: register_converter(typename, callable)
+
+ Registers a callable to convert a bytestring from the database into a custom
+ Python type. The callable will be invoked for all database values that are of
+ the type *typename*. Confer the parameter *detect_types* of the :func:`connect`
+ function for how the type detection works. Note that the case of *typename* and
+ the name of the type in your query must match!
+
+
+.. function:: register_adapter(type, callable)
+
+ Registers a callable to convert the custom Python type *type* into one of
+ SQLite's supported types. The callable *callable* accepts as single parameter
+ the Python value, and must return a value of the following types: int, long,
+ float, str (UTF-8 encoded), unicode or buffer.
+
+
+.. function:: complete_statement(sql)
+
+ Returns :const:`True` if the string *sql* contains one or more complete SQL
+ statements terminated by semicolons. It does not verify that the SQL is
+ syntactically correct, only that there are no unclosed string literals and the
+ statement is terminated by a semicolon.
+
+ This can be used to build a shell for SQLite, as in the following example:
+
+
+ .. literalinclude:: ../includes/sqlite3/complete_statement.py
+
+
+.. function:: enable_callback_tracebacks(flag)
+
+ By default you will not get any tracebacks in user-defined functions,
+ aggregates, converters, authorizer callbacks etc. If you want to debug them, you
+ can call this function with *flag* as True. Afterwards, you will get tracebacks
+ from callbacks on ``sys.stderr``. Use :const:`False` to disable the feature
+ again.
+
+
+.. _sqlite3-connection-objects:
+
+Connection Objects
+------------------
+
+.. class:: Connection
+
+ A SQLite database connection has the following attributes and methods:
+
+.. attribute:: Connection.isolation_level
+
+ Get or set the current isolation level. :const:`None` for autocommit mode or one of
+ "DEFERRED", "IMMEDIATE" or "EXLUSIVE". See section
+ :ref:`sqlite3-controlling-transactions` for a more detailed explanation.
+
+
+.. method:: Connection.cursor([cursorClass])
+
+ The cursor method accepts a single optional parameter *cursorClass*. If
+ supplied, this must be a custom cursor class that extends
+ :class:`sqlite3.Cursor`.
+
+
+.. method:: Connection.commit()
+
+ This method commits the current transaction. If you don't call this method,
+ anything you did since the last call to ``commit()`` is not visible from from
+ other database connections. If you wonder why you don't see the data you've
+ written to the database, please check you didn't forget to call this method.
+
+.. method:: Connection.rollback()
+
+ This method rolls back any changes to the database since the last call to
+ :meth:`commit`.
+
+.. method:: Connection.close()
+
+ This closes the database connection. Note that this does not automatically
+ call :meth:`commit`. If you just close your database connection without
+ calling :meth:`commit` first, your changes will be lost!
+
+.. method:: Connection.execute(sql, [parameters])
+
+ This is a nonstandard shortcut that creates an intermediate cursor object by
+ calling the cursor method, then calls the cursor's :meth:`execute` method with
+ the parameters given.
+
+
+.. method:: Connection.executemany(sql, [parameters])
+
+ This is a nonstandard shortcut that creates an intermediate cursor object by
+ calling the cursor method, then calls the cursor's :meth:`executemany` method
+ with the parameters given.
+
+.. method:: Connection.executescript(sql_script)
+
+ This is a nonstandard shortcut that creates an intermediate cursor object by
+ calling the cursor method, then calls the cursor's :meth:`executescript` method
+ with the parameters given.
+
+
+.. method:: Connection.create_function(name, num_params, func)
+
+ Creates a user-defined function that you can later use from within SQL
+ statements under the function name *name*. *num_params* is the number of
+ parameters the function accepts, and *func* is a Python callable that is called
+ as the SQL function.
+
+ The function can return any of the types supported by SQLite: unicode, str, int,
+ long, float, buffer and None.
+
+ Example:
+
+ .. literalinclude:: ../includes/sqlite3/md5func.py
+
+
+.. method:: Connection.create_aggregate(name, num_params, aggregate_class)
+
+ Creates a user-defined aggregate function.
+
+ The aggregate class must implement a ``step`` method, which accepts the number
+ of parameters *num_params*, and a ``finalize`` method which will return the
+ final result of the aggregate.
+
+ The ``finalize`` method can return any of the types supported by SQLite:
+ unicode, str, int, long, float, buffer and None.
+
+ Example:
+
+ .. literalinclude:: ../includes/sqlite3/mysumaggr.py
+
+
+.. method:: Connection.create_collation(name, callable)
+
+ Creates a collation with the specified *name* and *callable*. The callable will
+ be passed two string arguments. It should return -1 if the first is ordered
+ lower than the second, 0 if they are ordered equal and 1 if the first is ordered
+ higher than the second. Note that this controls sorting (ORDER BY in SQL) so
+ your comparisons don't affect other SQL operations.
+
+ Note that the callable will get its parameters as Python bytestrings, which will
+ normally be encoded in UTF-8.
+
+ The following example shows a custom collation that sorts "the wrong way":
+
+ .. literalinclude:: ../includes/sqlite3/collation_reverse.py
+
+ To remove a collation, call ``create_collation`` with None as callable::
+
+ con.create_collation("reverse", None)
+
+
+.. method:: Connection.interrupt()
+
+ You can call this method from a different thread to abort any queries that might
+ be executing on the connection. The query will then abort and the caller will
+ get an exception.
+
+
+.. method:: Connection.set_authorizer(authorizer_callback)
+
+ This routine registers a callback. The callback is invoked for each attempt to
+ access a column of a table in the database. The callback should return
+ :const:`SQLITE_OK` if access is allowed, :const:`SQLITE_DENY` if the entire SQL
+ statement should be aborted with an error and :const:`SQLITE_IGNORE` if the
+ column should be treated as a NULL value. These constants are available in the
+ :mod:`sqlite3` module.
+
+ The first argument to the callback signifies what kind of operation is to be
+ authorized. The second and third argument will be arguments or :const:`None`
+ depending on the first argument. The 4th argument is the name of the database
+ ("main", "temp", etc.) if applicable. The 5th argument is the name of the
+ inner-most trigger or view that is responsible for the access attempt or
+ :const:`None` if this access attempt is directly from input SQL code.
+
+ Please consult the SQLite documentation about the possible values for the first
+ argument and the meaning of the second and third argument depending on the first
+ one. All necessary constants are available in the :mod:`sqlite3` module.
+
+
+.. method:: Connection.set_progress_handler(handler, n)
+
+ .. versionadded:: 2.6
+
+ This routine registers a callback. The callback is invoked for every *n*
+ instructions of the SQLite virtual machine. This is useful if you want to
+ get called from SQLite during long-running operations, for example to update
+ a GUI.
+
+ If you want to clear any previously installed progress handler, call the
+ method with :const:`None` for *handler*.
+
+
+.. attribute:: Connection.row_factory
+
+ You can change this attribute to a callable that accepts the cursor and the
+ original row as a tuple and will return the real result row. This way, you can
+ implement more advanced ways of returning results, such as returning an object
+ that can also access columns by name.
+
+ Example:
+
+ .. literalinclude:: ../includes/sqlite3/row_factory.py
+
+ If returning a tuple doesn't suffice and you want name-based access to
+ columns, you should consider setting :attr:`row_factory` to the
+ highly-optimized :class:`sqlite3.Row` type. :class:`Row` provides both
+ index-based and case-insensitive name-based access to columns with almost no
+ memory overhead. It will probably be better than your own custom
+ dictionary-based approach or even a db_row based solution.
+
+ .. XXX what's a db_row-based solution?
+
+
+.. attribute:: Connection.text_factory
+
+ Using this attribute you can control what objects are returned for the ``TEXT``
+ data type. By default, this attribute is set to :class:`unicode` and the
+ :mod:`sqlite3` module will return Unicode objects for ``TEXT``. If you want to
+ return bytestrings instead, you can set it to :class:`str`.
+
+ For efficiency reasons, there's also a way to return Unicode objects only for
+ non-ASCII data, and bytestrings otherwise. To activate it, set this attribute to
+ :const:`sqlite3.OptimizedUnicode`.
+
+ You can also set it to any other callable that accepts a single bytestring
+ parameter and returns the resulting object.
+
+ See the following example code for illustration:
+
+ .. literalinclude:: ../includes/sqlite3/text_factory.py
+
+
+.. attribute:: Connection.total_changes
+
+ Returns the total number of database rows that have been modified, inserted, or
+ deleted since the database connection was opened.
+
+
+.. attribute:: Connection.iterdump
+
+ Returns an iterator to dump the database in an SQL text format. Useful when
+ saving an in-memory database for later restoration. This function provides
+ the same capabilities as the :kbd:`.dump` command in the :program:`sqlite3`
+ shell.
+
+ .. versionadded:: 2.6
+
+ Example::
+
+ # Convert file existing_db.db to SQL dump file dump.sql
+ import sqlite3, os
+
+ con = sqlite3.connect('existing_db.db')
+ with open('dump.sql', 'w') as f:
+ for line in con.iterdump():
+ f.write('%s\n' % line)
+
+
+.. _sqlite3-cursor-objects:
+
+Cursor Objects
+--------------
+
+.. class:: Cursor
+
+ A SQLite database cursor has the following attributes and methods:
+
+.. method:: Cursor.execute(sql, [parameters])
+
+ Executes an SQL statement. The SQL statement may be parametrized (i. e.
+ placeholders instead of SQL literals). The :mod:`sqlite3` module supports two
+ kinds of placeholders: question marks (qmark style) and named placeholders
+ (named style).
+
+ This example shows how to use parameters with qmark style:
+
+ .. literalinclude:: ../includes/sqlite3/execute_1.py
+
+ This example shows how to use the named style:
+
+ .. literalinclude:: ../includes/sqlite3/execute_2.py
+
+ :meth:`execute` will only execute a single SQL statement. If you try to execute
+ more than one statement with it, it will raise a Warning. Use
+ :meth:`executescript` if you want to execute multiple SQL statements with one
+ call.
+
+
+.. method:: Cursor.executemany(sql, seq_of_parameters)
+
+ Executes an SQL command against all parameter sequences or mappings found in
+ the sequence *sql*. The :mod:`sqlite3` module also allows using an
+ :term:`iterator` yielding parameters instead of a sequence.
+
+ .. literalinclude:: ../includes/sqlite3/executemany_1.py
+
+ Here's a shorter example using a :term:`generator`:
+
+ .. literalinclude:: ../includes/sqlite3/executemany_2.py
+
+
+.. method:: Cursor.executescript(sql_script)
+
+ This is a nonstandard convenience method for executing multiple SQL statements
+ at once. It issues a ``COMMIT`` statement first, then executes the SQL script it
+ gets as a parameter.
+
+ *sql_script* can be a bytestring or a Unicode string.
+
+ Example:
+
+ .. literalinclude:: ../includes/sqlite3/executescript.py
+
+
+.. method:: Cursor.fetchone()
+
+ Fetches the next row of a query result set, returning a single sequence,
+ or :const:`None` when no more data is available.
+
+
+.. method:: Cursor.fetchmany([size=cursor.arraysize])
+
+ Fetches the next set of rows of a query result, returning a list. An empty
+ list is returned when no more rows are available.
+
+ The number of rows to fetch per call is specified by the *size* parameter.
+ If it is not given, the cursor's arraysize determines the number of rows
+ to be fetched. The method should try to fetch as many rows as indicated by
+ the size parameter. If this is not possible due to the specified number of
+ rows not being available, fewer rows may be returned.
+
+ Note there are performance considerations involved with the *size* parameter.
+ For optimal performance, it is usually best to use the arraysize attribute.
+ If the *size* parameter is used, then it is best for it to retain the same
+ value from one :meth:`fetchmany` call to the next.
+
+.. method:: Cursor.fetchall()
+
+ Fetches all (remaining) rows of a query result, returning a list. Note that
+ the cursor's arraysize attribute can affect the performance of this operation.
+ An empty list is returned when no rows are available.
+
+
+.. attribute:: Cursor.rowcount
+
+ Although the :class:`Cursor` class of the :mod:`sqlite3` module implements this
+ attribute, the database engine's own support for the determination of "rows
+ affected"/"rows selected" is quirky.
+
+ For ``DELETE`` statements, SQLite reports :attr:`rowcount` as 0 if you make a
+ ``DELETE FROM table`` without any condition.
+
+ For :meth:`executemany` statements, the number of modifications are summed up
+ into :attr:`rowcount`.
+
+ As required by the Python DB API Spec, the :attr:`rowcount` attribute "is -1 in
+ case no ``executeXX()`` has been performed on the cursor or the rowcount of the
+ last operation is not determinable by the interface".
+
+ This includes ``SELECT`` statements because we cannot determine the number of
+ rows a query produced until all rows were fetched.
+
+.. attribute:: Cursor.lastrowid
+
+ This read-only attribute provides the rowid of the last modified row. It is
+ only set if you issued a ``INSERT`` statement using the :meth:`execute`
+ method. For operations other than ``INSERT`` or when :meth:`executemany` is
+ called, :attr:`lastrowid` is set to :const:`None`.
+
+.. attribute:: Cursor.description
+
+ This read-only attribute provides the column names of the last query. To
+ remain compatible with the Python DB API, it returns a 7-tuple for each
+ column where the last six items of each tuple are :const:`None`.
+
+ It is set for ``SELECT`` statements without any matching rows as well.
+
+.. _sqlite3-row-objects:
+
+Row Objects
+-----------
+
+.. class:: Row
+
+ A :class:`Row` instance serves as a highly optimized
+ :attr:`~Connection.row_factory` for :class:`Connection` objects.
+ It tries to mimic a tuple in most of its features.
+
+ It supports mapping access by column name and index, iteration,
+ representation, equality testing and :func:`len`.
+
+ If two :class:`Row` objects have exactly the same columns and their
+ members are equal, they compare equal.
+
+ .. versionchanged:: 2.6
+ Added iteration and equality (hashability).
+
+ .. method:: keys
+
+ This method returns a tuple of column names. Immediately after a query,
+ it is the first member of each tuple in :attr:`Cursor.description`.
+
+ .. versionadded:: 2.6
+
+Let's assume we initialize a table as in the example given above::
+
+ conn = sqlite3.connect(":memory:")
+ c = conn.cursor()
+ c.execute('''create table stocks
+ (date text, trans text, symbol text,
+ qty real, price real)''')
+ c.execute("""insert into stocks
+ values ('2006-01-05','BUY','RHAT',100,35.14)""")
+ conn.commit()
+ c.close()
+
+Now we plug :class:`Row` in::
+
+ >>> conn.row_factory = sqlite3.Row
+ >>> c = conn.cursor()
+ >>> c.execute('select * from stocks')
+ <sqlite3.Cursor object at 0x7f4e7dd8fa80>
+ >>> r = c.fetchone()
+ >>> type(r)
+ <type 'sqlite3.Row'>
+ >>> r
+ (u'2006-01-05', u'BUY', u'RHAT', 100.0, 35.140000000000001)
+ >>> len(r)
+ 5
+ >>> r[2]
+ u'RHAT'
+ >>> r.keys()
+ ['date', 'trans', 'symbol', 'qty', 'price']
+ >>> r['qty']
+ 100.0
+ >>> for member in r: print member
+ ...
+ 2006-01-05
+ BUY
+ RHAT
+ 100.0
+ 35.14
+
+
+.. _sqlite3-types:
+
+SQLite and Python types
+-----------------------
+
+
+Introduction
+^^^^^^^^^^^^
+
+SQLite natively supports the following types: ``NULL``, ``INTEGER``,
+``REAL``, ``TEXT``, ``BLOB``.
+
+The following Python types can thus be sent to SQLite without any problem:
+
++-----------------------------+-------------+
+| Python type | SQLite type |
++=============================+=============+
+| :const:`None` | ``NULL`` |
++-----------------------------+-------------+
+| :class:`int` | ``INTEGER`` |
++-----------------------------+-------------+
+| :class:`long` | ``INTEGER`` |
++-----------------------------+-------------+
+| :class:`float` | ``REAL`` |
++-----------------------------+-------------+
+| :class:`str` (UTF8-encoded) | ``TEXT`` |
++-----------------------------+-------------+
+| :class:`unicode` | ``TEXT`` |
++-----------------------------+-------------+
+| :class:`buffer` | ``BLOB`` |
++-----------------------------+-------------+
+
+This is how SQLite types are converted to Python types by default:
+
++-------------+----------------------------------------------+
+| SQLite type | Python type |
++=============+==============================================+
+| ``NULL`` | :const:`None` |
++-------------+----------------------------------------------+
+| ``INTEGER`` | :class:`int` or :class:`long`, |
+| | depending on size |
++-------------+----------------------------------------------+
+| ``REAL`` | :class:`float` |
++-------------+----------------------------------------------+
+| ``TEXT`` | depends on :attr:`~Connection.text_factory`, |
+| | :class:`unicode` by default |
++-------------+----------------------------------------------+
+| ``BLOB`` | :class:`buffer` |
++-------------+----------------------------------------------+
+
+The type system of the :mod:`sqlite3` module is extensible in two ways: you can
+store additional Python types in a SQLite database via object adaptation, and
+you can let the :mod:`sqlite3` module convert SQLite types to different Python
+types via converters.
+
+
+Using adapters to store additional Python types in SQLite databases
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+As described before, SQLite supports only a limited set of types natively. To
+use other Python types with SQLite, you must **adapt** them to one of the
+sqlite3 module's supported types for SQLite: one of NoneType, int, long, float,
+str, unicode, buffer.
+
+The :mod:`sqlite3` module uses Python object adaptation, as described in
+:pep:`246` for this. The protocol to use is :class:`PrepareProtocol`.
+
+There are two ways to enable the :mod:`sqlite3` module to adapt a custom Python
+type to one of the supported ones.
+
+
+Letting your object adapt itself
+""""""""""""""""""""""""""""""""
+
+This is a good approach if you write the class yourself. Let's suppose you have
+a class like this::
+
+ class Point(object):
+ def __init__(self, x, y):
+ self.x, self.y = x, y
+
+Now you want to store the point in a single SQLite column. First you'll have to
+choose one of the supported types first to be used for representing the point.
+Let's just use str and separate the coordinates using a semicolon. Then you need
+to give your class a method ``__conform__(self, protocol)`` which must return
+the converted value. The parameter *protocol* will be :class:`PrepareProtocol`.
+
+.. literalinclude:: ../includes/sqlite3/adapter_point_1.py
+
+
+Registering an adapter callable
+"""""""""""""""""""""""""""""""
+
+The other possibility is to create a function that converts the type to the
+string representation and register the function with :meth:`register_adapter`.
+
+.. note::
+
+ The type/class to adapt must be a :term:`new-style class`, i. e. it must have
+ :class:`object` as one of its bases.
+
+.. literalinclude:: ../includes/sqlite3/adapter_point_2.py
+
+The :mod:`sqlite3` module has two default adapters for Python's built-in
+:class:`datetime.date` and :class:`datetime.datetime` types. Now let's suppose
+we want to store :class:`datetime.datetime` objects not in ISO representation,
+but as a Unix timestamp.
+
+.. literalinclude:: ../includes/sqlite3/adapter_datetime.py
+
+
+Converting SQLite values to custom Python types
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Writing an adapter lets you send custom Python types to SQLite. But to make it
+really useful we need to make the Python to SQLite to Python roundtrip work.
+
+Enter converters.
+
+Let's go back to the :class:`Point` class. We stored the x and y coordinates
+separated via semicolons as strings in SQLite.
+
+First, we'll define a converter function that accepts the string as a parameter
+and constructs a :class:`Point` object from it.
+
+.. note::
+
+ Converter functions **always** get called with a string, no matter under which
+ data type you sent the value to SQLite.
+
+::
+
+ def convert_point(s):
+ x, y = map(float, s.split(";"))
+ return Point(x, y)
+
+Now you need to make the :mod:`sqlite3` module know that what you select from
+the database is actually a point. There are two ways of doing this:
+
+* Implicitly via the declared type
+
+* Explicitly via the column name
+
+Both ways are described in section :ref:`sqlite3-module-contents`, in the entries
+for the constants :const:`PARSE_DECLTYPES` and :const:`PARSE_COLNAMES`.
+
+The following example illustrates both approaches.
+
+.. literalinclude:: ../includes/sqlite3/converter_point.py
+
+
+Default adapters and converters
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+There are default adapters for the date and datetime types in the datetime
+module. They will be sent as ISO dates/ISO timestamps to SQLite.
+
+The default converters are registered under the name "date" for
+:class:`datetime.date` and under the name "timestamp" for
+:class:`datetime.datetime`.
+
+This way, you can use date/timestamps from Python without any additional
+fiddling in most cases. The format of the adapters is also compatible with the
+experimental SQLite date/time functions.
+
+The following example demonstrates this.
+
+.. literalinclude:: ../includes/sqlite3/pysqlite_datetime.py
+
+
+.. _sqlite3-controlling-transactions:
+
+Controlling Transactions
+------------------------
+
+By default, the :mod:`sqlite3` module opens transactions implicitly before a
+Data Modification Language (DML) statement (i.e.
+``INSERT``/``UPDATE``/``DELETE``/``REPLACE``), and commits transactions
+implicitly before a non-DML, non-query statement (i. e.
+anything other than ``SELECT`` or the aforementioned).
+
+So if you are within a transaction and issue a command like ``CREATE TABLE
+...``, ``VACUUM``, ``PRAGMA``, the :mod:`sqlite3` module will commit implicitly
+before executing that command. There are two reasons for doing that. The first
+is that some of these commands don't work within transactions. The other reason
+is that pysqlite needs to keep track of the transaction state (if a transaction
+is active or not).
+
+You can control which kind of ``BEGIN`` statements pysqlite implicitly executes
+(or none at all) via the *isolation_level* parameter to the :func:`connect`
+call, or via the :attr:`isolation_level` property of connections.
+
+If you want **autocommit mode**, then set :attr:`isolation_level` to None.
+
+Otherwise leave it at its default, which will result in a plain "BEGIN"
+statement, or set it to one of SQLite's supported isolation levels: "DEFERRED",
+"IMMEDIATE" or "EXCLUSIVE".
+
+
+
+Using pysqlite efficiently
+--------------------------
+
+
+Using shortcut methods
+^^^^^^^^^^^^^^^^^^^^^^
+
+Using the nonstandard :meth:`execute`, :meth:`executemany` and
+:meth:`executescript` methods of the :class:`Connection` object, your code can
+be written more concisely because you don't have to create the (often
+superfluous) :class:`Cursor` objects explicitly. Instead, the :class:`Cursor`
+objects are created implicitly and these shortcut methods return the cursor
+objects. This way, you can execute a ``SELECT`` statement and iterate over it
+directly using only a single call on the :class:`Connection` object.
+
+.. literalinclude:: ../includes/sqlite3/shortcut_methods.py
+
+
+Accessing columns by name instead of by index
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+One useful feature of the :mod:`sqlite3` module is the builtin
+:class:`sqlite3.Row` class designed to be used as a row factory.
+
+Rows wrapped with this class can be accessed both by index (like tuples) and
+case-insensitively by name:
+
+.. literalinclude:: ../includes/sqlite3/rowclass.py
+
+
+Using the connection as a context manager
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. versionadded:: 2.6
+
+Connection objects can be used as context managers
+that automatically commit or rollback transactions. In the event of an
+exception, the transaction is rolled back; otherwise, the transaction is
+committed:
+
+.. literalinclude:: ../includes/sqlite3/ctx_manager.py