def rename(self, name, connection=None, **kwargs):
"""Change the name of an index.
:param name: New name of the Index.
:type name: string
:param connection: reuse connection istead of creating new one.
:type connection: :class:`sqlalchemy.engine.base.Connection` instance
"""
engine = self.table.bind
self.new_name = name
visitorcallable = get_engine_visitor(engine, 'schemachanger')
engine._run_visitor(visitorcallable, self, connection, **kwargs)
self.name = name
def alter_column(*p, **k):
"""Alter a column.
This is a helper function that creates a :class:`ColumnDelta` and
runs it.
:argument column:
The name of the column to be altered or a
:class:`ChangesetColumn` column representing it.
:param table:
A :class:`~sqlalchemy.schema.Table` or table name to
for the table where the column will be changed.
:param engine:
The :class:`~sqlalchemy.engine.base.Engine` to use for table
reflection and schema alterations.
:returns: A :class:`ColumnDelta` instance representing the change.
"""
if 'table' not in k and isinstance(p[0], sqlalchemy.Column):
k['table'] = p[0].table
if 'engine' not in k:
k['engine'] = k['table'].bind
# deprecation
if len(p) >= 2 and isinstance(p[1], sqlalchemy.Column):
warnings.warn(
"Passing a Column object to alter_column is deprecated."
" Just pass in keyword parameters instead.",
MigrateDeprecationWarning
)
engine = k['engine']
# enough tests seem to break when metadata is always altered
# that this crutch has to be left in until they can be sorted
# out
k['alter_metadata']=True
delta = ColumnDelta(*p, **k)
visitorcallable = get_engine_visitor(engine, 'schemachanger')
engine._run_visitor(visitorcallable, delta)
return delta
def drop(self, table=None, connection=None, **kwargs):
"""Drop this column from the database, leaving its table intact.
``ALTER TABLE DROP COLUMN``, for most databases.
:param connection: reuse connection istead of creating new one.
:type connection: :class:`sqlalchemy.engine.base.Connection` instance
"""
if table is not None:
self.table = table
engine = self.table.bind
visitorcallable = get_engine_visitor(engine, 'columndropper')
engine._run_visitor(visitorcallable, self, connection, **kwargs)
self.remove_from_table(self.table, unset_table=False)
self.table = None
return self
def rename(self, name, connection=None, **kwargs):
"""Rename this table.
:param name: New name of the table.
:type name: string
:param connection: reuse connection istead of creating new one.
:type connection: :class:`sqlalchemy.engine.base.Connection` instance
"""
engine = self.bind
self.new_name = name
visitorcallable = get_engine_visitor(engine, 'schemachanger')
run_single_visitor(engine, visitorcallable, self, connection, **kwargs)
# Fix metadata registration
self.name = name
self.deregister()
self._set_parent(self.metadata)
def create(self, table=None, index_name=None, unique_name=None,
primary_key_name=None, populate_default=True, connection=None, **kwargs):
"""Create this column in the database.
Assumes the given table exists. ``ALTER TABLE ADD COLUMN``,
for most databases.
:param table: Table instance to create on.
:param index_name: Creates :class:`ChangesetIndex` on this column.
:param unique_name: Creates :class:\
`~migrate.changeset.constraint.UniqueConstraint` on this column.
:param primary_key_name: Creates :class:\
`~migrate.changeset.constraint.PrimaryKeyConstraint` on this column.
:param populate_default: If True, created column will be \
populated with defaults
:param connection: reuse connection istead of creating new one.
:type table: Table instance
:type index_name: string
:type unique_name: string
:type primary_key_name: string
:type populate_default: bool
:type connection: :class:`sqlalchemy.engine.base.Connection` instance
:returns: self
"""
self.populate_default = populate_default
self.index_name = index_name
self.unique_name = unique_name
self.primary_key_name = primary_key_name
for cons in ('index_name', 'unique_name', 'primary_key_name'):
self._check_sanity_constraints(cons)
self.add_to_table(table)
engine = self.table.bind
visitorcallable = get_engine_visitor(engine, 'columngenerator')
engine._run_visitor(visitorcallable, self, connection, **kwargs)
# TODO: reuse existing connection
if self.populate_default and self.default is not None:
stmt = table.update().values({self: engine._execute_default(self.default)})
engine.execute(stmt)
return self
def __do_imports(self, visitor_name, *a, **kw):
engine = kw.pop('engine', self.table.bind)
from promogest.lib.migrate.changeset.databases.visitor import (get_engine_visitor,
run_single_visitor)
visitorcallable = get_engine_visitor(engine, visitor_name)
run_single_visitor(engine, visitorcallable, self, *a, **kw)