mirror of
https://github.com/moparisthebest/SickRage
synced 2024-11-17 23:05:11 -05:00
865 lines
28 KiB
Python
865 lines
28 KiB
Python
# sql/ddl.py
|
|
# Copyright (C) 2009-2014 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
|
|
"""
|
|
Provides the hierarchy of DDL-defining schema items as well as routines
|
|
to invoke them for a create/drop call.
|
|
|
|
"""
|
|
|
|
from .. import util
|
|
from .elements import ClauseElement
|
|
from .visitors import traverse
|
|
from .base import Executable, _generative, SchemaVisitor, _bind_or_error
|
|
from ..util import topological
|
|
from .. import event
|
|
from .. import exc
|
|
|
|
class _DDLCompiles(ClauseElement):
|
|
def _compiler(self, dialect, **kw):
|
|
"""Return a compiler appropriate for this ClauseElement, given a
|
|
Dialect."""
|
|
|
|
return dialect.ddl_compiler(dialect, self, **kw)
|
|
|
|
|
|
class DDLElement(Executable, _DDLCompiles):
|
|
"""Base class for DDL expression constructs.
|
|
|
|
This class is the base for the general purpose :class:`.DDL` class,
|
|
as well as the various create/drop clause constructs such as
|
|
:class:`.CreateTable`, :class:`.DropTable`, :class:`.AddConstraint`,
|
|
etc.
|
|
|
|
:class:`.DDLElement` integrates closely with SQLAlchemy events,
|
|
introduced in :ref:`event_toplevel`. An instance of one is
|
|
itself an event receiving callable::
|
|
|
|
event.listen(
|
|
users,
|
|
'after_create',
|
|
AddConstraint(constraint).execute_if(dialect='postgresql')
|
|
)
|
|
|
|
.. seealso::
|
|
|
|
:class:`.DDL`
|
|
|
|
:class:`.DDLEvents`
|
|
|
|
:ref:`event_toplevel`
|
|
|
|
:ref:`schema_ddl_sequences`
|
|
|
|
"""
|
|
|
|
_execution_options = Executable.\
|
|
_execution_options.union({'autocommit': True})
|
|
|
|
target = None
|
|
on = None
|
|
dialect = None
|
|
callable_ = None
|
|
|
|
def _execute_on_connection(self, connection, multiparams, params):
|
|
return connection._execute_ddl(self, multiparams, params)
|
|
|
|
def execute(self, bind=None, target=None):
|
|
"""Execute this DDL immediately.
|
|
|
|
Executes the DDL statement in isolation using the supplied
|
|
:class:`.Connectable` or
|
|
:class:`.Connectable` assigned to the ``.bind``
|
|
property, if not supplied. If the DDL has a conditional ``on``
|
|
criteria, it will be invoked with None as the event.
|
|
|
|
:param bind:
|
|
Optional, an ``Engine`` or ``Connection``. If not supplied, a valid
|
|
:class:`.Connectable` must be present in the
|
|
``.bind`` property.
|
|
|
|
:param target:
|
|
Optional, defaults to None. The target SchemaItem for the
|
|
execute call. Will be passed to the ``on`` callable if any,
|
|
and may also provide string expansion data for the
|
|
statement. See ``execute_at`` for more information.
|
|
|
|
"""
|
|
|
|
if bind is None:
|
|
bind = _bind_or_error(self)
|
|
|
|
if self._should_execute(target, bind):
|
|
return bind.execute(self.against(target))
|
|
else:
|
|
bind.engine.logger.info(
|
|
"DDL execution skipped, criteria not met.")
|
|
|
|
@util.deprecated("0.7", "See :class:`.DDLEvents`, as well as "
|
|
":meth:`.DDLElement.execute_if`.")
|
|
def execute_at(self, event_name, target):
|
|
"""Link execution of this DDL to the DDL lifecycle of a SchemaItem.
|
|
|
|
Links this ``DDLElement`` to a ``Table`` or ``MetaData`` instance,
|
|
executing it when that schema item is created or dropped. The DDL
|
|
statement will be executed using the same Connection and transactional
|
|
context as the Table create/drop itself. The ``.bind`` property of
|
|
this statement is ignored.
|
|
|
|
:param event:
|
|
One of the events defined in the schema item's ``.ddl_events``;
|
|
e.g. 'before-create', 'after-create', 'before-drop' or 'after-drop'
|
|
|
|
:param target:
|
|
The Table or MetaData instance for which this DDLElement will
|
|
be associated with.
|
|
|
|
A DDLElement instance can be linked to any number of schema items.
|
|
|
|
``execute_at`` builds on the ``append_ddl_listener`` interface of
|
|
:class:`.MetaData` and :class:`.Table` objects.
|
|
|
|
Caveat: Creating or dropping a Table in isolation will also trigger
|
|
any DDL set to ``execute_at`` that Table's MetaData. This may change
|
|
in a future release.
|
|
|
|
"""
|
|
|
|
def call_event(target, connection, **kw):
|
|
if self._should_execute_deprecated(event_name,
|
|
target, connection, **kw):
|
|
return connection.execute(self.against(target))
|
|
|
|
event.listen(target, "" + event_name.replace('-', '_'), call_event)
|
|
|
|
@_generative
|
|
def against(self, target):
|
|
"""Return a copy of this DDL against a specific schema item."""
|
|
|
|
self.target = target
|
|
|
|
@_generative
|
|
def execute_if(self, dialect=None, callable_=None, state=None):
|
|
"""Return a callable that will execute this
|
|
DDLElement conditionally.
|
|
|
|
Used to provide a wrapper for event listening::
|
|
|
|
event.listen(
|
|
metadata,
|
|
'before_create',
|
|
DDL("my_ddl").execute_if(dialect='postgresql')
|
|
)
|
|
|
|
:param dialect: May be a string, tuple or a callable
|
|
predicate. If a string, it will be compared to the name of the
|
|
executing database dialect::
|
|
|
|
DDL('something').execute_if(dialect='postgresql')
|
|
|
|
If a tuple, specifies multiple dialect names::
|
|
|
|
DDL('something').execute_if(dialect=('postgresql', 'mysql'))
|
|
|
|
:param callable_: A callable, which will be invoked with
|
|
four positional arguments as well as optional keyword
|
|
arguments:
|
|
|
|
:ddl:
|
|
This DDL element.
|
|
|
|
:target:
|
|
The :class:`.Table` or :class:`.MetaData` object which is the
|
|
target of this event. May be None if the DDL is executed
|
|
explicitly.
|
|
|
|
:bind:
|
|
The :class:`.Connection` being used for DDL execution
|
|
|
|
:tables:
|
|
Optional keyword argument - a list of Table objects which are to
|
|
be created/ dropped within a MetaData.create_all() or drop_all()
|
|
method call.
|
|
|
|
:state:
|
|
Optional keyword argument - will be the ``state`` argument
|
|
passed to this function.
|
|
|
|
:checkfirst:
|
|
Keyword argument, will be True if the 'checkfirst' flag was
|
|
set during the call to ``create()``, ``create_all()``,
|
|
``drop()``, ``drop_all()``.
|
|
|
|
If the callable returns a true value, the DDL statement will be
|
|
executed.
|
|
|
|
:param state: any value which will be passed to the callable\_
|
|
as the ``state`` keyword argument.
|
|
|
|
.. seealso::
|
|
|
|
:class:`.DDLEvents`
|
|
|
|
:ref:`event_toplevel`
|
|
|
|
"""
|
|
self.dialect = dialect
|
|
self.callable_ = callable_
|
|
self.state = state
|
|
|
|
def _should_execute(self, target, bind, **kw):
|
|
if self.on is not None and \
|
|
not self._should_execute_deprecated(None, target, bind, **kw):
|
|
return False
|
|
|
|
if isinstance(self.dialect, util.string_types):
|
|
if self.dialect != bind.engine.name:
|
|
return False
|
|
elif isinstance(self.dialect, (tuple, list, set)):
|
|
if bind.engine.name not in self.dialect:
|
|
return False
|
|
if self.callable_ is not None and \
|
|
not self.callable_(self, target, bind, state=self.state, **kw):
|
|
return False
|
|
|
|
return True
|
|
|
|
def _should_execute_deprecated(self, event, target, bind, **kw):
|
|
if self.on is None:
|
|
return True
|
|
elif isinstance(self.on, util.string_types):
|
|
return self.on == bind.engine.name
|
|
elif isinstance(self.on, (tuple, list, set)):
|
|
return bind.engine.name in self.on
|
|
else:
|
|
return self.on(self, event, target, bind, **kw)
|
|
|
|
def __call__(self, target, bind, **kw):
|
|
"""Execute the DDL as a ddl_listener."""
|
|
|
|
if self._should_execute(target, bind, **kw):
|
|
return bind.execute(self.against(target))
|
|
|
|
def _check_ddl_on(self, on):
|
|
if (on is not None and
|
|
(not isinstance(on, util.string_types + (tuple, list, set)) and
|
|
not util.callable(on))):
|
|
raise exc.ArgumentError(
|
|
"Expected the name of a database dialect, a tuple "
|
|
"of names, or a callable for "
|
|
"'on' criteria, got type '%s'." % type(on).__name__)
|
|
|
|
def bind(self):
|
|
if self._bind:
|
|
return self._bind
|
|
|
|
def _set_bind(self, bind):
|
|
self._bind = bind
|
|
bind = property(bind, _set_bind)
|
|
|
|
def _generate(self):
|
|
s = self.__class__.__new__(self.__class__)
|
|
s.__dict__ = self.__dict__.copy()
|
|
return s
|
|
|
|
|
|
class DDL(DDLElement):
|
|
"""A literal DDL statement.
|
|
|
|
Specifies literal SQL DDL to be executed by the database. DDL objects
|
|
function as DDL event listeners, and can be subscribed to those events
|
|
listed in :class:`.DDLEvents`, using either :class:`.Table` or
|
|
:class:`.MetaData` objects as targets. Basic templating support allows
|
|
a single DDL instance to handle repetitive tasks for multiple tables.
|
|
|
|
Examples::
|
|
|
|
from sqlalchemy import event, DDL
|
|
|
|
tbl = Table('users', metadata, Column('uid', Integer))
|
|
event.listen(tbl, 'before_create', DDL('DROP TRIGGER users_trigger'))
|
|
|
|
spow = DDL('ALTER TABLE %(table)s SET secretpowers TRUE')
|
|
event.listen(tbl, 'after_create', spow.execute_if(dialect='somedb'))
|
|
|
|
drop_spow = DDL('ALTER TABLE users SET secretpowers FALSE')
|
|
connection.execute(drop_spow)
|
|
|
|
When operating on Table events, the following ``statement``
|
|
string substitions are available::
|
|
|
|
%(table)s - the Table name, with any required quoting applied
|
|
%(schema)s - the schema name, with any required quoting applied
|
|
%(fullname)s - the Table name including schema, quoted if needed
|
|
|
|
The DDL's "context", if any, will be combined with the standard
|
|
substutions noted above. Keys present in the context will override
|
|
the standard substitutions.
|
|
|
|
"""
|
|
|
|
__visit_name__ = "ddl"
|
|
|
|
def __init__(self, statement, on=None, context=None, bind=None):
|
|
"""Create a DDL statement.
|
|
|
|
:param statement:
|
|
A string or unicode string to be executed. Statements will be
|
|
processed with Python's string formatting operator. See the
|
|
``context`` argument and the ``execute_at`` method.
|
|
|
|
A literal '%' in a statement must be escaped as '%%'.
|
|
|
|
SQL bind parameters are not available in DDL statements.
|
|
|
|
:param on:
|
|
.. deprecated:: 0.7
|
|
See :meth:`.DDLElement.execute_if`.
|
|
|
|
Optional filtering criteria. May be a string, tuple or a callable
|
|
predicate. If a string, it will be compared to the name of the
|
|
executing database dialect::
|
|
|
|
DDL('something', on='postgresql')
|
|
|
|
If a tuple, specifies multiple dialect names::
|
|
|
|
DDL('something', on=('postgresql', 'mysql'))
|
|
|
|
If a callable, it will be invoked with four positional arguments
|
|
as well as optional keyword arguments:
|
|
|
|
:ddl:
|
|
This DDL element.
|
|
|
|
:event:
|
|
The name of the event that has triggered this DDL, such as
|
|
'after-create' Will be None if the DDL is executed explicitly.
|
|
|
|
:target:
|
|
The ``Table`` or ``MetaData`` object which is the target of
|
|
this event. May be None if the DDL is executed explicitly.
|
|
|
|
:connection:
|
|
The ``Connection`` being used for DDL execution
|
|
|
|
:tables:
|
|
Optional keyword argument - a list of Table objects which are to
|
|
be created/ dropped within a MetaData.create_all() or drop_all()
|
|
method call.
|
|
|
|
|
|
If the callable returns a true value, the DDL statement will be
|
|
executed.
|
|
|
|
:param context:
|
|
Optional dictionary, defaults to None. These values will be
|
|
available for use in string substitutions on the DDL statement.
|
|
|
|
:param bind:
|
|
Optional. A :class:`.Connectable`, used by
|
|
default when ``execute()`` is invoked without a bind argument.
|
|
|
|
|
|
.. seealso::
|
|
|
|
:class:`.DDLEvents`
|
|
|
|
:mod:`sqlalchemy.event`
|
|
|
|
"""
|
|
|
|
if not isinstance(statement, util.string_types):
|
|
raise exc.ArgumentError(
|
|
"Expected a string or unicode SQL statement, got '%r'" %
|
|
statement)
|
|
|
|
self.statement = statement
|
|
self.context = context or {}
|
|
|
|
self._check_ddl_on(on)
|
|
self.on = on
|
|
self._bind = bind
|
|
|
|
def __repr__(self):
|
|
return '<%s@%s; %s>' % (
|
|
type(self).__name__, id(self),
|
|
', '.join([repr(self.statement)] +
|
|
['%s=%r' % (key, getattr(self, key))
|
|
for key in ('on', 'context')
|
|
if getattr(self, key)]))
|
|
|
|
|
|
|
|
class _CreateDropBase(DDLElement):
|
|
"""Base class for DDL constucts that represent CREATE and DROP or
|
|
equivalents.
|
|
|
|
The common theme of _CreateDropBase is a single
|
|
``element`` attribute which refers to the element
|
|
to be created or dropped.
|
|
|
|
"""
|
|
|
|
def __init__(self, element, on=None, bind=None):
|
|
self.element = element
|
|
self._check_ddl_on(on)
|
|
self.on = on
|
|
self.bind = bind
|
|
|
|
def _create_rule_disable(self, compiler):
|
|
"""Allow disable of _create_rule using a callable.
|
|
|
|
Pass to _create_rule using
|
|
util.portable_instancemethod(self._create_rule_disable)
|
|
to retain serializability.
|
|
|
|
"""
|
|
return False
|
|
|
|
|
|
class CreateSchema(_CreateDropBase):
|
|
"""Represent a CREATE SCHEMA statement.
|
|
|
|
.. versionadded:: 0.7.4
|
|
|
|
The argument here is the string name of the schema.
|
|
|
|
"""
|
|
|
|
__visit_name__ = "create_schema"
|
|
|
|
def __init__(self, name, quote=None, **kw):
|
|
"""Create a new :class:`.CreateSchema` construct."""
|
|
|
|
self.quote = quote
|
|
super(CreateSchema, self).__init__(name, **kw)
|
|
|
|
|
|
class DropSchema(_CreateDropBase):
|
|
"""Represent a DROP SCHEMA statement.
|
|
|
|
The argument here is the string name of the schema.
|
|
|
|
.. versionadded:: 0.7.4
|
|
|
|
"""
|
|
|
|
__visit_name__ = "drop_schema"
|
|
|
|
def __init__(self, name, quote=None, cascade=False, **kw):
|
|
"""Create a new :class:`.DropSchema` construct."""
|
|
|
|
self.quote = quote
|
|
self.cascade = cascade
|
|
super(DropSchema, self).__init__(name, **kw)
|
|
|
|
|
|
class CreateTable(_CreateDropBase):
|
|
"""Represent a CREATE TABLE statement."""
|
|
|
|
__visit_name__ = "create_table"
|
|
|
|
def __init__(self, element, on=None, bind=None):
|
|
"""Create a :class:`.CreateTable` construct.
|
|
|
|
:param element: a :class:`.Table` that's the subject
|
|
of the CREATE
|
|
:param on: See the description for 'on' in :class:`.DDL`.
|
|
:param bind: See the description for 'bind' in :class:`.DDL`.
|
|
|
|
"""
|
|
super(CreateTable, self).__init__(element, on=on, bind=bind)
|
|
self.columns = [CreateColumn(column)
|
|
for column in element.columns
|
|
]
|
|
|
|
|
|
class _DropView(_CreateDropBase):
|
|
"""Semi-public 'DROP VIEW' construct.
|
|
|
|
Used by the test suite for dialect-agnostic drops of views.
|
|
This object will eventually be part of a public "view" API.
|
|
|
|
"""
|
|
__visit_name__ = "drop_view"
|
|
|
|
|
|
class CreateColumn(_DDLCompiles):
|
|
"""Represent a :class:`.Column` as rendered in a CREATE TABLE statement,
|
|
via the :class:`.CreateTable` construct.
|
|
|
|
This is provided to support custom column DDL within the generation
|
|
of CREATE TABLE statements, by using the
|
|
compiler extension documented in :ref:`sqlalchemy.ext.compiler_toplevel`
|
|
to extend :class:`.CreateColumn`.
|
|
|
|
Typical integration is to examine the incoming :class:`.Column`
|
|
object, and to redirect compilation if a particular flag or condition
|
|
is found::
|
|
|
|
from sqlalchemy import schema
|
|
from sqlalchemy.ext.compiler import compiles
|
|
|
|
@compiles(schema.CreateColumn)
|
|
def compile(element, compiler, **kw):
|
|
column = element.element
|
|
|
|
if "special" not in column.info:
|
|
return compiler.visit_create_column(element, **kw)
|
|
|
|
text = "%s SPECIAL DIRECTIVE %s" % (
|
|
column.name,
|
|
compiler.type_compiler.process(column.type)
|
|
)
|
|
default = compiler.get_column_default_string(column)
|
|
if default is not None:
|
|
text += " DEFAULT " + default
|
|
|
|
if not column.nullable:
|
|
text += " NOT NULL"
|
|
|
|
if column.constraints:
|
|
text += " ".join(
|
|
compiler.process(const)
|
|
for const in column.constraints)
|
|
return text
|
|
|
|
The above construct can be applied to a :class:`.Table` as follows::
|
|
|
|
from sqlalchemy import Table, Metadata, Column, Integer, String
|
|
from sqlalchemy import schema
|
|
|
|
metadata = MetaData()
|
|
|
|
table = Table('mytable', MetaData(),
|
|
Column('x', Integer, info={"special":True}, primary_key=True),
|
|
Column('y', String(50)),
|
|
Column('z', String(20), info={"special":True})
|
|
)
|
|
|
|
metadata.create_all(conn)
|
|
|
|
Above, the directives we've added to the :attr:`.Column.info` collection
|
|
will be detected by our custom compilation scheme::
|
|
|
|
CREATE TABLE mytable (
|
|
x SPECIAL DIRECTIVE INTEGER NOT NULL,
|
|
y VARCHAR(50),
|
|
z SPECIAL DIRECTIVE VARCHAR(20),
|
|
PRIMARY KEY (x)
|
|
)
|
|
|
|
The :class:`.CreateColumn` construct can also be used to skip certain
|
|
columns when producing a ``CREATE TABLE``. This is accomplished by
|
|
creating a compilation rule that conditionally returns ``None``.
|
|
This is essentially how to produce the same effect as using the
|
|
``system=True`` argument on :class:`.Column`, which marks a column
|
|
as an implicitly-present "system" column.
|
|
|
|
For example, suppose we wish to produce a :class:`.Table` which skips
|
|
rendering of the Postgresql ``xmin`` column against the Postgresql backend,
|
|
but on other backends does render it, in anticipation of a triggered rule.
|
|
A conditional compilation rule could skip this name only on Postgresql::
|
|
|
|
from sqlalchemy.schema import CreateColumn
|
|
|
|
@compiles(CreateColumn, "postgresql")
|
|
def skip_xmin(element, compiler, **kw):
|
|
if element.element.name == 'xmin':
|
|
return None
|
|
else:
|
|
return compiler.visit_create_column(element, **kw)
|
|
|
|
|
|
my_table = Table('mytable', metadata,
|
|
Column('id', Integer, primary_key=True),
|
|
Column('xmin', Integer)
|
|
)
|
|
|
|
Above, a :class:`.CreateTable` construct will generate a ``CREATE TABLE``
|
|
which only includes the ``id`` column in the string; the ``xmin`` column
|
|
will be omitted, but only against the Postgresql backend.
|
|
|
|
.. versionadded:: 0.8.3 The :class:`.CreateColumn` construct supports
|
|
skipping of columns by returning ``None`` from a custom compilation rule.
|
|
|
|
.. versionadded:: 0.8 The :class:`.CreateColumn` construct was added
|
|
to support custom column creation styles.
|
|
|
|
"""
|
|
__visit_name__ = 'create_column'
|
|
|
|
def __init__(self, element):
|
|
self.element = element
|
|
|
|
|
|
class DropTable(_CreateDropBase):
|
|
"""Represent a DROP TABLE statement."""
|
|
|
|
__visit_name__ = "drop_table"
|
|
|
|
|
|
class CreateSequence(_CreateDropBase):
|
|
"""Represent a CREATE SEQUENCE statement."""
|
|
|
|
__visit_name__ = "create_sequence"
|
|
|
|
|
|
class DropSequence(_CreateDropBase):
|
|
"""Represent a DROP SEQUENCE statement."""
|
|
|
|
__visit_name__ = "drop_sequence"
|
|
|
|
|
|
class CreateIndex(_CreateDropBase):
|
|
"""Represent a CREATE INDEX statement."""
|
|
|
|
__visit_name__ = "create_index"
|
|
|
|
|
|
class DropIndex(_CreateDropBase):
|
|
"""Represent a DROP INDEX statement."""
|
|
|
|
__visit_name__ = "drop_index"
|
|
|
|
|
|
class AddConstraint(_CreateDropBase):
|
|
"""Represent an ALTER TABLE ADD CONSTRAINT statement."""
|
|
|
|
__visit_name__ = "add_constraint"
|
|
|
|
def __init__(self, element, *args, **kw):
|
|
super(AddConstraint, self).__init__(element, *args, **kw)
|
|
element._create_rule = util.portable_instancemethod(
|
|
self._create_rule_disable)
|
|
|
|
|
|
class DropConstraint(_CreateDropBase):
|
|
"""Represent an ALTER TABLE DROP CONSTRAINT statement."""
|
|
|
|
__visit_name__ = "drop_constraint"
|
|
|
|
def __init__(self, element, cascade=False, **kw):
|
|
self.cascade = cascade
|
|
super(DropConstraint, self).__init__(element, **kw)
|
|
element._create_rule = util.portable_instancemethod(
|
|
self._create_rule_disable)
|
|
|
|
|
|
class DDLBase(SchemaVisitor):
|
|
def __init__(self, connection):
|
|
self.connection = connection
|
|
|
|
|
|
class SchemaGenerator(DDLBase):
|
|
|
|
def __init__(self, dialect, connection, checkfirst=False,
|
|
tables=None, **kwargs):
|
|
super(SchemaGenerator, self).__init__(connection, **kwargs)
|
|
self.checkfirst = checkfirst
|
|
self.tables = tables
|
|
self.preparer = dialect.identifier_preparer
|
|
self.dialect = dialect
|
|
self.memo = {}
|
|
|
|
def _can_create_table(self, table):
|
|
self.dialect.validate_identifier(table.name)
|
|
if table.schema:
|
|
self.dialect.validate_identifier(table.schema)
|
|
return not self.checkfirst or \
|
|
not self.dialect.has_table(self.connection,
|
|
table.name, schema=table.schema)
|
|
|
|
def _can_create_sequence(self, sequence):
|
|
return self.dialect.supports_sequences and \
|
|
(
|
|
(not self.dialect.sequences_optional or
|
|
not sequence.optional) and
|
|
(
|
|
not self.checkfirst or
|
|
not self.dialect.has_sequence(
|
|
self.connection,
|
|
sequence.name,
|
|
schema=sequence.schema)
|
|
)
|
|
)
|
|
|
|
def visit_metadata(self, metadata):
|
|
if self.tables is not None:
|
|
tables = self.tables
|
|
else:
|
|
tables = list(metadata.tables.values())
|
|
collection = [t for t in sort_tables(tables)
|
|
if self._can_create_table(t)]
|
|
seq_coll = [s for s in metadata._sequences.values()
|
|
if s.column is None and self._can_create_sequence(s)]
|
|
|
|
metadata.dispatch.before_create(metadata, self.connection,
|
|
tables=collection,
|
|
checkfirst=self.checkfirst,
|
|
_ddl_runner=self)
|
|
|
|
for seq in seq_coll:
|
|
self.traverse_single(seq, create_ok=True)
|
|
|
|
for table in collection:
|
|
self.traverse_single(table, create_ok=True)
|
|
|
|
metadata.dispatch.after_create(metadata, self.connection,
|
|
tables=collection,
|
|
checkfirst=self.checkfirst,
|
|
_ddl_runner=self)
|
|
|
|
def visit_table(self, table, create_ok=False):
|
|
if not create_ok and not self._can_create_table(table):
|
|
return
|
|
|
|
table.dispatch.before_create(table, self.connection,
|
|
checkfirst=self.checkfirst,
|
|
_ddl_runner=self)
|
|
|
|
for column in table.columns:
|
|
if column.default is not None:
|
|
self.traverse_single(column.default)
|
|
|
|
self.connection.execute(CreateTable(table))
|
|
|
|
if hasattr(table, 'indexes'):
|
|
for index in table.indexes:
|
|
self.traverse_single(index)
|
|
|
|
table.dispatch.after_create(table, self.connection,
|
|
checkfirst=self.checkfirst,
|
|
_ddl_runner=self)
|
|
|
|
def visit_sequence(self, sequence, create_ok=False):
|
|
if not create_ok and not self._can_create_sequence(sequence):
|
|
return
|
|
self.connection.execute(CreateSequence(sequence))
|
|
|
|
def visit_index(self, index):
|
|
self.connection.execute(CreateIndex(index))
|
|
|
|
|
|
class SchemaDropper(DDLBase):
|
|
|
|
def __init__(self, dialect, connection, checkfirst=False,
|
|
tables=None, **kwargs):
|
|
super(SchemaDropper, self).__init__(connection, **kwargs)
|
|
self.checkfirst = checkfirst
|
|
self.tables = tables
|
|
self.preparer = dialect.identifier_preparer
|
|
self.dialect = dialect
|
|
self.memo = {}
|
|
|
|
def visit_metadata(self, metadata):
|
|
if self.tables is not None:
|
|
tables = self.tables
|
|
else:
|
|
tables = list(metadata.tables.values())
|
|
|
|
collection = [
|
|
t
|
|
for t in reversed(sort_tables(tables))
|
|
if self._can_drop_table(t)
|
|
]
|
|
|
|
seq_coll = [
|
|
s
|
|
for s in metadata._sequences.values()
|
|
if s.column is None and self._can_drop_sequence(s)
|
|
]
|
|
|
|
metadata.dispatch.before_drop(
|
|
metadata, self.connection, tables=collection,
|
|
checkfirst=self.checkfirst, _ddl_runner=self)
|
|
|
|
for table in collection:
|
|
self.traverse_single(table, drop_ok=True)
|
|
|
|
for seq in seq_coll:
|
|
self.traverse_single(seq, drop_ok=True)
|
|
|
|
metadata.dispatch.after_drop(
|
|
metadata, self.connection, tables=collection,
|
|
checkfirst=self.checkfirst, _ddl_runner=self)
|
|
|
|
def _can_drop_table(self, table):
|
|
self.dialect.validate_identifier(table.name)
|
|
if table.schema:
|
|
self.dialect.validate_identifier(table.schema)
|
|
return not self.checkfirst or self.dialect.has_table(self.connection,
|
|
table.name, schema=table.schema)
|
|
|
|
def _can_drop_sequence(self, sequence):
|
|
return self.dialect.supports_sequences and \
|
|
((not self.dialect.sequences_optional or
|
|
not sequence.optional) and
|
|
(not self.checkfirst or
|
|
self.dialect.has_sequence(
|
|
self.connection,
|
|
sequence.name,
|
|
schema=sequence.schema))
|
|
)
|
|
|
|
def visit_index(self, index):
|
|
self.connection.execute(DropIndex(index))
|
|
|
|
def visit_table(self, table, drop_ok=False):
|
|
if not drop_ok and not self._can_drop_table(table):
|
|
return
|
|
|
|
table.dispatch.before_drop(table, self.connection,
|
|
checkfirst=self.checkfirst,
|
|
_ddl_runner=self)
|
|
|
|
for column in table.columns:
|
|
if column.default is not None:
|
|
self.traverse_single(column.default)
|
|
|
|
self.connection.execute(DropTable(table))
|
|
|
|
table.dispatch.after_drop(table, self.connection,
|
|
checkfirst=self.checkfirst,
|
|
_ddl_runner=self)
|
|
|
|
def visit_sequence(self, sequence, drop_ok=False):
|
|
if not drop_ok and not self._can_drop_sequence(sequence):
|
|
return
|
|
self.connection.execute(DropSequence(sequence))
|
|
|
|
def sort_tables(tables, skip_fn=None, extra_dependencies=None):
|
|
"""sort a collection of Table objects in order of
|
|
their foreign-key dependency."""
|
|
|
|
tables = list(tables)
|
|
tuples = []
|
|
if extra_dependencies is not None:
|
|
tuples.extend(extra_dependencies)
|
|
|
|
def visit_foreign_key(fkey):
|
|
if fkey.use_alter:
|
|
return
|
|
elif skip_fn and skip_fn(fkey):
|
|
return
|
|
parent_table = fkey.column.table
|
|
if parent_table in tables:
|
|
child_table = fkey.parent.table
|
|
if parent_table is not child_table:
|
|
tuples.append((parent_table, child_table))
|
|
|
|
for table in tables:
|
|
traverse(table,
|
|
{'schema_visitor': True},
|
|
{'foreign_key': visit_foreign_key})
|
|
|
|
tuples.extend(
|
|
[parent, table] for parent in table._extra_dependencies
|
|
)
|
|
|
|
return list(topological.sort(tuples, tables))
|
|
|