first add files
This commit is contained in:
85
lib/sqlalchemy/dialects/mssql/__init__.py
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85
lib/sqlalchemy/dialects/mssql/__init__.py
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# mssql/__init__.py
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# Copyright (C) 2005-2022 the SQLAlchemy authors and contributors
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# <see AUTHORS file>
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#
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# This module is part of SQLAlchemy and is released under
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# the MIT License: https://www.opensource.org/licenses/mit-license.php
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from . import base # noqa
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from . import mxodbc # noqa
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from . import pymssql # noqa
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from . import pyodbc # noqa
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from .base import BIGINT
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from .base import BINARY
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from .base import BIT
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from .base import CHAR
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from .base import DATE
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from .base import DATETIME
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from .base import DATETIME2
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from .base import DATETIMEOFFSET
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from .base import DECIMAL
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from .base import FLOAT
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from .base import IMAGE
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from .base import INTEGER
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from .base import JSON
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from .base import MONEY
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from .base import NCHAR
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from .base import NTEXT
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from .base import NUMERIC
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from .base import NVARCHAR
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from .base import REAL
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from .base import ROWVERSION
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from .base import SMALLDATETIME
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from .base import SMALLINT
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from .base import SMALLMONEY
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from .base import SQL_VARIANT
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from .base import TEXT
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from .base import TIME
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from .base import TIMESTAMP
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from .base import TINYINT
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from .base import try_cast
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from .base import UNIQUEIDENTIFIER
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from .base import VARBINARY
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from .base import VARCHAR
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from .base import XML
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base.dialect = dialect = pyodbc.dialect
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__all__ = (
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"JSON",
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"INTEGER",
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"BIGINT",
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"SMALLINT",
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"TINYINT",
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"VARCHAR",
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"NVARCHAR",
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"CHAR",
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"NCHAR",
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"TEXT",
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"NTEXT",
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"DECIMAL",
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"NUMERIC",
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"FLOAT",
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"DATETIME",
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"DATETIME2",
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"DATETIMEOFFSET",
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"DATE",
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"TIME",
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"SMALLDATETIME",
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"BINARY",
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"VARBINARY",
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"BIT",
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"REAL",
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"IMAGE",
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"TIMESTAMP",
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"ROWVERSION",
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"MONEY",
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"SMALLMONEY",
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"UNIQUEIDENTIFIER",
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"SQL_VARIANT",
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"XML",
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"dialect",
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"try_cast",
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)
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3545
lib/sqlalchemy/dialects/mssql/base.py
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3545
lib/sqlalchemy/dialects/mssql/base.py
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File diff suppressed because it is too large
Load Diff
232
lib/sqlalchemy/dialects/mssql/information_schema.py
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232
lib/sqlalchemy/dialects/mssql/information_schema.py
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# mssql/information_schema.py
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# Copyright (C) 2005-2022 the SQLAlchemy authors and contributors
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# <see AUTHORS file>
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#
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# This module is part of SQLAlchemy and is released under
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# the MIT License: https://www.opensource.org/licenses/mit-license.php
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from ... import cast
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from ... import Column
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from ... import MetaData
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from ... import Table
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from ... import util
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from ...ext.compiler import compiles
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from ...sql import expression
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from ...types import Boolean
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from ...types import Integer
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from ...types import Numeric
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from ...types import String
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from ...types import TypeDecorator
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from ...types import Unicode
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ischema = MetaData()
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class CoerceUnicode(TypeDecorator):
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impl = Unicode
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cache_ok = True
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def process_bind_param(self, value, dialect):
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if util.py2k and isinstance(value, util.binary_type):
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value = value.decode(dialect.encoding)
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return value
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def bind_expression(self, bindvalue):
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return _cast_on_2005(bindvalue)
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class _cast_on_2005(expression.ColumnElement):
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def __init__(self, bindvalue):
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self.bindvalue = bindvalue
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@compiles(_cast_on_2005)
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def _compile(element, compiler, **kw):
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from . import base
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if (
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compiler.dialect.server_version_info is None
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or compiler.dialect.server_version_info < base.MS_2005_VERSION
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):
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return compiler.process(element.bindvalue, **kw)
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else:
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return compiler.process(cast(element.bindvalue, Unicode), **kw)
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schemata = Table(
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"SCHEMATA",
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ischema,
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Column("CATALOG_NAME", CoerceUnicode, key="catalog_name"),
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Column("SCHEMA_NAME", CoerceUnicode, key="schema_name"),
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Column("SCHEMA_OWNER", CoerceUnicode, key="schema_owner"),
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schema="INFORMATION_SCHEMA",
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)
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tables = Table(
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"TABLES",
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ischema,
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Column("TABLE_CATALOG", CoerceUnicode, key="table_catalog"),
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Column("TABLE_SCHEMA", CoerceUnicode, key="table_schema"),
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Column("TABLE_NAME", CoerceUnicode, key="table_name"),
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Column("TABLE_TYPE", CoerceUnicode, key="table_type"),
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schema="INFORMATION_SCHEMA",
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)
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columns = Table(
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"COLUMNS",
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ischema,
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Column("TABLE_SCHEMA", CoerceUnicode, key="table_schema"),
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Column("TABLE_NAME", CoerceUnicode, key="table_name"),
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Column("COLUMN_NAME", CoerceUnicode, key="column_name"),
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Column("IS_NULLABLE", Integer, key="is_nullable"),
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Column("DATA_TYPE", String, key="data_type"),
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Column("ORDINAL_POSITION", Integer, key="ordinal_position"),
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Column(
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"CHARACTER_MAXIMUM_LENGTH", Integer, key="character_maximum_length"
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),
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Column("NUMERIC_PRECISION", Integer, key="numeric_precision"),
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Column("NUMERIC_SCALE", Integer, key="numeric_scale"),
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Column("COLUMN_DEFAULT", Integer, key="column_default"),
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Column("COLLATION_NAME", String, key="collation_name"),
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schema="INFORMATION_SCHEMA",
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)
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mssql_temp_table_columns = Table(
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"COLUMNS",
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ischema,
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Column("TABLE_SCHEMA", CoerceUnicode, key="table_schema"),
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Column("TABLE_NAME", CoerceUnicode, key="table_name"),
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Column("COLUMN_NAME", CoerceUnicode, key="column_name"),
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Column("IS_NULLABLE", Integer, key="is_nullable"),
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Column("DATA_TYPE", String, key="data_type"),
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Column("ORDINAL_POSITION", Integer, key="ordinal_position"),
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Column(
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"CHARACTER_MAXIMUM_LENGTH", Integer, key="character_maximum_length"
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),
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Column("NUMERIC_PRECISION", Integer, key="numeric_precision"),
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Column("NUMERIC_SCALE", Integer, key="numeric_scale"),
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Column("COLUMN_DEFAULT", Integer, key="column_default"),
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Column("COLLATION_NAME", String, key="collation_name"),
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schema="tempdb.INFORMATION_SCHEMA",
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)
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constraints = Table(
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"TABLE_CONSTRAINTS",
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ischema,
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Column("TABLE_SCHEMA", CoerceUnicode, key="table_schema"),
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Column("TABLE_NAME", CoerceUnicode, key="table_name"),
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Column("CONSTRAINT_NAME", CoerceUnicode, key="constraint_name"),
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Column("CONSTRAINT_TYPE", CoerceUnicode, key="constraint_type"),
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schema="INFORMATION_SCHEMA",
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)
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column_constraints = Table(
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"CONSTRAINT_COLUMN_USAGE",
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ischema,
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Column("TABLE_SCHEMA", CoerceUnicode, key="table_schema"),
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Column("TABLE_NAME", CoerceUnicode, key="table_name"),
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Column("COLUMN_NAME", CoerceUnicode, key="column_name"),
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Column("CONSTRAINT_NAME", CoerceUnicode, key="constraint_name"),
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schema="INFORMATION_SCHEMA",
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)
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key_constraints = Table(
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"KEY_COLUMN_USAGE",
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ischema,
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Column("TABLE_SCHEMA", CoerceUnicode, key="table_schema"),
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Column("TABLE_NAME", CoerceUnicode, key="table_name"),
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Column("COLUMN_NAME", CoerceUnicode, key="column_name"),
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Column("CONSTRAINT_NAME", CoerceUnicode, key="constraint_name"),
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Column("CONSTRAINT_SCHEMA", CoerceUnicode, key="constraint_schema"),
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Column("ORDINAL_POSITION", Integer, key="ordinal_position"),
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schema="INFORMATION_SCHEMA",
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)
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ref_constraints = Table(
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"REFERENTIAL_CONSTRAINTS",
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ischema,
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Column("CONSTRAINT_CATALOG", CoerceUnicode, key="constraint_catalog"),
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Column("CONSTRAINT_SCHEMA", CoerceUnicode, key="constraint_schema"),
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Column("CONSTRAINT_NAME", CoerceUnicode, key="constraint_name"),
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# TODO: is CATLOG misspelled ?
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Column(
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"UNIQUE_CONSTRAINT_CATLOG",
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CoerceUnicode,
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key="unique_constraint_catalog",
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),
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Column(
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"UNIQUE_CONSTRAINT_SCHEMA",
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CoerceUnicode,
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key="unique_constraint_schema",
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),
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Column(
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"UNIQUE_CONSTRAINT_NAME", CoerceUnicode, key="unique_constraint_name"
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),
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Column("MATCH_OPTION", String, key="match_option"),
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Column("UPDATE_RULE", String, key="update_rule"),
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Column("DELETE_RULE", String, key="delete_rule"),
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schema="INFORMATION_SCHEMA",
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)
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views = Table(
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"VIEWS",
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ischema,
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Column("TABLE_CATALOG", CoerceUnicode, key="table_catalog"),
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Column("TABLE_SCHEMA", CoerceUnicode, key="table_schema"),
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Column("TABLE_NAME", CoerceUnicode, key="table_name"),
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Column("VIEW_DEFINITION", CoerceUnicode, key="view_definition"),
|
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Column("CHECK_OPTION", String, key="check_option"),
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Column("IS_UPDATABLE", String, key="is_updatable"),
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schema="INFORMATION_SCHEMA",
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)
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computed_columns = Table(
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"computed_columns",
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ischema,
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Column("object_id", Integer),
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Column("name", CoerceUnicode),
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Column("is_computed", Boolean),
|
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Column("is_persisted", Boolean),
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Column("definition", CoerceUnicode),
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schema="sys",
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)
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sequences = Table(
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"SEQUENCES",
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ischema,
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Column("SEQUENCE_CATALOG", CoerceUnicode, key="sequence_catalog"),
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Column("SEQUENCE_SCHEMA", CoerceUnicode, key="sequence_schema"),
|
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Column("SEQUENCE_NAME", CoerceUnicode, key="sequence_name"),
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schema="INFORMATION_SCHEMA",
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)
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|
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class IdentitySqlVariant(TypeDecorator):
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r"""This type casts sql_variant columns in the identity_columns view
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to numeric. This is required because:
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|
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* pyodbc does not support sql_variant
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* pymssql under python 2 return the byte representation of the number,
|
||||
int 1 is returned as "\x01\x00\x00\x00". On python 3 it returns the
|
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correct value as string.
|
||||
"""
|
||||
impl = Unicode
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cache_ok = True
|
||||
|
||||
def column_expression(self, colexpr):
|
||||
return cast(colexpr, Numeric)
|
||||
|
||||
|
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identity_columns = Table(
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||||
"identity_columns",
|
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ischema,
|
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Column("object_id", Integer),
|
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Column("name", CoerceUnicode),
|
||||
Column("is_identity", Boolean),
|
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Column("seed_value", IdentitySqlVariant),
|
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Column("increment_value", IdentitySqlVariant),
|
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Column("last_value", IdentitySqlVariant),
|
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Column("is_not_for_replication", Boolean),
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schema="sys",
|
||||
)
|
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125
lib/sqlalchemy/dialects/mssql/json.py
Normal file
125
lib/sqlalchemy/dialects/mssql/json.py
Normal file
@@ -0,0 +1,125 @@
|
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from ... import types as sqltypes
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||||
|
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# technically, all the dialect-specific datatypes that don't have any special
|
||||
# behaviors would be private with names like _MSJson. However, we haven't been
|
||||
# doing this for mysql.JSON or sqlite.JSON which both have JSON / JSONIndexType
|
||||
# / JSONPathType in their json.py files, so keep consistent with that
|
||||
# sub-convention for now. A future change can update them all to be
|
||||
# package-private at once.
|
||||
|
||||
|
||||
class JSON(sqltypes.JSON):
|
||||
"""MSSQL JSON type.
|
||||
|
||||
MSSQL supports JSON-formatted data as of SQL Server 2016.
|
||||
|
||||
The :class:`_mssql.JSON` datatype at the DDL level will represent the
|
||||
datatype as ``NVARCHAR(max)``, but provides for JSON-level comparison
|
||||
functions as well as Python coercion behavior.
|
||||
|
||||
:class:`_mssql.JSON` is used automatically whenever the base
|
||||
:class:`_types.JSON` datatype is used against a SQL Server backend.
|
||||
|
||||
.. seealso::
|
||||
|
||||
:class:`_types.JSON` - main documentation for the generic
|
||||
cross-platform JSON datatype.
|
||||
|
||||
The :class:`_mssql.JSON` type supports persistence of JSON values
|
||||
as well as the core index operations provided by :class:`_types.JSON`
|
||||
datatype, by adapting the operations to render the ``JSON_VALUE``
|
||||
or ``JSON_QUERY`` functions at the database level.
|
||||
|
||||
The SQL Server :class:`_mssql.JSON` type necessarily makes use of the
|
||||
``JSON_QUERY`` and ``JSON_VALUE`` functions when querying for elements
|
||||
of a JSON object. These two functions have a major restriction in that
|
||||
they are **mutually exclusive** based on the type of object to be returned.
|
||||
The ``JSON_QUERY`` function **only** returns a JSON dictionary or list,
|
||||
but not an individual string, numeric, or boolean element; the
|
||||
``JSON_VALUE`` function **only** returns an individual string, numeric,
|
||||
or boolean element. **both functions either return NULL or raise
|
||||
an error if they are not used against the correct expected value**.
|
||||
|
||||
To handle this awkward requirement, indexed access rules are as follows:
|
||||
|
||||
1. When extracting a sub element from a JSON that is itself a JSON
|
||||
dictionary or list, the :meth:`_types.JSON.Comparator.as_json` accessor
|
||||
should be used::
|
||||
|
||||
stmt = select(
|
||||
data_table.c.data["some key"].as_json()
|
||||
).where(
|
||||
data_table.c.data["some key"].as_json() == {"sub": "structure"}
|
||||
)
|
||||
|
||||
2. When extracting a sub element from a JSON that is a plain boolean,
|
||||
string, integer, or float, use the appropriate method among
|
||||
:meth:`_types.JSON.Comparator.as_boolean`,
|
||||
:meth:`_types.JSON.Comparator.as_string`,
|
||||
:meth:`_types.JSON.Comparator.as_integer`,
|
||||
:meth:`_types.JSON.Comparator.as_float`::
|
||||
|
||||
stmt = select(
|
||||
data_table.c.data["some key"].as_string()
|
||||
).where(
|
||||
data_table.c.data["some key"].as_string() == "some string"
|
||||
)
|
||||
|
||||
.. versionadded:: 1.4
|
||||
|
||||
|
||||
"""
|
||||
|
||||
# note there was a result processor here that was looking for "number",
|
||||
# but none of the tests seem to exercise it.
|
||||
|
||||
|
||||
# Note: these objects currently match exactly those of MySQL, however since
|
||||
# these are not generalizable to all JSON implementations, remain separately
|
||||
# implemented for each dialect.
|
||||
class _FormatTypeMixin(object):
|
||||
def _format_value(self, value):
|
||||
raise NotImplementedError()
|
||||
|
||||
def bind_processor(self, dialect):
|
||||
super_proc = self.string_bind_processor(dialect)
|
||||
|
||||
def process(value):
|
||||
value = self._format_value(value)
|
||||
if super_proc:
|
||||
value = super_proc(value)
|
||||
return value
|
||||
|
||||
return process
|
||||
|
||||
def literal_processor(self, dialect):
|
||||
super_proc = self.string_literal_processor(dialect)
|
||||
|
||||
def process(value):
|
||||
value = self._format_value(value)
|
||||
if super_proc:
|
||||
value = super_proc(value)
|
||||
return value
|
||||
|
||||
return process
|
||||
|
||||
|
||||
class JSONIndexType(_FormatTypeMixin, sqltypes.JSON.JSONIndexType):
|
||||
def _format_value(self, value):
|
||||
if isinstance(value, int):
|
||||
value = "$[%s]" % value
|
||||
else:
|
||||
value = '$."%s"' % value
|
||||
return value
|
||||
|
||||
|
||||
class JSONPathType(_FormatTypeMixin, sqltypes.JSON.JSONPathType):
|
||||
def _format_value(self, value):
|
||||
return "$%s" % (
|
||||
"".join(
|
||||
[
|
||||
"[%s]" % elem if isinstance(elem, int) else '."%s"' % elem
|
||||
for elem in value
|
||||
]
|
||||
)
|
||||
)
|
||||
150
lib/sqlalchemy/dialects/mssql/mxodbc.py
Normal file
150
lib/sqlalchemy/dialects/mssql/mxodbc.py
Normal file
@@ -0,0 +1,150 @@
|
||||
# mssql/mxodbc.py
|
||||
# Copyright (C) 2005-2022 the SQLAlchemy authors and contributors
|
||||
# <see AUTHORS file>
|
||||
#
|
||||
# This module is part of SQLAlchemy and is released under
|
||||
# the MIT License: https://www.opensource.org/licenses/mit-license.php
|
||||
|
||||
"""
|
||||
.. dialect:: mssql+mxodbc
|
||||
:name: mxODBC
|
||||
:dbapi: mxodbc
|
||||
:connectstring: mssql+mxodbc://<username>:<password>@<dsnname>
|
||||
:url: https://www.egenix.com/
|
||||
|
||||
.. deprecated:: 1.4 The mxODBC DBAPI is deprecated and will be removed
|
||||
in a future version. Please use one of the supported DBAPIs to
|
||||
connect to mssql.
|
||||
|
||||
Execution Modes
|
||||
---------------
|
||||
|
||||
mxODBC features two styles of statement execution, using the
|
||||
``cursor.execute()`` and ``cursor.executedirect()`` methods (the second being
|
||||
an extension to the DBAPI specification). The former makes use of a particular
|
||||
API call specific to the SQL Server Native Client ODBC driver known
|
||||
SQLDescribeParam, while the latter does not.
|
||||
|
||||
mxODBC apparently only makes repeated use of a single prepared statement
|
||||
when SQLDescribeParam is used. The advantage to prepared statement reuse is
|
||||
one of performance. The disadvantage is that SQLDescribeParam has a limited
|
||||
set of scenarios in which bind parameters are understood, including that they
|
||||
cannot be placed within the argument lists of function calls, anywhere outside
|
||||
the FROM, or even within subqueries within the FROM clause - making the usage
|
||||
of bind parameters within SELECT statements impossible for all but the most
|
||||
simplistic statements.
|
||||
|
||||
For this reason, the mxODBC dialect uses the "native" mode by default only for
|
||||
INSERT, UPDATE, and DELETE statements, and uses the escaped string mode for
|
||||
all other statements.
|
||||
|
||||
This behavior can be controlled via
|
||||
:meth:`~sqlalchemy.sql.expression.Executable.execution_options` using the
|
||||
``native_odbc_execute`` flag with a value of ``True`` or ``False``, where a
|
||||
value of ``True`` will unconditionally use native bind parameters and a value
|
||||
of ``False`` will unconditionally use string-escaped parameters.
|
||||
|
||||
"""
|
||||
|
||||
|
||||
from .base import _MSDate
|
||||
from .base import _MSDateTime
|
||||
from .base import _MSTime
|
||||
from .base import MSDialect
|
||||
from .base import VARBINARY
|
||||
from .pyodbc import _MSNumeric_pyodbc
|
||||
from .pyodbc import MSExecutionContext_pyodbc
|
||||
from ... import types as sqltypes
|
||||
from ...connectors.mxodbc import MxODBCConnector
|
||||
|
||||
|
||||
class _MSNumeric_mxodbc(_MSNumeric_pyodbc):
|
||||
"""Include pyodbc's numeric processor."""
|
||||
|
||||
|
||||
class _MSDate_mxodbc(_MSDate):
|
||||
def bind_processor(self, dialect):
|
||||
def process(value):
|
||||
if value is not None:
|
||||
return "%s-%s-%s" % (value.year, value.month, value.day)
|
||||
else:
|
||||
return None
|
||||
|
||||
return process
|
||||
|
||||
|
||||
class _MSTime_mxodbc(_MSTime):
|
||||
def bind_processor(self, dialect):
|
||||
def process(value):
|
||||
if value is not None:
|
||||
return "%s:%s:%s" % (value.hour, value.minute, value.second)
|
||||
else:
|
||||
return None
|
||||
|
||||
return process
|
||||
|
||||
|
||||
class _VARBINARY_mxodbc(VARBINARY):
|
||||
|
||||
"""
|
||||
mxODBC Support for VARBINARY column types.
|
||||
|
||||
This handles the special case for null VARBINARY values,
|
||||
which maps None values to the mx.ODBC.Manager.BinaryNull symbol.
|
||||
"""
|
||||
|
||||
def bind_processor(self, dialect):
|
||||
if dialect.dbapi is None:
|
||||
return None
|
||||
|
||||
DBAPIBinary = dialect.dbapi.Binary
|
||||
|
||||
def process(value):
|
||||
if value is not None:
|
||||
return DBAPIBinary(value)
|
||||
else:
|
||||
# should pull from mx.ODBC.Manager.BinaryNull
|
||||
return dialect.dbapi.BinaryNull
|
||||
|
||||
return process
|
||||
|
||||
|
||||
class MSExecutionContext_mxodbc(MSExecutionContext_pyodbc):
|
||||
"""
|
||||
The pyodbc execution context is useful for enabling
|
||||
SELECT SCOPE_IDENTITY in cases where OUTPUT clause
|
||||
does not work (tables with insert triggers).
|
||||
"""
|
||||
|
||||
# todo - investigate whether the pyodbc execution context
|
||||
# is really only being used in cases where OUTPUT
|
||||
# won't work.
|
||||
|
||||
|
||||
class MSDialect_mxodbc(MxODBCConnector, MSDialect):
|
||||
|
||||
# this is only needed if "native ODBC" mode is used,
|
||||
# which is now disabled by default.
|
||||
# statement_compiler = MSSQLStrictCompiler
|
||||
supports_statement_cache = True
|
||||
|
||||
execution_ctx_cls = MSExecutionContext_mxodbc
|
||||
|
||||
# flag used by _MSNumeric_mxodbc
|
||||
_need_decimal_fix = True
|
||||
|
||||
colspecs = {
|
||||
sqltypes.Numeric: _MSNumeric_mxodbc,
|
||||
sqltypes.DateTime: _MSDateTime,
|
||||
sqltypes.Date: _MSDate_mxodbc,
|
||||
sqltypes.Time: _MSTime_mxodbc,
|
||||
VARBINARY: _VARBINARY_mxodbc,
|
||||
sqltypes.LargeBinary: _VARBINARY_mxodbc,
|
||||
}
|
||||
|
||||
def __init__(self, description_encoding=None, **params):
|
||||
super(MSDialect_mxodbc, self).__init__(**params)
|
||||
self.description_encoding = description_encoding
|
||||
|
||||
|
||||
dialect = MSDialect_mxodbc
|
||||
116
lib/sqlalchemy/dialects/mssql/provision.py
Normal file
116
lib/sqlalchemy/dialects/mssql/provision.py
Normal file
@@ -0,0 +1,116 @@
|
||||
from sqlalchemy import inspect
|
||||
from sqlalchemy import Integer
|
||||
from ... import create_engine
|
||||
from ... import exc
|
||||
from ...schema import Column
|
||||
from ...schema import DropConstraint
|
||||
from ...schema import ForeignKeyConstraint
|
||||
from ...schema import MetaData
|
||||
from ...schema import Table
|
||||
from ...testing.provision import create_db
|
||||
from ...testing.provision import drop_all_schema_objects_pre_tables
|
||||
from ...testing.provision import drop_db
|
||||
from ...testing.provision import get_temp_table_name
|
||||
from ...testing.provision import log
|
||||
from ...testing.provision import run_reap_dbs
|
||||
from ...testing.provision import temp_table_keyword_args
|
||||
|
||||
|
||||
@create_db.for_db("mssql")
|
||||
def _mssql_create_db(cfg, eng, ident):
|
||||
with eng.connect().execution_options(isolation_level="AUTOCOMMIT") as conn:
|
||||
conn.exec_driver_sql("create database %s" % ident)
|
||||
conn.exec_driver_sql(
|
||||
"ALTER DATABASE %s SET ALLOW_SNAPSHOT_ISOLATION ON" % ident
|
||||
)
|
||||
conn.exec_driver_sql(
|
||||
"ALTER DATABASE %s SET READ_COMMITTED_SNAPSHOT ON" % ident
|
||||
)
|
||||
conn.exec_driver_sql("use %s" % ident)
|
||||
conn.exec_driver_sql("create schema test_schema")
|
||||
conn.exec_driver_sql("create schema test_schema_2")
|
||||
|
||||
|
||||
@drop_db.for_db("mssql")
|
||||
def _mssql_drop_db(cfg, eng, ident):
|
||||
with eng.connect().execution_options(isolation_level="AUTOCOMMIT") as conn:
|
||||
_mssql_drop_ignore(conn, ident)
|
||||
|
||||
|
||||
def _mssql_drop_ignore(conn, ident):
|
||||
try:
|
||||
# typically when this happens, we can't KILL the session anyway,
|
||||
# so let the cleanup process drop the DBs
|
||||
# for row in conn.exec_driver_sql(
|
||||
# "select session_id from sys.dm_exec_sessions "
|
||||
# "where database_id=db_id('%s')" % ident):
|
||||
# log.info("killing SQL server session %s", row['session_id'])
|
||||
# conn.exec_driver_sql("kill %s" % row['session_id'])
|
||||
conn.exec_driver_sql("drop database %s" % ident)
|
||||
log.info("Reaped db: %s", ident)
|
||||
return True
|
||||
except exc.DatabaseError as err:
|
||||
log.warning("couldn't drop db: %s", err)
|
||||
return False
|
||||
|
||||
|
||||
@run_reap_dbs.for_db("mssql")
|
||||
def _reap_mssql_dbs(url, idents):
|
||||
log.info("db reaper connecting to %r", url)
|
||||
eng = create_engine(url)
|
||||
with eng.connect().execution_options(isolation_level="AUTOCOMMIT") as conn:
|
||||
|
||||
log.info("identifiers in file: %s", ", ".join(idents))
|
||||
|
||||
to_reap = conn.exec_driver_sql(
|
||||
"select d.name from sys.databases as d where name "
|
||||
"like 'TEST_%' and not exists (select session_id "
|
||||
"from sys.dm_exec_sessions "
|
||||
"where database_id=d.database_id)"
|
||||
)
|
||||
all_names = {dbname.lower() for (dbname,) in to_reap}
|
||||
to_drop = set()
|
||||
for name in all_names:
|
||||
if name in idents:
|
||||
to_drop.add(name)
|
||||
|
||||
dropped = total = 0
|
||||
for total, dbname in enumerate(to_drop, 1):
|
||||
if _mssql_drop_ignore(conn, dbname):
|
||||
dropped += 1
|
||||
log.info(
|
||||
"Dropped %d out of %d stale databases detected", dropped, total
|
||||
)
|
||||
|
||||
|
||||
@temp_table_keyword_args.for_db("mssql")
|
||||
def _mssql_temp_table_keyword_args(cfg, eng):
|
||||
return {}
|
||||
|
||||
|
||||
@get_temp_table_name.for_db("mssql")
|
||||
def _mssql_get_temp_table_name(cfg, eng, base_name):
|
||||
return "##" + base_name
|
||||
|
||||
|
||||
@drop_all_schema_objects_pre_tables.for_db("mssql")
|
||||
def drop_all_schema_objects_pre_tables(cfg, eng):
|
||||
with eng.connect().execution_options(isolation_level="AUTOCOMMIT") as conn:
|
||||
inspector = inspect(conn)
|
||||
for schema in (None, "dbo", cfg.test_schema, cfg.test_schema_2):
|
||||
for tname in inspector.get_table_names(schema=schema):
|
||||
tb = Table(
|
||||
tname,
|
||||
MetaData(),
|
||||
Column("x", Integer),
|
||||
Column("y", Integer),
|
||||
schema=schema,
|
||||
)
|
||||
for fk in inspect(conn).get_foreign_keys(tname, schema=schema):
|
||||
conn.execute(
|
||||
DropConstraint(
|
||||
ForeignKeyConstraint(
|
||||
[tb.c.x], [tb.c.y], name=fk["name"]
|
||||
)
|
||||
)
|
||||
)
|
||||
138
lib/sqlalchemy/dialects/mssql/pymssql.py
Normal file
138
lib/sqlalchemy/dialects/mssql/pymssql.py
Normal file
@@ -0,0 +1,138 @@
|
||||
# mssql/pymssql.py
|
||||
# Copyright (C) 2005-2022 the SQLAlchemy authors and contributors
|
||||
# <see AUTHORS file>
|
||||
#
|
||||
# This module is part of SQLAlchemy and is released under
|
||||
# the MIT License: https://www.opensource.org/licenses/mit-license.php
|
||||
|
||||
"""
|
||||
.. dialect:: mssql+pymssql
|
||||
:name: pymssql
|
||||
:dbapi: pymssql
|
||||
:connectstring: mssql+pymssql://<username>:<password>@<freetds_name>/?charset=utf8
|
||||
|
||||
pymssql is a Python module that provides a Python DBAPI interface around
|
||||
`FreeTDS <https://www.freetds.org/>`_.
|
||||
|
||||
.. note::
|
||||
|
||||
pymssql is currently not included in SQLAlchemy's continuous integration
|
||||
(CI) testing.
|
||||
|
||||
Modern versions of this driver worked very well with SQL Server and FreeTDS
|
||||
from Linux and were highly recommended. However, pymssql is currently
|
||||
unmaintained and has fallen behind the progress of the Microsoft ODBC driver in
|
||||
its support for newer features of SQL Server. The latest official release of
|
||||
pymssql at the time of this document is version 2.1.4 (August, 2018) and it
|
||||
lacks support for:
|
||||
|
||||
1. table-valued parameters (TVPs),
|
||||
2. ``datetimeoffset`` columns using timezone-aware ``datetime`` objects
|
||||
(values are sent and retrieved as strings), and
|
||||
3. encrypted connections (e.g., to Azure SQL), when pymssql is installed from
|
||||
the pre-built wheels. Support for encrypted connections requires building
|
||||
pymssql from source, which can be a nuisance, especially under Windows.
|
||||
|
||||
The above features are all supported by mssql+pyodbc when using Microsoft's
|
||||
ODBC Driver for SQL Server (msodbcsql), which is now available for Windows,
|
||||
(several flavors of) Linux, and macOS.
|
||||
|
||||
|
||||
""" # noqa
|
||||
import re
|
||||
|
||||
from .base import MSDialect
|
||||
from .base import MSIdentifierPreparer
|
||||
from ... import processors
|
||||
from ... import types as sqltypes
|
||||
from ... import util
|
||||
|
||||
|
||||
class _MSNumeric_pymssql(sqltypes.Numeric):
|
||||
def result_processor(self, dialect, type_):
|
||||
if not self.asdecimal:
|
||||
return processors.to_float
|
||||
else:
|
||||
return sqltypes.Numeric.result_processor(self, dialect, type_)
|
||||
|
||||
|
||||
class MSIdentifierPreparer_pymssql(MSIdentifierPreparer):
|
||||
def __init__(self, dialect):
|
||||
super(MSIdentifierPreparer_pymssql, self).__init__(dialect)
|
||||
# pymssql has the very unusual behavior that it uses pyformat
|
||||
# yet does not require that percent signs be doubled
|
||||
self._double_percents = False
|
||||
|
||||
|
||||
class MSDialect_pymssql(MSDialect):
|
||||
supports_statement_cache = True
|
||||
supports_native_decimal = True
|
||||
driver = "pymssql"
|
||||
|
||||
preparer = MSIdentifierPreparer_pymssql
|
||||
|
||||
colspecs = util.update_copy(
|
||||
MSDialect.colspecs,
|
||||
{sqltypes.Numeric: _MSNumeric_pymssql, sqltypes.Float: sqltypes.Float},
|
||||
)
|
||||
|
||||
@classmethod
|
||||
def dbapi(cls):
|
||||
module = __import__("pymssql")
|
||||
# pymmsql < 2.1.1 doesn't have a Binary method. we use string
|
||||
client_ver = tuple(int(x) for x in module.__version__.split("."))
|
||||
if client_ver < (2, 1, 1):
|
||||
# TODO: monkeypatching here is less than ideal
|
||||
module.Binary = lambda x: x if hasattr(x, "decode") else str(x)
|
||||
|
||||
if client_ver < (1,):
|
||||
util.warn(
|
||||
"The pymssql dialect expects at least "
|
||||
"the 1.0 series of the pymssql DBAPI."
|
||||
)
|
||||
return module
|
||||
|
||||
def _get_server_version_info(self, connection):
|
||||
vers = connection.exec_driver_sql("select @@version").scalar()
|
||||
m = re.match(r"Microsoft .*? - (\d+)\.(\d+)\.(\d+)\.(\d+)", vers)
|
||||
if m:
|
||||
return tuple(int(x) for x in m.group(1, 2, 3, 4))
|
||||
else:
|
||||
return None
|
||||
|
||||
def create_connect_args(self, url):
|
||||
opts = url.translate_connect_args(username="user")
|
||||
opts.update(url.query)
|
||||
port = opts.pop("port", None)
|
||||
if port and "host" in opts:
|
||||
opts["host"] = "%s:%s" % (opts["host"], port)
|
||||
return [[], opts]
|
||||
|
||||
def is_disconnect(self, e, connection, cursor):
|
||||
for msg in (
|
||||
"Adaptive Server connection timed out",
|
||||
"Net-Lib error during Connection reset by peer",
|
||||
"message 20003", # connection timeout
|
||||
"Error 10054",
|
||||
"Not connected to any MS SQL server",
|
||||
"Connection is closed",
|
||||
"message 20006", # Write to the server failed
|
||||
"message 20017", # Unexpected EOF from the server
|
||||
"message 20047", # DBPROCESS is dead or not enabled
|
||||
):
|
||||
if msg in str(e):
|
||||
return True
|
||||
else:
|
||||
return False
|
||||
|
||||
def set_isolation_level(self, connection, level):
|
||||
if level == "AUTOCOMMIT":
|
||||
connection.autocommit(True)
|
||||
else:
|
||||
connection.autocommit(False)
|
||||
super(MSDialect_pymssql, self).set_isolation_level(
|
||||
connection, level
|
||||
)
|
||||
|
||||
|
||||
dialect = MSDialect_pymssql
|
||||
673
lib/sqlalchemy/dialects/mssql/pyodbc.py
Normal file
673
lib/sqlalchemy/dialects/mssql/pyodbc.py
Normal file
@@ -0,0 +1,673 @@
|
||||
# mssql/pyodbc.py
|
||||
# Copyright (C) 2005-2022 the SQLAlchemy authors and contributors
|
||||
# <see AUTHORS file>
|
||||
#
|
||||
# This module is part of SQLAlchemy and is released under
|
||||
# the MIT License: https://www.opensource.org/licenses/mit-license.php
|
||||
r"""
|
||||
.. dialect:: mssql+pyodbc
|
||||
:name: PyODBC
|
||||
:dbapi: pyodbc
|
||||
:connectstring: mssql+pyodbc://<username>:<password>@<dsnname>
|
||||
:url: https://pypi.org/project/pyodbc/
|
||||
|
||||
Connecting to PyODBC
|
||||
--------------------
|
||||
|
||||
The URL here is to be translated to PyODBC connection strings, as
|
||||
detailed in `ConnectionStrings <https://code.google.com/p/pyodbc/wiki/ConnectionStrings>`_.
|
||||
|
||||
DSN Connections
|
||||
^^^^^^^^^^^^^^^
|
||||
|
||||
A DSN connection in ODBC means that a pre-existing ODBC datasource is
|
||||
configured on the client machine. The application then specifies the name
|
||||
of this datasource, which encompasses details such as the specific ODBC driver
|
||||
in use as well as the network address of the database. Assuming a datasource
|
||||
is configured on the client, a basic DSN-based connection looks like::
|
||||
|
||||
engine = create_engine("mssql+pyodbc://scott:tiger@some_dsn")
|
||||
|
||||
Which above, will pass the following connection string to PyODBC::
|
||||
|
||||
DSN=some_dsn;UID=scott;PWD=tiger
|
||||
|
||||
If the username and password are omitted, the DSN form will also add
|
||||
the ``Trusted_Connection=yes`` directive to the ODBC string.
|
||||
|
||||
Hostname Connections
|
||||
^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
Hostname-based connections are also supported by pyodbc. These are often
|
||||
easier to use than a DSN and have the additional advantage that the specific
|
||||
database name to connect towards may be specified locally in the URL, rather
|
||||
than it being fixed as part of a datasource configuration.
|
||||
|
||||
When using a hostname connection, the driver name must also be specified in the
|
||||
query parameters of the URL. As these names usually have spaces in them, the
|
||||
name must be URL encoded which means using plus signs for spaces::
|
||||
|
||||
engine = create_engine("mssql+pyodbc://scott:tiger@myhost:port/databasename?driver=ODBC+Driver+17+for+SQL+Server")
|
||||
|
||||
Other keywords interpreted by the Pyodbc dialect to be passed to
|
||||
``pyodbc.connect()`` in both the DSN and hostname cases include:
|
||||
``odbc_autotranslate``, ``ansi``, ``unicode_results``, ``autocommit``,
|
||||
``authentication``.
|
||||
Note that in order for the dialect to recognize these keywords
|
||||
(including the ``driver`` keyword above) they must be all lowercase.
|
||||
Multiple additional keyword arguments must be separated by an
|
||||
ampersand (``&``), not a semicolon::
|
||||
|
||||
engine = create_engine(
|
||||
"mssql+pyodbc://scott:tiger@myhost:49242/databasename"
|
||||
"?driver=ODBC+Driver+17+for+SQL+Server"
|
||||
"&authentication=ActiveDirectoryIntegrated"
|
||||
)
|
||||
|
||||
The equivalent URL can be constructed using :class:`_sa.engine.URL`::
|
||||
|
||||
from sqlalchemy.engine import URL
|
||||
connection_url = URL.create(
|
||||
"mssql+pyodbc",
|
||||
username="scott",
|
||||
password="tiger",
|
||||
host="myhost",
|
||||
port=49242,
|
||||
database="databasename",
|
||||
query={
|
||||
"driver": "ODBC Driver 17 for SQL Server",
|
||||
"authentication": "ActiveDirectoryIntegrated",
|
||||
},
|
||||
)
|
||||
|
||||
|
||||
Pass through exact Pyodbc string
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
A PyODBC connection string can also be sent in pyodbc's format directly, as
|
||||
specified in `the PyODBC documentation
|
||||
<https://github.com/mkleehammer/pyodbc/wiki/Connecting-to-databases>`_,
|
||||
using the parameter ``odbc_connect``. A :class:`_sa.engine.URL` object
|
||||
can help make this easier::
|
||||
|
||||
from sqlalchemy.engine import URL
|
||||
connection_string = "DRIVER={SQL Server Native Client 10.0};SERVER=dagger;DATABASE=test;UID=user;PWD=password"
|
||||
connection_url = URL.create("mssql+pyodbc", query={"odbc_connect": connection_string})
|
||||
|
||||
engine = create_engine(connection_url)
|
||||
|
||||
.. _mssql_pyodbc_access_tokens:
|
||||
|
||||
Connecting to databases with access tokens
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
Some database servers are set up to only accept access tokens for login. For
|
||||
example, SQL Server allows the use of Azure Active Directory tokens to connect
|
||||
to databases. This requires creating a credential object using the
|
||||
``azure-identity`` library. More information about the authentication step can be
|
||||
found in `Microsoft's documentation
|
||||
<https://docs.microsoft.com/en-us/azure/developer/python/azure-sdk-authenticate?tabs=bash>`_.
|
||||
|
||||
After getting an engine, the credentials need to be sent to ``pyodbc.connect``
|
||||
each time a connection is requested. One way to do this is to set up an event
|
||||
listener on the engine that adds the credential token to the dialect's connect
|
||||
call. This is discussed more generally in :ref:`engines_dynamic_tokens`. For
|
||||
SQL Server in particular, this is passed as an ODBC connection attribute with
|
||||
a data structure `described by Microsoft
|
||||
<https://docs.microsoft.com/en-us/sql/connect/odbc/using-azure-active-directory#authenticating-with-an-access-token>`_.
|
||||
|
||||
The following code snippet will create an engine that connects to an Azure SQL
|
||||
database using Azure credentials::
|
||||
|
||||
import struct
|
||||
from sqlalchemy import create_engine, event
|
||||
from sqlalchemy.engine.url import URL
|
||||
from azure import identity
|
||||
|
||||
SQL_COPT_SS_ACCESS_TOKEN = 1256 # Connection option for access tokens, as defined in msodbcsql.h
|
||||
TOKEN_URL = "https://database.windows.net/" # The token URL for any Azure SQL database
|
||||
|
||||
connection_string = "mssql+pyodbc://@my-server.database.windows.net/myDb?driver=ODBC+Driver+17+for+SQL+Server"
|
||||
|
||||
engine = create_engine(connection_string)
|
||||
|
||||
azure_credentials = identity.DefaultAzureCredential()
|
||||
|
||||
@event.listens_for(engine, "do_connect")
|
||||
def provide_token(dialect, conn_rec, cargs, cparams):
|
||||
# remove the "Trusted_Connection" parameter that SQLAlchemy adds
|
||||
cargs[0] = cargs[0].replace(";Trusted_Connection=Yes", "")
|
||||
|
||||
# create token credential
|
||||
raw_token = azure_credentials.get_token(TOKEN_URL).token.encode("utf-16-le")
|
||||
token_struct = struct.pack(f"<I{len(raw_token)}s", len(raw_token), raw_token)
|
||||
|
||||
# apply it to keyword arguments
|
||||
cparams["attrs_before"] = {SQL_COPT_SS_ACCESS_TOKEN: token_struct}
|
||||
|
||||
.. tip::
|
||||
|
||||
The ``Trusted_Connection`` token is currently added by the SQLAlchemy
|
||||
pyodbc dialect when no username or password is present. This needs
|
||||
to be removed per Microsoft's
|
||||
`documentation for Azure access tokens
|
||||
<https://docs.microsoft.com/en-us/sql/connect/odbc/using-azure-active-directory#authenticating-with-an-access-token>`_,
|
||||
stating that a connection string when using an access token must not contain
|
||||
``UID``, ``PWD``, ``Authentication`` or ``Trusted_Connection`` parameters.
|
||||
|
||||
.. _azure_synapse_ignore_no_transaction_on_rollback:
|
||||
|
||||
Avoiding transaction-related exceptions on Azure Synapse Analytics
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
Azure Synapse Analytics has a significant difference in its transaction
|
||||
handling compared to plain SQL Server; in some cases an error within a Synapse
|
||||
transaction can cause it to be arbitrarily terminated on the server side, which
|
||||
then causes the DBAPI ``.rollback()`` method (as well as ``.commit()``) to
|
||||
fail. The issue prevents the usual DBAPI contract of allowing ``.rollback()``
|
||||
to pass silently if no transaction is present as the driver does not expect
|
||||
this condition. The symptom of this failure is an exception with a message
|
||||
resembling 'No corresponding transaction found. (111214)' when attempting to
|
||||
emit a ``.rollback()`` after an operation had a failure of some kind.
|
||||
|
||||
This specific case can be handled by passing ``ignore_no_transaction_on_rollback=True`` to
|
||||
the SQL Server dialect via the :func:`_sa.create_engine` function as follows::
|
||||
|
||||
engine = create_engine(connection_url, ignore_no_transaction_on_rollback=True)
|
||||
|
||||
Using the above parameter, the dialect will catch ``ProgrammingError``
|
||||
exceptions raised during ``connection.rollback()`` and emit a warning
|
||||
if the error message contains code ``111214``, however will not raise
|
||||
an exception.
|
||||
|
||||
.. versionadded:: 1.4.40 Added the
|
||||
``ignore_no_transaction_on_rollback=True`` parameter.
|
||||
|
||||
Enable autocommit for Azure SQL Data Warehouse (DW) connections
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
Azure SQL Data Warehouse does not support transactions,
|
||||
and that can cause problems with SQLAlchemy's "autobegin" (and implicit
|
||||
commit/rollback) behavior. We can avoid these problems by enabling autocommit
|
||||
at both the pyodbc and engine levels::
|
||||
|
||||
connection_url = sa.engine.URL.create(
|
||||
"mssql+pyodbc",
|
||||
username="scott",
|
||||
password="tiger",
|
||||
host="dw.azure.example.com",
|
||||
database="mydb",
|
||||
query={
|
||||
"driver": "ODBC Driver 17 for SQL Server",
|
||||
"autocommit": "True",
|
||||
},
|
||||
)
|
||||
|
||||
engine = create_engine(connection_url).execution_options(
|
||||
isolation_level="AUTOCOMMIT"
|
||||
)
|
||||
|
||||
Avoiding sending large string parameters as TEXT/NTEXT
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
By default, for historical reasons, Microsoft's ODBC drivers for SQL Server
|
||||
send long string parameters (greater than 4000 SBCS characters or 2000 Unicode
|
||||
characters) as TEXT/NTEXT values. TEXT and NTEXT have been deprecated for many
|
||||
years and are starting to cause compatibility issues with newer versions of
|
||||
SQL_Server/Azure. For example, see `this
|
||||
issue <https://github.com/mkleehammer/pyodbc/issues/835>`_.
|
||||
|
||||
Starting with ODBC Driver 18 for SQL Server we can override the legacy
|
||||
behavior and pass long strings as varchar(max)/nvarchar(max) using the
|
||||
``LongAsMax=Yes`` connection string parameter::
|
||||
|
||||
connection_url = sa.engine.URL.create(
|
||||
"mssql+pyodbc",
|
||||
username="scott",
|
||||
password="tiger",
|
||||
host="mssqlserver.example.com",
|
||||
database="mydb",
|
||||
query={
|
||||
"driver": "ODBC Driver 18 for SQL Server",
|
||||
"LongAsMax": "Yes",
|
||||
},
|
||||
)
|
||||
|
||||
|
||||
Pyodbc Pooling / connection close behavior
|
||||
------------------------------------------
|
||||
|
||||
PyODBC uses internal `pooling
|
||||
<https://github.com/mkleehammer/pyodbc/wiki/The-pyodbc-Module#pooling>`_ by
|
||||
default, which means connections will be longer lived than they are within
|
||||
SQLAlchemy itself. As SQLAlchemy has its own pooling behavior, it is often
|
||||
preferable to disable this behavior. This behavior can only be disabled
|
||||
globally at the PyODBC module level, **before** any connections are made::
|
||||
|
||||
import pyodbc
|
||||
|
||||
pyodbc.pooling = False
|
||||
|
||||
# don't use the engine before pooling is set to False
|
||||
engine = create_engine("mssql+pyodbc://user:pass@dsn")
|
||||
|
||||
If this variable is left at its default value of ``True``, **the application
|
||||
will continue to maintain active database connections**, even when the
|
||||
SQLAlchemy engine itself fully discards a connection or if the engine is
|
||||
disposed.
|
||||
|
||||
.. seealso::
|
||||
|
||||
`pooling <https://github.com/mkleehammer/pyodbc/wiki/The-pyodbc-Module#pooling>`_ -
|
||||
in the PyODBC documentation.
|
||||
|
||||
Driver / Unicode Support
|
||||
-------------------------
|
||||
|
||||
PyODBC works best with Microsoft ODBC drivers, particularly in the area
|
||||
of Unicode support on both Python 2 and Python 3.
|
||||
|
||||
Using the FreeTDS ODBC drivers on Linux or OSX with PyODBC is **not**
|
||||
recommended; there have been historically many Unicode-related issues
|
||||
in this area, including before Microsoft offered ODBC drivers for Linux
|
||||
and OSX. Now that Microsoft offers drivers for all platforms, for
|
||||
PyODBC support these are recommended. FreeTDS remains relevant for
|
||||
non-ODBC drivers such as pymssql where it works very well.
|
||||
|
||||
|
||||
Rowcount Support
|
||||
----------------
|
||||
|
||||
Pyodbc only has partial support for rowcount. See the notes at
|
||||
:ref:`mssql_rowcount_versioning` for important notes when using ORM
|
||||
versioning.
|
||||
|
||||
.. _mssql_pyodbc_fastexecutemany:
|
||||
|
||||
Fast Executemany Mode
|
||||
---------------------
|
||||
|
||||
The Pyodbc driver has added support for a "fast executemany" mode of execution
|
||||
which greatly reduces round trips for a DBAPI ``executemany()`` call when using
|
||||
Microsoft ODBC drivers, for **limited size batches that fit in memory**. The
|
||||
feature is enabled by setting the flag ``.fast_executemany`` on the DBAPI
|
||||
cursor when an executemany call is to be used. The SQLAlchemy pyodbc SQL
|
||||
Server dialect supports setting this flag automatically when the
|
||||
``.fast_executemany`` flag is passed to
|
||||
:func:`_sa.create_engine` ; note that the ODBC driver must be the Microsoft
|
||||
driver in order to use this flag::
|
||||
|
||||
engine = create_engine(
|
||||
"mssql+pyodbc://scott:tiger@mssql2017:1433/test?driver=ODBC+Driver+13+for+SQL+Server",
|
||||
fast_executemany=True)
|
||||
|
||||
.. warning:: The pyodbc fast_executemany mode **buffers all rows in memory** and is
|
||||
not compatible with very large batches of data. A future version of SQLAlchemy
|
||||
may support this flag as a per-execution option instead.
|
||||
|
||||
.. versionadded:: 1.3
|
||||
|
||||
.. seealso::
|
||||
|
||||
`fast executemany <https://github.com/mkleehammer/pyodbc/wiki/Features-beyond-the-DB-API#fast_executemany>`_
|
||||
- on github
|
||||
|
||||
.. _mssql_pyodbc_setinputsizes:
|
||||
|
||||
Setinputsizes Support
|
||||
-----------------------
|
||||
|
||||
The pyodbc ``cursor.setinputsizes()`` method can be used if necessary. To
|
||||
enable this hook, pass ``use_setinputsizes=True`` to :func:`_sa.create_engine`::
|
||||
|
||||
engine = create_engine("mssql+pyodbc://...", use_setinputsizes=True)
|
||||
|
||||
The behavior of the hook can then be customized, as may be necessary
|
||||
particularly if fast_executemany is in use, via the
|
||||
:meth:`.DialectEvents.do_setinputsizes` hook. See that method for usage
|
||||
examples.
|
||||
|
||||
.. versionchanged:: 1.4.1 The pyodbc dialects will not use setinputsizes
|
||||
unless ``use_setinputsizes=True`` is passed.
|
||||
|
||||
""" # noqa
|
||||
|
||||
|
||||
import datetime
|
||||
import decimal
|
||||
import re
|
||||
import struct
|
||||
|
||||
from .base import BINARY
|
||||
from .base import DATETIMEOFFSET
|
||||
from .base import MSDialect
|
||||
from .base import MSExecutionContext
|
||||
from .base import VARBINARY
|
||||
from ... import exc
|
||||
from ... import types as sqltypes
|
||||
from ... import util
|
||||
from ...connectors.pyodbc import PyODBCConnector
|
||||
|
||||
|
||||
class _ms_numeric_pyodbc(object):
|
||||
|
||||
"""Turns Decimals with adjusted() < 0 or > 7 into strings.
|
||||
|
||||
The routines here are needed for older pyodbc versions
|
||||
as well as current mxODBC versions.
|
||||
|
||||
"""
|
||||
|
||||
def bind_processor(self, dialect):
|
||||
|
||||
super_process = super(_ms_numeric_pyodbc, self).bind_processor(dialect)
|
||||
|
||||
if not dialect._need_decimal_fix:
|
||||
return super_process
|
||||
|
||||
def process(value):
|
||||
if self.asdecimal and isinstance(value, decimal.Decimal):
|
||||
adjusted = value.adjusted()
|
||||
if adjusted < 0:
|
||||
return self._small_dec_to_string(value)
|
||||
elif adjusted > 7:
|
||||
return self._large_dec_to_string(value)
|
||||
|
||||
if super_process:
|
||||
return super_process(value)
|
||||
else:
|
||||
return value
|
||||
|
||||
return process
|
||||
|
||||
# these routines needed for older versions of pyodbc.
|
||||
# as of 2.1.8 this logic is integrated.
|
||||
|
||||
def _small_dec_to_string(self, value):
|
||||
return "%s0.%s%s" % (
|
||||
(value < 0 and "-" or ""),
|
||||
"0" * (abs(value.adjusted()) - 1),
|
||||
"".join([str(nint) for nint in value.as_tuple()[1]]),
|
||||
)
|
||||
|
||||
def _large_dec_to_string(self, value):
|
||||
_int = value.as_tuple()[1]
|
||||
if "E" in str(value):
|
||||
result = "%s%s%s" % (
|
||||
(value < 0 and "-" or ""),
|
||||
"".join([str(s) for s in _int]),
|
||||
"0" * (value.adjusted() - (len(_int) - 1)),
|
||||
)
|
||||
else:
|
||||
if (len(_int) - 1) > value.adjusted():
|
||||
result = "%s%s.%s" % (
|
||||
(value < 0 and "-" or ""),
|
||||
"".join([str(s) for s in _int][0 : value.adjusted() + 1]),
|
||||
"".join([str(s) for s in _int][value.adjusted() + 1 :]),
|
||||
)
|
||||
else:
|
||||
result = "%s%s" % (
|
||||
(value < 0 and "-" or ""),
|
||||
"".join([str(s) for s in _int][0 : value.adjusted() + 1]),
|
||||
)
|
||||
return result
|
||||
|
||||
|
||||
class _MSNumeric_pyodbc(_ms_numeric_pyodbc, sqltypes.Numeric):
|
||||
pass
|
||||
|
||||
|
||||
class _MSFloat_pyodbc(_ms_numeric_pyodbc, sqltypes.Float):
|
||||
pass
|
||||
|
||||
|
||||
class _ms_binary_pyodbc(object):
|
||||
"""Wraps binary values in dialect-specific Binary wrapper.
|
||||
If the value is null, return a pyodbc-specific BinaryNull
|
||||
object to prevent pyODBC [and FreeTDS] from defaulting binary
|
||||
NULL types to SQLWCHAR and causing implicit conversion errors.
|
||||
"""
|
||||
|
||||
def bind_processor(self, dialect):
|
||||
if dialect.dbapi is None:
|
||||
return None
|
||||
|
||||
DBAPIBinary = dialect.dbapi.Binary
|
||||
|
||||
def process(value):
|
||||
if value is not None:
|
||||
return DBAPIBinary(value)
|
||||
else:
|
||||
# pyodbc-specific
|
||||
return dialect.dbapi.BinaryNull
|
||||
|
||||
return process
|
||||
|
||||
|
||||
class _ODBCDateTimeBindProcessor(object):
|
||||
"""Add bind processors to handle datetimeoffset behaviors"""
|
||||
|
||||
has_tz = False
|
||||
|
||||
def bind_processor(self, dialect):
|
||||
def process(value):
|
||||
if value is None:
|
||||
return None
|
||||
elif isinstance(value, util.string_types):
|
||||
# if a string was passed directly, allow it through
|
||||
return value
|
||||
elif not value.tzinfo or (not self.timezone and not self.has_tz):
|
||||
# for DateTime(timezone=False)
|
||||
return value
|
||||
else:
|
||||
# for DATETIMEOFFSET or DateTime(timezone=True)
|
||||
#
|
||||
# Convert to string format required by T-SQL
|
||||
dto_string = value.strftime("%Y-%m-%d %H:%M:%S.%f %z")
|
||||
# offset needs a colon, e.g., -0700 -> -07:00
|
||||
# "UTC offset in the form (+-)HHMM[SS[.ffffff]]"
|
||||
# backend currently rejects seconds / fractional seconds
|
||||
dto_string = re.sub(
|
||||
r"([\+\-]\d{2})([\d\.]+)$", r"\1:\2", dto_string
|
||||
)
|
||||
return dto_string
|
||||
|
||||
return process
|
||||
|
||||
|
||||
class _ODBCDateTime(_ODBCDateTimeBindProcessor, sqltypes.DateTime):
|
||||
pass
|
||||
|
||||
|
||||
class _ODBCDATETIMEOFFSET(_ODBCDateTimeBindProcessor, DATETIMEOFFSET):
|
||||
has_tz = True
|
||||
|
||||
|
||||
class _VARBINARY_pyodbc(_ms_binary_pyodbc, VARBINARY):
|
||||
pass
|
||||
|
||||
|
||||
class _BINARY_pyodbc(_ms_binary_pyodbc, BINARY):
|
||||
pass
|
||||
|
||||
|
||||
class MSExecutionContext_pyodbc(MSExecutionContext):
|
||||
_embedded_scope_identity = False
|
||||
|
||||
def pre_exec(self):
|
||||
"""where appropriate, issue "select scope_identity()" in the same
|
||||
statement.
|
||||
|
||||
Background on why "scope_identity()" is preferable to "@@identity":
|
||||
https://msdn.microsoft.com/en-us/library/ms190315.aspx
|
||||
|
||||
Background on why we attempt to embed "scope_identity()" into the same
|
||||
statement as the INSERT:
|
||||
https://code.google.com/p/pyodbc/wiki/FAQs#How_do_I_retrieve_autogenerated/identity_values?
|
||||
|
||||
"""
|
||||
|
||||
super(MSExecutionContext_pyodbc, self).pre_exec()
|
||||
|
||||
# don't embed the scope_identity select into an
|
||||
# "INSERT .. DEFAULT VALUES"
|
||||
if (
|
||||
self._select_lastrowid
|
||||
and self.dialect.use_scope_identity
|
||||
and len(self.parameters[0])
|
||||
):
|
||||
self._embedded_scope_identity = True
|
||||
|
||||
self.statement += "; select scope_identity()"
|
||||
|
||||
def post_exec(self):
|
||||
if self._embedded_scope_identity:
|
||||
# Fetch the last inserted id from the manipulated statement
|
||||
# We may have to skip over a number of result sets with
|
||||
# no data (due to triggers, etc.)
|
||||
while True:
|
||||
try:
|
||||
# fetchall() ensures the cursor is consumed
|
||||
# without closing it (FreeTDS particularly)
|
||||
row = self.cursor.fetchall()[0]
|
||||
break
|
||||
except self.dialect.dbapi.Error:
|
||||
# no way around this - nextset() consumes the previous set
|
||||
# so we need to just keep flipping
|
||||
self.cursor.nextset()
|
||||
|
||||
self._lastrowid = int(row[0])
|
||||
else:
|
||||
super(MSExecutionContext_pyodbc, self).post_exec()
|
||||
|
||||
|
||||
class MSDialect_pyodbc(PyODBCConnector, MSDialect):
|
||||
supports_statement_cache = True
|
||||
|
||||
# mssql still has problems with this on Linux
|
||||
supports_sane_rowcount_returning = False
|
||||
|
||||
execution_ctx_cls = MSExecutionContext_pyodbc
|
||||
|
||||
colspecs = util.update_copy(
|
||||
MSDialect.colspecs,
|
||||
{
|
||||
sqltypes.Numeric: _MSNumeric_pyodbc,
|
||||
sqltypes.Float: _MSFloat_pyodbc,
|
||||
BINARY: _BINARY_pyodbc,
|
||||
# support DateTime(timezone=True)
|
||||
sqltypes.DateTime: _ODBCDateTime,
|
||||
DATETIMEOFFSET: _ODBCDATETIMEOFFSET,
|
||||
# SQL Server dialect has a VARBINARY that is just to support
|
||||
# "deprecate_large_types" w/ VARBINARY(max), but also we must
|
||||
# handle the usual SQL standard VARBINARY
|
||||
VARBINARY: _VARBINARY_pyodbc,
|
||||
sqltypes.VARBINARY: _VARBINARY_pyodbc,
|
||||
sqltypes.LargeBinary: _VARBINARY_pyodbc,
|
||||
},
|
||||
)
|
||||
|
||||
def __init__(
|
||||
self, description_encoding=None, fast_executemany=False, **params
|
||||
):
|
||||
if "description_encoding" in params:
|
||||
self.description_encoding = params.pop("description_encoding")
|
||||
super(MSDialect_pyodbc, self).__init__(**params)
|
||||
self.use_scope_identity = (
|
||||
self.use_scope_identity
|
||||
and self.dbapi
|
||||
and hasattr(self.dbapi.Cursor, "nextset")
|
||||
)
|
||||
self._need_decimal_fix = self.dbapi and self._dbapi_version() < (
|
||||
2,
|
||||
1,
|
||||
8,
|
||||
)
|
||||
self.fast_executemany = fast_executemany
|
||||
|
||||
def _get_server_version_info(self, connection):
|
||||
try:
|
||||
# "Version of the instance of SQL Server, in the form
|
||||
# of 'major.minor.build.revision'"
|
||||
raw = connection.exec_driver_sql(
|
||||
"SELECT CAST(SERVERPROPERTY('ProductVersion') AS VARCHAR)"
|
||||
).scalar()
|
||||
except exc.DBAPIError:
|
||||
# SQL Server docs indicate this function isn't present prior to
|
||||
# 2008. Before we had the VARCHAR cast above, pyodbc would also
|
||||
# fail on this query.
|
||||
return super(MSDialect_pyodbc, self)._get_server_version_info(
|
||||
connection, allow_chars=False
|
||||
)
|
||||
else:
|
||||
version = []
|
||||
r = re.compile(r"[.\-]")
|
||||
for n in r.split(raw):
|
||||
try:
|
||||
version.append(int(n))
|
||||
except ValueError:
|
||||
pass
|
||||
return tuple(version)
|
||||
|
||||
def on_connect(self):
|
||||
super_ = super(MSDialect_pyodbc, self).on_connect()
|
||||
|
||||
def on_connect(conn):
|
||||
if super_ is not None:
|
||||
super_(conn)
|
||||
|
||||
self._setup_timestampoffset_type(conn)
|
||||
|
||||
return on_connect
|
||||
|
||||
def _setup_timestampoffset_type(self, connection):
|
||||
# output converter function for datetimeoffset
|
||||
def _handle_datetimeoffset(dto_value):
|
||||
tup = struct.unpack("<6hI2h", dto_value)
|
||||
return datetime.datetime(
|
||||
tup[0],
|
||||
tup[1],
|
||||
tup[2],
|
||||
tup[3],
|
||||
tup[4],
|
||||
tup[5],
|
||||
tup[6] // 1000,
|
||||
util.timezone(
|
||||
datetime.timedelta(hours=tup[7], minutes=tup[8])
|
||||
),
|
||||
)
|
||||
|
||||
odbc_SQL_SS_TIMESTAMPOFFSET = -155 # as defined in SQLNCLI.h
|
||||
connection.add_output_converter(
|
||||
odbc_SQL_SS_TIMESTAMPOFFSET, _handle_datetimeoffset
|
||||
)
|
||||
|
||||
def do_executemany(self, cursor, statement, parameters, context=None):
|
||||
if self.fast_executemany:
|
||||
cursor.fast_executemany = True
|
||||
super(MSDialect_pyodbc, self).do_executemany(
|
||||
cursor, statement, parameters, context=context
|
||||
)
|
||||
|
||||
def is_disconnect(self, e, connection, cursor):
|
||||
if isinstance(e, self.dbapi.Error):
|
||||
code = e.args[0]
|
||||
if code in {
|
||||
"08S01",
|
||||
"01000",
|
||||
"01002",
|
||||
"08003",
|
||||
"08007",
|
||||
"08S02",
|
||||
"08001",
|
||||
"HYT00",
|
||||
"HY010",
|
||||
"10054",
|
||||
}:
|
||||
return True
|
||||
return super(MSDialect_pyodbc, self).is_disconnect(
|
||||
e, connection, cursor
|
||||
)
|
||||
|
||||
|
||||
dialect = MSDialect_pyodbc
|
||||
Reference in New Issue
Block a user