dblite.engines.sqlite.Transaction Class Reference

Transaction context manager, breakable by raising Rollback. More...

Inheritance diagram for dblite.engines.sqlite.Transaction:

Public Member Functions
def	__init__ (self, db, commit=True, exclusive=True, **__)
	Creates a new transaction. More...
def	__enter__ (self)
	Context manager entry, opens cursor, returns Transaction object. More...
def	__exit__ (self, exc_type, exc_val, exc_trace)
	Context manager exit, closes cursor, commits or rolls back as specified on creation. More...
def	close (self, commit=None)
	Closes the transaction, performing commit or rollback as specified. More...
def	commit (self)
	Commits pending actions, if any. More...
def	execute (self, sql, args=())
	Executes the SQL statement and returns sqlite3.Cursor. More...
def	executemany (self, sql, args)
	Executes the SQL statement against all parameter sequences. More...
def	executescript (self, sql)
	Executes the SQL as script of any number of statements, outside of transaction. More...
def	rollback (self)
	Rolls back pending actions, if any. More...
Public Member Functions inherited from dblite.api.Transaction
def	__del__ (self)
	Closes the transaction, if open. More...
Public Member Functions inherited from dblite.api.Queryable
def	delete (self, table, where=(), **kwargs)
	Convenience wrapper for database DELETE, returns affected row count. More...
def	fetchall (self, table, cols="*", where=(), group=(), order=(), limit=(), **kwargs)
	Convenience wrapper for database SELECT and fetch all. More...
def	fetchone (self, table, cols="*", where=(), group=(), order=(), limit=(), **kwargs)
	Convenience wrapper for database SELECT and fetch one. More...
def	select (self, table, cols="*", where=(), group=(), order=(), limit=(), **kwargs)
	Convenience wrapper for database SELECT, returns database cursor. More...
def	update (self, table, values, where=(), **kwargs)
	Convenience wrapper for database UPDATE, returns affected row count. More...
Public Member Functions inherited from dblite.engines.sqlite.Queryable
def	insert (self, table, values=(), **kwargs)
	Convenience wrapper for database INSERT, returns inserted row ID. More...
def	insertmany (self, table, rows=(), **kwargs)
	Convenience wrapper for database multiple INSERTs, returns list of inserted row IDs. More...
def	makeSQL (self, action, table, cols="*", where=(), group=(), order=(), limit=(), values=(), kwargs=None)
	Returns (SQL statement string, parameter dict). More...
def	quote (cls, value, force=False)
	Returns identifier in quotes and proper-escaped for queries, if value needs quoting (has non-alphanumerics, starts with number, or is reserved). More...

Properties
	closed = property
	Whether transaction is currently not open. More...
	cursor = property
	Database engine cursor object, or `None` if closed. More...
	database = property
	Returns transaction Database instance. More...
Properties inherited from dblite.api.Transaction
	database = property
	Returns transaction Database instance. More...
Properties inherited from dblite.api.Queryable
	closed = property
	Whether currently not open. More...
	cursor = property
	Database engine cursor object, or `None` if closed. More...

Additional Inherited Members
Static Public Attributes inherited from dblite.api.Queryable
	ENGINE = None
	Underlying database engine, "sqlite" for SQLite3 and "postgres" for PostgreSQL. More...
Static Public Attributes inherited from dblite.engines.sqlite.Queryable
string	ENGINE = "sqlite"
	Name of underlying database engine. More...
list	OPS
	Recognized binary operators for makeSQL() More...

Detailed Description

Transaction context manager, breakable by raising Rollback.

Note that in SQLite, a single connection has one shared transaction state, so it is highly recommended to use exclusive Transaction instances for any action queries, as concurrent transactions can interfere with one another otherwise.

Definition at line 418 of file sqlite.py.

Constructor & Destructor Documentation

__init__()

def dblite.engines.sqlite.Transaction.__init__	(		self,
			db,
			commit = True,
			exclusive = True,
		**	__
	)

Creates a new transaction.

Parameters

db	Database instance
commit	whether transaction commits automatically at exiting with-block
exclusive	whether entering a with-block is exclusive over other Transaction instances on this Database

Reimplemented from dblite.api.Transaction.

Definition at line 427 of file sqlite.py.

Member Function Documentation

__enter__()

def dblite.engines.sqlite.Transaction.__enter__

(

self

)

Context manager entry, opens cursor, returns Transaction object.

Reimplemented from dblite.api.Transaction.

Definition at line 435 of file sqlite.py.

__exit__()

def dblite.engines.sqlite.Transaction.__exit__	(		self,
			exc_type,
			exc_val,
			exc_trace
	)

Context manager exit, closes cursor, commits or rolls back as specified on creation.

Reimplemented from dblite.api.Transaction.

Definition at line 447 of file sqlite.py.

close()

def dblite.engines.sqlite.Transaction.close	(		self,
			commit = None
	)

Closes the transaction, performing commit or rollback as specified.

Parameters

commit

`True` for final commit, `False` for rollback, `None` for auto-commit, if any

Reimplemented from dblite.api.Transaction.

Definition at line 466 of file sqlite.py.

commit()

def dblite.engines.sqlite.Transaction.commit

(

self

)

Commits pending actions, if any.

Reimplemented from dblite.api.Transaction.

Definition at line 511 of file sqlite.py.

execute()

def dblite.engines.sqlite.Transaction.execute	(		self,
			sql,
			args = ()
	)

Executes the SQL statement and returns sqlite3.Cursor.

Parameters

sql	SQL statement to execute, with SQLite-specific parameter bindings, if any
args	dictionary for :name placeholders, or a sequence for positional ? placeholders

Reimplemented from dblite.api.Queryable.

Definition at line 482 of file sqlite.py.

executemany()

def dblite.engines.sqlite.Transaction.executemany	(		self,
			sql,
			args
	)

Executes the SQL statement against all parameter sequences.

Parameters

sql	SQL statement to execute, with SQLite-specific parameter bindings
args	iterable of query parameters, as dictionaries for :name placeholders or sequences for positional ? placeholders

Reimplemented from dblite.api.Queryable.

Definition at line 493 of file sqlite.py.

executescript()

def dblite.engines.sqlite.Transaction.executescript	(		self,
			sql
	)

Executes the SQL as script of any number of statements, outside of transaction.

Any pending transaction will be committed first.

Parameters

sql	script with one or more SQL statements

Reimplemented from dblite.api.Queryable.

Definition at line 505 of file sqlite.py.

rollback()

def dblite.engines.sqlite.Transaction.rollback

(

self

)

Rolls back pending actions, if any.

Reimplemented from dblite.api.Transaction.

Definition at line 517 of file sqlite.py.

Property Documentation

closed

dblite.engines.sqlite.Transaction.closed = property

static

Whether transaction is currently not open.

Definition at line 525 of file sqlite.py.

cursor

dblite.engines.sqlite.Transaction.cursor = property

static

Database engine cursor object, or `None` if closed.

Definition at line 532 of file sqlite.py.

database

dblite.engines.sqlite.Transaction.database = property

static

Returns transaction Database instance.

Definition at line 542 of file sqlite.py.

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The documentation for this class was generated from the following file:

• dblite/engines/sqlite.py