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1185 lines
45 KiB
1185 lines
45 KiB
# ### this file stubs are generated by tools/write_pyi.py - do not edit ###
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# ### imports are manually managed
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from contextlib import contextmanager
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from typing import Any
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from typing import Callable
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from typing import Dict
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from typing import Iterator
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from typing import List
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from typing import Literal
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from typing import Mapping
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from typing import Optional
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from typing import Sequence
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from typing import Tuple
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from typing import Type
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from typing import TYPE_CHECKING
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from typing import Union
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from sqlalchemy.sql.expression import TableClause
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from sqlalchemy.sql.expression import Update
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if TYPE_CHECKING:
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from sqlalchemy.engine import Connection
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from sqlalchemy.sql.elements import BinaryExpression
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from sqlalchemy.sql.elements import conv
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from sqlalchemy.sql.elements import TextClause
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from sqlalchemy.sql.functions import Function
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from sqlalchemy.sql.schema import Column
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from sqlalchemy.sql.schema import Computed
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from sqlalchemy.sql.schema import Identity
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from sqlalchemy.sql.schema import SchemaItem
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from sqlalchemy.sql.schema import Table
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from sqlalchemy.sql.type_api import TypeEngine
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from sqlalchemy.util import immutabledict
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from .operations.ops import BatchOperations
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from .operations.ops import MigrateOperation
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from .runtime.migration import MigrationContext
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from .util.sqla_compat import _literal_bindparam
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### end imports ###
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def add_column(
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table_name: str, column: Column, schema: Optional[str] = None
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) -> Optional[Table]:
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r"""Issue an "add column" instruction using the current
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migration context.
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e.g.::
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from alembic import op
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from sqlalchemy import Column, String
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op.add_column('organization',
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Column('name', String())
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)
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The provided :class:`~sqlalchemy.schema.Column` object can also
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specify a :class:`~sqlalchemy.schema.ForeignKey`, referencing
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a remote table name. Alembic will automatically generate a stub
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"referenced" table and emit a second ALTER statement in order
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to add the constraint separately::
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from alembic import op
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from sqlalchemy import Column, INTEGER, ForeignKey
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op.add_column('organization',
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Column('account_id', INTEGER, ForeignKey('accounts.id'))
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)
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Note that this statement uses the :class:`~sqlalchemy.schema.Column`
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construct as is from the SQLAlchemy library. In particular,
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default values to be created on the database side are
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specified using the ``server_default`` parameter, and not
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``default`` which only specifies Python-side defaults::
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from alembic import op
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from sqlalchemy import Column, TIMESTAMP, func
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# specify "DEFAULT NOW" along with the column add
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op.add_column('account',
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Column('timestamp', TIMESTAMP, server_default=func.now())
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)
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:param table_name: String name of the parent table.
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:param column: a :class:`sqlalchemy.schema.Column` object
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representing the new column.
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:param schema: Optional schema name to operate within. To control
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quoting of the schema outside of the default behavior, use
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the SQLAlchemy construct
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:class:`~sqlalchemy.sql.elements.quoted_name`.
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"""
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def alter_column(
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table_name: str,
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column_name: str,
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nullable: Optional[bool] = None,
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comment: Union[str, Literal[False], None] = False,
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server_default: Any = False,
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new_column_name: Optional[str] = None,
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type_: Union[TypeEngine, Type[TypeEngine], None] = None,
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existing_type: Union[TypeEngine, Type[TypeEngine], None] = None,
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existing_server_default: Union[
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str, bool, Identity, Computed, None
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] = False,
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existing_nullable: Optional[bool] = None,
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existing_comment: Optional[str] = None,
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schema: Optional[str] = None,
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**kw: Any
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) -> Optional[Table]:
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r"""Issue an "alter column" instruction using the
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current migration context.
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Generally, only that aspect of the column which
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is being changed, i.e. name, type, nullability,
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default, needs to be specified. Multiple changes
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can also be specified at once and the backend should
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"do the right thing", emitting each change either
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separately or together as the backend allows.
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MySQL has special requirements here, since MySQL
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cannot ALTER a column without a full specification.
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When producing MySQL-compatible migration files,
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it is recommended that the ``existing_type``,
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``existing_server_default``, and ``existing_nullable``
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parameters be present, if not being altered.
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Type changes which are against the SQLAlchemy
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"schema" types :class:`~sqlalchemy.types.Boolean`
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and :class:`~sqlalchemy.types.Enum` may also
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add or drop constraints which accompany those
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types on backends that don't support them natively.
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The ``existing_type`` argument is
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used in this case to identify and remove a previous
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constraint that was bound to the type object.
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:param table_name: string name of the target table.
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:param column_name: string name of the target column,
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as it exists before the operation begins.
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:param nullable: Optional; specify ``True`` or ``False``
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to alter the column's nullability.
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:param server_default: Optional; specify a string
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SQL expression, :func:`~sqlalchemy.sql.expression.text`,
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or :class:`~sqlalchemy.schema.DefaultClause` to indicate
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an alteration to the column's default value.
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Set to ``None`` to have the default removed.
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:param comment: optional string text of a new comment to add to the
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column.
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.. versionadded:: 1.0.6
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:param new_column_name: Optional; specify a string name here to
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indicate the new name within a column rename operation.
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:param type\_: Optional; a :class:`~sqlalchemy.types.TypeEngine`
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type object to specify a change to the column's type.
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For SQLAlchemy types that also indicate a constraint (i.e.
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:class:`~sqlalchemy.types.Boolean`, :class:`~sqlalchemy.types.Enum`),
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the constraint is also generated.
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:param autoincrement: set the ``AUTO_INCREMENT`` flag of the column;
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currently understood by the MySQL dialect.
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:param existing_type: Optional; a
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:class:`~sqlalchemy.types.TypeEngine`
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type object to specify the previous type. This
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is required for all MySQL column alter operations that
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don't otherwise specify a new type, as well as for
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when nullability is being changed on a SQL Server
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column. It is also used if the type is a so-called
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SQLlchemy "schema" type which may define a constraint (i.e.
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:class:`~sqlalchemy.types.Boolean`,
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:class:`~sqlalchemy.types.Enum`),
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so that the constraint can be dropped.
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:param existing_server_default: Optional; The existing
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default value of the column. Required on MySQL if
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an existing default is not being changed; else MySQL
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removes the default.
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:param existing_nullable: Optional; the existing nullability
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of the column. Required on MySQL if the existing nullability
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is not being changed; else MySQL sets this to NULL.
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:param existing_autoincrement: Optional; the existing autoincrement
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of the column. Used for MySQL's system of altering a column
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that specifies ``AUTO_INCREMENT``.
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:param existing_comment: string text of the existing comment on the
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column to be maintained. Required on MySQL if the existing comment
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on the column is not being changed.
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.. versionadded:: 1.0.6
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:param schema: Optional schema name to operate within. To control
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quoting of the schema outside of the default behavior, use
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the SQLAlchemy construct
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:class:`~sqlalchemy.sql.elements.quoted_name`.
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:param postgresql_using: String argument which will indicate a
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SQL expression to render within the Postgresql-specific USING clause
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within ALTER COLUMN. This string is taken directly as raw SQL which
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must explicitly include any necessary quoting or escaping of tokens
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within the expression.
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"""
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@contextmanager
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def batch_alter_table(
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table_name: str,
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schema: Optional[str] = None,
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recreate: Literal["auto", "always", "never"] = "auto",
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partial_reordering: Optional[tuple] = None,
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copy_from: Optional[Table] = None,
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table_args: Tuple[Any, ...] = (),
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table_kwargs: Mapping[str, Any] = immutabledict({}),
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reflect_args: Tuple[Any, ...] = (),
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reflect_kwargs: Mapping[str, Any] = immutabledict({}),
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naming_convention: Optional[Dict[str, str]] = None,
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) -> Iterator[BatchOperations]:
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r"""Invoke a series of per-table migrations in batch.
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Batch mode allows a series of operations specific to a table
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to be syntactically grouped together, and allows for alternate
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modes of table migration, in particular the "recreate" style of
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migration required by SQLite.
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"recreate" style is as follows:
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1. A new table is created with the new specification, based on the
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migration directives within the batch, using a temporary name.
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2. the data copied from the existing table to the new table.
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3. the existing table is dropped.
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4. the new table is renamed to the existing table name.
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The directive by default will only use "recreate" style on the
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SQLite backend, and only if directives are present which require
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this form, e.g. anything other than ``add_column()``. The batch
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operation on other backends will proceed using standard ALTER TABLE
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operations.
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The method is used as a context manager, which returns an instance
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of :class:`.BatchOperations`; this object is the same as
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:class:`.Operations` except that table names and schema names
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are omitted. E.g.::
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with op.batch_alter_table("some_table") as batch_op:
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batch_op.add_column(Column('foo', Integer))
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batch_op.drop_column('bar')
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The operations within the context manager are invoked at once
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when the context is ended. When run against SQLite, if the
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migrations include operations not supported by SQLite's ALTER TABLE,
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the entire table will be copied to a new one with the new
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specification, moving all data across as well.
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The copy operation by default uses reflection to retrieve the current
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structure of the table, and therefore :meth:`.batch_alter_table`
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in this mode requires that the migration is run in "online" mode.
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The ``copy_from`` parameter may be passed which refers to an existing
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:class:`.Table` object, which will bypass this reflection step.
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.. note:: The table copy operation will currently not copy
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CHECK constraints, and may not copy UNIQUE constraints that are
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unnamed, as is possible on SQLite. See the section
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|
:ref:`sqlite_batch_constraints` for workarounds.
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|
:param table_name: name of table
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|
:param schema: optional schema name.
|
|
:param recreate: under what circumstances the table should be
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recreated. At its default of ``"auto"``, the SQLite dialect will
|
|
recreate the table if any operations other than ``add_column()``,
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|
``create_index()``, or ``drop_index()`` are
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|
present. Other options include ``"always"`` and ``"never"``.
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:param copy_from: optional :class:`~sqlalchemy.schema.Table` object
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|
that will act as the structure of the table being copied. If omitted,
|
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table reflection is used to retrieve the structure of the table.
|
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|
|
.. seealso::
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|
|
|
:ref:`batch_offline_mode`
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|
:paramref:`~.Operations.batch_alter_table.reflect_args`
|
|
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|
:paramref:`~.Operations.batch_alter_table.reflect_kwargs`
|
|
|
|
:param reflect_args: a sequence of additional positional arguments that
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|
will be applied to the table structure being reflected / copied;
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|
this may be used to pass column and constraint overrides to the
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table that will be reflected, in lieu of passing the whole
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|
:class:`~sqlalchemy.schema.Table` using
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:paramref:`~.Operations.batch_alter_table.copy_from`.
|
|
:param reflect_kwargs: a dictionary of additional keyword arguments
|
|
that will be applied to the table structure being copied; this may be
|
|
used to pass additional table and reflection options to the table that
|
|
will be reflected, in lieu of passing the whole
|
|
:class:`~sqlalchemy.schema.Table` using
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|
:paramref:`~.Operations.batch_alter_table.copy_from`.
|
|
:param table_args: a sequence of additional positional arguments that
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|
will be applied to the new :class:`~sqlalchemy.schema.Table` when
|
|
created, in addition to those copied from the source table.
|
|
This may be used to provide additional constraints such as CHECK
|
|
constraints that may not be reflected.
|
|
:param table_kwargs: a dictionary of additional keyword arguments
|
|
that will be applied to the new :class:`~sqlalchemy.schema.Table`
|
|
when created, in addition to those copied from the source table.
|
|
This may be used to provide for additional table options that may
|
|
not be reflected.
|
|
:param naming_convention: a naming convention dictionary of the form
|
|
described at :ref:`autogen_naming_conventions` which will be applied
|
|
to the :class:`~sqlalchemy.schema.MetaData` during the reflection
|
|
process. This is typically required if one wants to drop SQLite
|
|
constraints, as these constraints will not have names when
|
|
reflected on this backend. Requires SQLAlchemy **0.9.4** or greater.
|
|
|
|
.. seealso::
|
|
|
|
:ref:`dropping_sqlite_foreign_keys`
|
|
|
|
:param partial_reordering: a list of tuples, each suggesting a desired
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|
ordering of two or more columns in the newly created table. Requires
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|
that :paramref:`.batch_alter_table.recreate` is set to ``"always"``.
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|
Examples, given a table with columns "a", "b", "c", and "d":
|
|
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Specify the order of all columns::
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with op.batch_alter_table(
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"some_table", recreate="always",
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partial_reordering=[("c", "d", "a", "b")]
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) as batch_op:
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pass
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Ensure "d" appears before "c", and "b", appears before "a"::
|
|
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|
with op.batch_alter_table(
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"some_table", recreate="always",
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|
partial_reordering=[("d", "c"), ("b", "a")]
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|
) as batch_op:
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pass
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The ordering of columns not included in the partial_reordering
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|
set is undefined. Therefore it is best to specify the complete
|
|
ordering of all columns for best results.
|
|
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|
.. versionadded:: 1.4.0
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|
.. note:: batch mode requires SQLAlchemy 0.8 or above.
|
|
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|
.. seealso::
|
|
|
|
:ref:`batch_migrations`
|
|
|
|
"""
|
|
|
|
def bulk_insert(
|
|
table: Union[Table, TableClause],
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|
rows: List[dict],
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|
multiinsert: bool = True,
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|
) -> None:
|
|
r"""Issue a "bulk insert" operation using the current
|
|
migration context.
|
|
|
|
This provides a means of representing an INSERT of multiple rows
|
|
which works equally well in the context of executing on a live
|
|
connection as well as that of generating a SQL script. In the
|
|
case of a SQL script, the values are rendered inline into the
|
|
statement.
|
|
|
|
e.g.::
|
|
|
|
from alembic import op
|
|
from datetime import date
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|
from sqlalchemy.sql import table, column
|
|
from sqlalchemy import String, Integer, Date
|
|
|
|
# Create an ad-hoc table to use for the insert statement.
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|
accounts_table = table('account',
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|
column('id', Integer),
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|
column('name', String),
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|
column('create_date', Date)
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|
)
|
|
|
|
op.bulk_insert(accounts_table,
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|
[
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|
{'id':1, 'name':'John Smith',
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|
'create_date':date(2010, 10, 5)},
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|
{'id':2, 'name':'Ed Williams',
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|
'create_date':date(2007, 5, 27)},
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|
{'id':3, 'name':'Wendy Jones',
|
|
'create_date':date(2008, 8, 15)},
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|
]
|
|
)
|
|
|
|
When using --sql mode, some datatypes may not render inline
|
|
automatically, such as dates and other special types. When this
|
|
issue is present, :meth:`.Operations.inline_literal` may be used::
|
|
|
|
op.bulk_insert(accounts_table,
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|
[
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|
{'id':1, 'name':'John Smith',
|
|
'create_date':op.inline_literal("2010-10-05")},
|
|
{'id':2, 'name':'Ed Williams',
|
|
'create_date':op.inline_literal("2007-05-27")},
|
|
{'id':3, 'name':'Wendy Jones',
|
|
'create_date':op.inline_literal("2008-08-15")},
|
|
],
|
|
multiinsert=False
|
|
)
|
|
|
|
When using :meth:`.Operations.inline_literal` in conjunction with
|
|
:meth:`.Operations.bulk_insert`, in order for the statement to work
|
|
in "online" (e.g. non --sql) mode, the
|
|
:paramref:`~.Operations.bulk_insert.multiinsert`
|
|
flag should be set to ``False``, which will have the effect of
|
|
individual INSERT statements being emitted to the database, each
|
|
with a distinct VALUES clause, so that the "inline" values can
|
|
still be rendered, rather than attempting to pass the values
|
|
as bound parameters.
|
|
|
|
:param table: a table object which represents the target of the INSERT.
|
|
|
|
:param rows: a list of dictionaries indicating rows.
|
|
|
|
:param multiinsert: when at its default of True and --sql mode is not
|
|
enabled, the INSERT statement will be executed using
|
|
"executemany()" style, where all elements in the list of
|
|
dictionaries are passed as bound parameters in a single
|
|
list. Setting this to False results in individual INSERT
|
|
statements being emitted per parameter set, and is needed
|
|
in those cases where non-literal values are present in the
|
|
parameter sets.
|
|
|
|
"""
|
|
|
|
def create_check_constraint(
|
|
constraint_name: Optional[str],
|
|
table_name: str,
|
|
condition: Union[str, BinaryExpression],
|
|
schema: Optional[str] = None,
|
|
**kw: Any
|
|
) -> Optional[Table]:
|
|
r"""Issue a "create check constraint" instruction using the
|
|
current migration context.
|
|
|
|
e.g.::
|
|
|
|
from alembic import op
|
|
from sqlalchemy.sql import column, func
|
|
|
|
op.create_check_constraint(
|
|
"ck_user_name_len",
|
|
"user",
|
|
func.len(column('name')) > 5
|
|
)
|
|
|
|
CHECK constraints are usually against a SQL expression, so ad-hoc
|
|
table metadata is usually needed. The function will convert the given
|
|
arguments into a :class:`sqlalchemy.schema.CheckConstraint` bound
|
|
to an anonymous table in order to emit the CREATE statement.
|
|
|
|
:param name: Name of the check constraint. The name is necessary
|
|
so that an ALTER statement can be emitted. For setups that
|
|
use an automated naming scheme such as that described at
|
|
:ref:`sqla:constraint_naming_conventions`,
|
|
``name`` here can be ``None``, as the event listener will
|
|
apply the name to the constraint object when it is associated
|
|
with the table.
|
|
:param table_name: String name of the source table.
|
|
:param condition: SQL expression that's the condition of the
|
|
constraint. Can be a string or SQLAlchemy expression language
|
|
structure.
|
|
:param deferrable: optional bool. If set, emit DEFERRABLE or
|
|
NOT DEFERRABLE when issuing DDL for this constraint.
|
|
:param initially: optional string. If set, emit INITIALLY <value>
|
|
when issuing DDL for this constraint.
|
|
:param schema: Optional schema name to operate within. To control
|
|
quoting of the schema outside of the default behavior, use
|
|
the SQLAlchemy construct
|
|
:class:`~sqlalchemy.sql.elements.quoted_name`.
|
|
|
|
"""
|
|
|
|
def create_exclude_constraint(
|
|
constraint_name: str, table_name: str, *elements: Any, **kw: Any
|
|
) -> Optional[Table]:
|
|
r"""Issue an alter to create an EXCLUDE constraint using the
|
|
current migration context.
|
|
|
|
.. note:: This method is Postgresql specific, and additionally
|
|
requires at least SQLAlchemy 1.0.
|
|
|
|
e.g.::
|
|
|
|
from alembic import op
|
|
|
|
op.create_exclude_constraint(
|
|
"user_excl",
|
|
"user",
|
|
|
|
("period", '&&'),
|
|
("group", '='),
|
|
where=("group != 'some group'")
|
|
|
|
)
|
|
|
|
Note that the expressions work the same way as that of
|
|
the ``ExcludeConstraint`` object itself; if plain strings are
|
|
passed, quoting rules must be applied manually.
|
|
|
|
:param name: Name of the constraint.
|
|
:param table_name: String name of the source table.
|
|
:param elements: exclude conditions.
|
|
:param where: SQL expression or SQL string with optional WHERE
|
|
clause.
|
|
:param deferrable: optional bool. If set, emit DEFERRABLE or
|
|
NOT DEFERRABLE when issuing DDL for this constraint.
|
|
:param initially: optional string. If set, emit INITIALLY <value>
|
|
when issuing DDL for this constraint.
|
|
:param schema: Optional schema name to operate within.
|
|
|
|
"""
|
|
|
|
def create_foreign_key(
|
|
constraint_name: Optional[str],
|
|
source_table: str,
|
|
referent_table: str,
|
|
local_cols: List[str],
|
|
remote_cols: List[str],
|
|
onupdate: Optional[str] = None,
|
|
ondelete: Optional[str] = None,
|
|
deferrable: Optional[bool] = None,
|
|
initially: Optional[str] = None,
|
|
match: Optional[str] = None,
|
|
source_schema: Optional[str] = None,
|
|
referent_schema: Optional[str] = None,
|
|
**dialect_kw: Any
|
|
) -> Optional[Table]:
|
|
r"""Issue a "create foreign key" instruction using the
|
|
current migration context.
|
|
|
|
e.g.::
|
|
|
|
from alembic import op
|
|
op.create_foreign_key(
|
|
"fk_user_address", "address",
|
|
"user", ["user_id"], ["id"])
|
|
|
|
This internally generates a :class:`~sqlalchemy.schema.Table` object
|
|
containing the necessary columns, then generates a new
|
|
:class:`~sqlalchemy.schema.ForeignKeyConstraint`
|
|
object which it then associates with the
|
|
:class:`~sqlalchemy.schema.Table`.
|
|
Any event listeners associated with this action will be fired
|
|
off normally. The :class:`~sqlalchemy.schema.AddConstraint`
|
|
construct is ultimately used to generate the ALTER statement.
|
|
|
|
:param constraint_name: Name of the foreign key constraint. The name
|
|
is necessary so that an ALTER statement can be emitted. For setups
|
|
that use an automated naming scheme such as that described at
|
|
:ref:`sqla:constraint_naming_conventions`,
|
|
``name`` here can be ``None``, as the event listener will
|
|
apply the name to the constraint object when it is associated
|
|
with the table.
|
|
:param source_table: String name of the source table.
|
|
:param referent_table: String name of the destination table.
|
|
:param local_cols: a list of string column names in the
|
|
source table.
|
|
:param remote_cols: a list of string column names in the
|
|
remote table.
|
|
:param onupdate: Optional string. If set, emit ON UPDATE <value> when
|
|
issuing DDL for this constraint. Typical values include CASCADE,
|
|
DELETE and RESTRICT.
|
|
:param ondelete: Optional string. If set, emit ON DELETE <value> when
|
|
issuing DDL for this constraint. Typical values include CASCADE,
|
|
DELETE and RESTRICT.
|
|
:param deferrable: optional bool. If set, emit DEFERRABLE or NOT
|
|
DEFERRABLE when issuing DDL for this constraint.
|
|
:param source_schema: Optional schema name of the source table.
|
|
:param referent_schema: Optional schema name of the destination table.
|
|
|
|
"""
|
|
|
|
def create_index(
|
|
index_name: Optional[str],
|
|
table_name: str,
|
|
columns: Sequence[Union[str, TextClause, Function[Any]]],
|
|
schema: Optional[str] = None,
|
|
unique: bool = False,
|
|
**kw: Any
|
|
) -> Optional[Table]:
|
|
r"""Issue a "create index" instruction using the current
|
|
migration context.
|
|
|
|
e.g.::
|
|
|
|
from alembic import op
|
|
op.create_index('ik_test', 't1', ['foo', 'bar'])
|
|
|
|
Functional indexes can be produced by using the
|
|
:func:`sqlalchemy.sql.expression.text` construct::
|
|
|
|
from alembic import op
|
|
from sqlalchemy import text
|
|
op.create_index('ik_test', 't1', [text('lower(foo)')])
|
|
|
|
:param index_name: name of the index.
|
|
:param table_name: name of the owning table.
|
|
:param columns: a list consisting of string column names and/or
|
|
:func:`~sqlalchemy.sql.expression.text` constructs.
|
|
:param schema: Optional schema name to operate within. To control
|
|
quoting of the schema outside of the default behavior, use
|
|
the SQLAlchemy construct
|
|
:class:`~sqlalchemy.sql.elements.quoted_name`.
|
|
:param unique: If True, create a unique index.
|
|
|
|
:param quote:
|
|
Force quoting of this column's name on or off, corresponding
|
|
to ``True`` or ``False``. When left at its default
|
|
of ``None``, the column identifier will be quoted according to
|
|
whether the name is case sensitive (identifiers with at least one
|
|
upper case character are treated as case sensitive), or if it's a
|
|
reserved word. This flag is only needed to force quoting of a
|
|
reserved word which is not known by the SQLAlchemy dialect.
|
|
|
|
:param \**kw: Additional keyword arguments not mentioned above are
|
|
dialect specific, and passed in the form
|
|
``<dialectname>_<argname>``.
|
|
See the documentation regarding an individual dialect at
|
|
:ref:`dialect_toplevel` for detail on documented arguments.
|
|
|
|
"""
|
|
|
|
def create_primary_key(
|
|
constraint_name: Optional[str],
|
|
table_name: str,
|
|
columns: List[str],
|
|
schema: Optional[str] = None,
|
|
) -> Optional[Table]:
|
|
r"""Issue a "create primary key" instruction using the current
|
|
migration context.
|
|
|
|
e.g.::
|
|
|
|
from alembic import op
|
|
op.create_primary_key(
|
|
"pk_my_table", "my_table",
|
|
["id", "version"]
|
|
)
|
|
|
|
This internally generates a :class:`~sqlalchemy.schema.Table` object
|
|
containing the necessary columns, then generates a new
|
|
:class:`~sqlalchemy.schema.PrimaryKeyConstraint`
|
|
object which it then associates with the
|
|
:class:`~sqlalchemy.schema.Table`.
|
|
Any event listeners associated with this action will be fired
|
|
off normally. The :class:`~sqlalchemy.schema.AddConstraint`
|
|
construct is ultimately used to generate the ALTER statement.
|
|
|
|
:param constraint_name: Name of the primary key constraint. The name
|
|
is necessary so that an ALTER statement can be emitted. For setups
|
|
that use an automated naming scheme such as that described at
|
|
:ref:`sqla:constraint_naming_conventions`
|
|
``name`` here can be ``None``, as the event listener will
|
|
apply the name to the constraint object when it is associated
|
|
with the table.
|
|
:param table_name: String name of the target table.
|
|
:param columns: a list of string column names to be applied to the
|
|
primary key constraint.
|
|
:param schema: Optional schema name to operate within. To control
|
|
quoting of the schema outside of the default behavior, use
|
|
the SQLAlchemy construct
|
|
:class:`~sqlalchemy.sql.elements.quoted_name`.
|
|
|
|
"""
|
|
|
|
def create_table(
|
|
table_name: str, *columns: SchemaItem, **kw: Any
|
|
) -> Optional[Table]:
|
|
r"""Issue a "create table" instruction using the current migration
|
|
context.
|
|
|
|
This directive receives an argument list similar to that of the
|
|
traditional :class:`sqlalchemy.schema.Table` construct, but without the
|
|
metadata::
|
|
|
|
from sqlalchemy import INTEGER, VARCHAR, NVARCHAR, Column
|
|
from alembic import op
|
|
|
|
op.create_table(
|
|
'account',
|
|
Column('id', INTEGER, primary_key=True),
|
|
Column('name', VARCHAR(50), nullable=False),
|
|
Column('description', NVARCHAR(200)),
|
|
Column('timestamp', TIMESTAMP, server_default=func.now())
|
|
)
|
|
|
|
Note that :meth:`.create_table` accepts
|
|
:class:`~sqlalchemy.schema.Column`
|
|
constructs directly from the SQLAlchemy library. In particular,
|
|
default values to be created on the database side are
|
|
specified using the ``server_default`` parameter, and not
|
|
``default`` which only specifies Python-side defaults::
|
|
|
|
from alembic import op
|
|
from sqlalchemy import Column, TIMESTAMP, func
|
|
|
|
# specify "DEFAULT NOW" along with the "timestamp" column
|
|
op.create_table('account',
|
|
Column('id', INTEGER, primary_key=True),
|
|
Column('timestamp', TIMESTAMP, server_default=func.now())
|
|
)
|
|
|
|
The function also returns a newly created
|
|
:class:`~sqlalchemy.schema.Table` object, corresponding to the table
|
|
specification given, which is suitable for
|
|
immediate SQL operations, in particular
|
|
:meth:`.Operations.bulk_insert`::
|
|
|
|
from sqlalchemy import INTEGER, VARCHAR, NVARCHAR, Column
|
|
from alembic import op
|
|
|
|
account_table = op.create_table(
|
|
'account',
|
|
Column('id', INTEGER, primary_key=True),
|
|
Column('name', VARCHAR(50), nullable=False),
|
|
Column('description', NVARCHAR(200)),
|
|
Column('timestamp', TIMESTAMP, server_default=func.now())
|
|
)
|
|
|
|
op.bulk_insert(
|
|
account_table,
|
|
[
|
|
{"name": "A1", "description": "account 1"},
|
|
{"name": "A2", "description": "account 2"},
|
|
]
|
|
)
|
|
|
|
:param table_name: Name of the table
|
|
:param \*columns: collection of :class:`~sqlalchemy.schema.Column`
|
|
objects within
|
|
the table, as well as optional :class:`~sqlalchemy.schema.Constraint`
|
|
objects
|
|
and :class:`~.sqlalchemy.schema.Index` objects.
|
|
:param schema: Optional schema name to operate within. To control
|
|
quoting of the schema outside of the default behavior, use
|
|
the SQLAlchemy construct
|
|
:class:`~sqlalchemy.sql.elements.quoted_name`.
|
|
:param \**kw: Other keyword arguments are passed to the underlying
|
|
:class:`sqlalchemy.schema.Table` object created for the command.
|
|
|
|
:return: the :class:`~sqlalchemy.schema.Table` object corresponding
|
|
to the parameters given.
|
|
|
|
"""
|
|
|
|
def create_table_comment(
|
|
table_name: str,
|
|
comment: Optional[str],
|
|
existing_comment: None = None,
|
|
schema: Optional[str] = None,
|
|
) -> Optional[Table]:
|
|
r"""Emit a COMMENT ON operation to set the comment for a table.
|
|
|
|
.. versionadded:: 1.0.6
|
|
|
|
:param table_name: string name of the target table.
|
|
:param comment: string value of the comment being registered against
|
|
the specified table.
|
|
:param existing_comment: String value of a comment
|
|
already registered on the specified table, used within autogenerate
|
|
so that the operation is reversible, but not required for direct
|
|
use.
|
|
|
|
.. seealso::
|
|
|
|
:meth:`.Operations.drop_table_comment`
|
|
|
|
:paramref:`.Operations.alter_column.comment`
|
|
|
|
"""
|
|
|
|
def create_unique_constraint(
|
|
constraint_name: Optional[str],
|
|
table_name: str,
|
|
columns: Sequence[str],
|
|
schema: Optional[str] = None,
|
|
**kw: Any
|
|
) -> Any:
|
|
r"""Issue a "create unique constraint" instruction using the
|
|
current migration context.
|
|
|
|
e.g.::
|
|
|
|
from alembic import op
|
|
op.create_unique_constraint("uq_user_name", "user", ["name"])
|
|
|
|
This internally generates a :class:`~sqlalchemy.schema.Table` object
|
|
containing the necessary columns, then generates a new
|
|
:class:`~sqlalchemy.schema.UniqueConstraint`
|
|
object which it then associates with the
|
|
:class:`~sqlalchemy.schema.Table`.
|
|
Any event listeners associated with this action will be fired
|
|
off normally. The :class:`~sqlalchemy.schema.AddConstraint`
|
|
construct is ultimately used to generate the ALTER statement.
|
|
|
|
:param name: Name of the unique constraint. The name is necessary
|
|
so that an ALTER statement can be emitted. For setups that
|
|
use an automated naming scheme such as that described at
|
|
:ref:`sqla:constraint_naming_conventions`,
|
|
``name`` here can be ``None``, as the event listener will
|
|
apply the name to the constraint object when it is associated
|
|
with the table.
|
|
:param table_name: String name of the source table.
|
|
:param columns: a list of string column names in the
|
|
source table.
|
|
:param deferrable: optional bool. If set, emit DEFERRABLE or
|
|
NOT DEFERRABLE when issuing DDL for this constraint.
|
|
:param initially: optional string. If set, emit INITIALLY <value>
|
|
when issuing DDL for this constraint.
|
|
:param schema: Optional schema name to operate within. To control
|
|
quoting of the schema outside of the default behavior, use
|
|
the SQLAlchemy construct
|
|
:class:`~sqlalchemy.sql.elements.quoted_name`.
|
|
|
|
"""
|
|
|
|
def drop_column(
|
|
table_name: str, column_name: str, schema: Optional[str] = None, **kw: Any
|
|
) -> Optional[Table]:
|
|
r"""Issue a "drop column" instruction using the current
|
|
migration context.
|
|
|
|
e.g.::
|
|
|
|
drop_column('organization', 'account_id')
|
|
|
|
:param table_name: name of table
|
|
:param column_name: name of column
|
|
:param schema: Optional schema name to operate within. To control
|
|
quoting of the schema outside of the default behavior, use
|
|
the SQLAlchemy construct
|
|
:class:`~sqlalchemy.sql.elements.quoted_name`.
|
|
:param mssql_drop_check: Optional boolean. When ``True``, on
|
|
Microsoft SQL Server only, first
|
|
drop the CHECK constraint on the column using a
|
|
SQL-script-compatible
|
|
block that selects into a @variable from sys.check_constraints,
|
|
then exec's a separate DROP CONSTRAINT for that constraint.
|
|
:param mssql_drop_default: Optional boolean. When ``True``, on
|
|
Microsoft SQL Server only, first
|
|
drop the DEFAULT constraint on the column using a
|
|
SQL-script-compatible
|
|
block that selects into a @variable from sys.default_constraints,
|
|
then exec's a separate DROP CONSTRAINT for that default.
|
|
:param mssql_drop_foreign_key: Optional boolean. When ``True``, on
|
|
Microsoft SQL Server only, first
|
|
drop a single FOREIGN KEY constraint on the column using a
|
|
SQL-script-compatible
|
|
block that selects into a @variable from
|
|
sys.foreign_keys/sys.foreign_key_columns,
|
|
then exec's a separate DROP CONSTRAINT for that default. Only
|
|
works if the column has exactly one FK constraint which refers to
|
|
it, at the moment.
|
|
|
|
"""
|
|
|
|
def drop_constraint(
|
|
constraint_name: str,
|
|
table_name: str,
|
|
type_: Optional[str] = None,
|
|
schema: Optional[str] = None,
|
|
) -> Optional[Table]:
|
|
r"""Drop a constraint of the given name, typically via DROP CONSTRAINT.
|
|
|
|
:param constraint_name: name of the constraint.
|
|
:param table_name: table name.
|
|
:param type\_: optional, required on MySQL. can be
|
|
'foreignkey', 'primary', 'unique', or 'check'.
|
|
:param schema: Optional schema name to operate within. To control
|
|
quoting of the schema outside of the default behavior, use
|
|
the SQLAlchemy construct
|
|
:class:`~sqlalchemy.sql.elements.quoted_name`.
|
|
|
|
"""
|
|
|
|
def drop_index(
|
|
index_name: str,
|
|
table_name: Optional[str] = None,
|
|
schema: Optional[str] = None,
|
|
**kw: Any
|
|
) -> Optional[Table]:
|
|
r"""Issue a "drop index" instruction using the current
|
|
migration context.
|
|
|
|
e.g.::
|
|
|
|
drop_index("accounts")
|
|
|
|
:param index_name: name of the index.
|
|
:param table_name: name of the owning table. Some
|
|
backends such as Microsoft SQL Server require this.
|
|
:param schema: Optional schema name to operate within. To control
|
|
quoting of the schema outside of the default behavior, use
|
|
the SQLAlchemy construct
|
|
:class:`~sqlalchemy.sql.elements.quoted_name`.
|
|
:param \**kw: Additional keyword arguments not mentioned above are
|
|
dialect specific, and passed in the form
|
|
``<dialectname>_<argname>``.
|
|
See the documentation regarding an individual dialect at
|
|
:ref:`dialect_toplevel` for detail on documented arguments.
|
|
|
|
"""
|
|
|
|
def drop_table(
|
|
table_name: str, schema: Optional[str] = None, **kw: Any
|
|
) -> None:
|
|
r"""Issue a "drop table" instruction using the current
|
|
migration context.
|
|
|
|
|
|
e.g.::
|
|
|
|
drop_table("accounts")
|
|
|
|
:param table_name: Name of the table
|
|
:param schema: Optional schema name to operate within. To control
|
|
quoting of the schema outside of the default behavior, use
|
|
the SQLAlchemy construct
|
|
:class:`~sqlalchemy.sql.elements.quoted_name`.
|
|
:param \**kw: Other keyword arguments are passed to the underlying
|
|
:class:`sqlalchemy.schema.Table` object created for the command.
|
|
|
|
"""
|
|
|
|
def drop_table_comment(
|
|
table_name: str,
|
|
existing_comment: Optional[str] = None,
|
|
schema: Optional[str] = None,
|
|
) -> Optional[Table]:
|
|
r"""Issue a "drop table comment" operation to
|
|
remove an existing comment set on a table.
|
|
|
|
.. versionadded:: 1.0.6
|
|
|
|
:param table_name: string name of the target table.
|
|
:param existing_comment: An optional string value of a comment already
|
|
registered on the specified table.
|
|
|
|
.. seealso::
|
|
|
|
:meth:`.Operations.create_table_comment`
|
|
|
|
:paramref:`.Operations.alter_column.comment`
|
|
|
|
"""
|
|
|
|
def execute(
|
|
sqltext: Union[str, TextClause, Update], execution_options: None = None
|
|
) -> Optional[Table]:
|
|
r"""Execute the given SQL using the current migration context.
|
|
|
|
The given SQL can be a plain string, e.g.::
|
|
|
|
op.execute("INSERT INTO table (foo) VALUES ('some value')")
|
|
|
|
Or it can be any kind of Core SQL Expression construct, such as
|
|
below where we use an update construct::
|
|
|
|
from sqlalchemy.sql import table, column
|
|
from sqlalchemy import String
|
|
from alembic import op
|
|
|
|
account = table('account',
|
|
column('name', String)
|
|
)
|
|
op.execute(
|
|
account.update().\\
|
|
where(account.c.name==op.inline_literal('account 1')).\\
|
|
values({'name':op.inline_literal('account 2')})
|
|
)
|
|
|
|
Above, we made use of the SQLAlchemy
|
|
:func:`sqlalchemy.sql.expression.table` and
|
|
:func:`sqlalchemy.sql.expression.column` constructs to make a brief,
|
|
ad-hoc table construct just for our UPDATE statement. A full
|
|
:class:`~sqlalchemy.schema.Table` construct of course works perfectly
|
|
fine as well, though note it's a recommended practice to at least
|
|
ensure the definition of a table is self-contained within the migration
|
|
script, rather than imported from a module that may break compatibility
|
|
with older migrations.
|
|
|
|
In a SQL script context, the statement is emitted directly to the
|
|
output stream. There is *no* return result, however, as this
|
|
function is oriented towards generating a change script
|
|
that can run in "offline" mode. Additionally, parameterized
|
|
statements are discouraged here, as they *will not work* in offline
|
|
mode. Above, we use :meth:`.inline_literal` where parameters are
|
|
to be used.
|
|
|
|
For full interaction with a connected database where parameters can
|
|
also be used normally, use the "bind" available from the context::
|
|
|
|
from alembic import op
|
|
connection = op.get_bind()
|
|
|
|
connection.execute(
|
|
account.update().where(account.c.name=='account 1').
|
|
values({"name": "account 2"})
|
|
)
|
|
|
|
Additionally, when passing the statement as a plain string, it is first
|
|
coerceed into a :func:`sqlalchemy.sql.expression.text` construct
|
|
before being passed along. In the less likely case that the
|
|
literal SQL string contains a colon, it must be escaped with a
|
|
backslash, as::
|
|
|
|
op.execute(r"INSERT INTO table (foo) VALUES ('\:colon_value')")
|
|
|
|
|
|
:param sqltext: Any legal SQLAlchemy expression, including:
|
|
|
|
* a string
|
|
* a :func:`sqlalchemy.sql.expression.text` construct.
|
|
* a :func:`sqlalchemy.sql.expression.insert` construct.
|
|
* a :func:`sqlalchemy.sql.expression.update`,
|
|
:func:`sqlalchemy.sql.expression.insert`,
|
|
or :func:`sqlalchemy.sql.expression.delete` construct.
|
|
* Pretty much anything that's "executable" as described
|
|
in :ref:`sqlexpression_toplevel`.
|
|
|
|
.. note:: when passing a plain string, the statement is coerced into
|
|
a :func:`sqlalchemy.sql.expression.text` construct. This construct
|
|
considers symbols with colons, e.g. ``:foo`` to be bound parameters.
|
|
To avoid this, ensure that colon symbols are escaped, e.g.
|
|
``\:foo``.
|
|
|
|
:param execution_options: Optional dictionary of
|
|
execution options, will be passed to
|
|
:meth:`sqlalchemy.engine.Connection.execution_options`.
|
|
"""
|
|
|
|
def f(name: str) -> conv:
|
|
r"""Indicate a string name that has already had a naming convention
|
|
applied to it.
|
|
|
|
This feature combines with the SQLAlchemy ``naming_convention`` feature
|
|
to disambiguate constraint names that have already had naming
|
|
conventions applied to them, versus those that have not. This is
|
|
necessary in the case that the ``"%(constraint_name)s"`` token
|
|
is used within a naming convention, so that it can be identified
|
|
that this particular name should remain fixed.
|
|
|
|
If the :meth:`.Operations.f` is used on a constraint, the naming
|
|
convention will not take effect::
|
|
|
|
op.add_column('t', 'x', Boolean(name=op.f('ck_bool_t_x')))
|
|
|
|
Above, the CHECK constraint generated will have the name
|
|
``ck_bool_t_x`` regardless of whether or not a naming convention is
|
|
in use.
|
|
|
|
Alternatively, if a naming convention is in use, and 'f' is not used,
|
|
names will be converted along conventions. If the ``target_metadata``
|
|
contains the naming convention
|
|
``{"ck": "ck_bool_%(table_name)s_%(constraint_name)s"}``, then the
|
|
output of the following:
|
|
|
|
op.add_column('t', 'x', Boolean(name='x'))
|
|
|
|
will be::
|
|
|
|
CONSTRAINT ck_bool_t_x CHECK (x in (1, 0)))
|
|
|
|
The function is rendered in the output of autogenerate when
|
|
a particular constraint name is already converted.
|
|
|
|
"""
|
|
|
|
def get_bind() -> Connection:
|
|
r"""Return the current 'bind'.
|
|
|
|
Under normal circumstances, this is the
|
|
:class:`~sqlalchemy.engine.Connection` currently being used
|
|
to emit SQL to the database.
|
|
|
|
In a SQL script context, this value is ``None``. [TODO: verify this]
|
|
|
|
"""
|
|
|
|
def get_context() -> MigrationContext:
|
|
r"""Return the :class:`.MigrationContext` object that's
|
|
currently in use.
|
|
|
|
"""
|
|
|
|
def implementation_for(op_cls: Any) -> Callable[..., Any]:
|
|
r"""Register an implementation for a given :class:`.MigrateOperation`.
|
|
|
|
This is part of the operation extensibility API.
|
|
|
|
.. seealso::
|
|
|
|
:ref:`operation_plugins` - example of use
|
|
|
|
"""
|
|
|
|
def inline_literal(
|
|
value: Union[str, int], type_: None = None
|
|
) -> _literal_bindparam:
|
|
r"""Produce an 'inline literal' expression, suitable for
|
|
using in an INSERT, UPDATE, or DELETE statement.
|
|
|
|
When using Alembic in "offline" mode, CRUD operations
|
|
aren't compatible with SQLAlchemy's default behavior surrounding
|
|
literal values,
|
|
which is that they are converted into bound values and passed
|
|
separately into the ``execute()`` method of the DBAPI cursor.
|
|
An offline SQL
|
|
script needs to have these rendered inline. While it should
|
|
always be noted that inline literal values are an **enormous**
|
|
security hole in an application that handles untrusted input,
|
|
a schema migration is not run in this context, so
|
|
literals are safe to render inline, with the caveat that
|
|
advanced types like dates may not be supported directly
|
|
by SQLAlchemy.
|
|
|
|
See :meth:`.execute` for an example usage of
|
|
:meth:`.inline_literal`.
|
|
|
|
The environment can also be configured to attempt to render
|
|
"literal" values inline automatically, for those simple types
|
|
that are supported by the dialect; see
|
|
:paramref:`.EnvironmentContext.configure.literal_binds` for this
|
|
more recently added feature.
|
|
|
|
:param value: The value to render. Strings, integers, and simple
|
|
numerics should be supported. Other types like boolean,
|
|
dates, etc. may or may not be supported yet by various
|
|
backends.
|
|
:param type\_: optional - a :class:`sqlalchemy.types.TypeEngine`
|
|
subclass stating the type of this value. In SQLAlchemy
|
|
expressions, this is usually derived automatically
|
|
from the Python type of the value itself, as well as
|
|
based on the context in which the value is used.
|
|
|
|
.. seealso::
|
|
|
|
:paramref:`.EnvironmentContext.configure.literal_binds`
|
|
|
|
"""
|
|
|
|
def invoke(operation: MigrateOperation) -> Any:
|
|
r"""Given a :class:`.MigrateOperation`, invoke it in terms of
|
|
this :class:`.Operations` instance.
|
|
|
|
"""
|
|
|
|
def register_operation(
|
|
name: str, sourcename: Optional[str] = None
|
|
) -> Callable[..., Any]:
|
|
r"""Register a new operation for this class.
|
|
|
|
This method is normally used to add new operations
|
|
to the :class:`.Operations` class, and possibly the
|
|
:class:`.BatchOperations` class as well. All Alembic migration
|
|
operations are implemented via this system, however the system
|
|
is also available as a public API to facilitate adding custom
|
|
operations.
|
|
|
|
.. seealso::
|
|
|
|
:ref:`operation_plugins`
|
|
|
|
|
|
"""
|
|
|
|
def rename_table(
|
|
old_table_name: str, new_table_name: str, schema: Optional[str] = None
|
|
) -> Optional[Table]:
|
|
r"""Emit an ALTER TABLE to rename a table.
|
|
|
|
:param old_table_name: old name.
|
|
:param new_table_name: new name.
|
|
:param schema: Optional schema name to operate within. To control
|
|
quoting of the schema outside of the default behavior, use
|
|
the SQLAlchemy construct
|
|
:class:`~sqlalchemy.sql.elements.quoted_name`.
|
|
|
|
"""
|