1743 lines
57 KiB
Python
1743 lines
57 KiB
Python
# types.py
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# Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Michael Bayer mike_mp@zzzcomputing.com
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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: http://www.opensource.org/licenses/mit-license.php
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"""defines genericized SQL types, each represented by a subclass of
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:class:`~sqlalchemy.types.AbstractType`. Dialects define further subclasses of these
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types.
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For more information see the SQLAlchemy documentation on types.
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"""
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__all__ = [ 'TypeEngine', 'TypeDecorator', 'AbstractType', 'UserDefinedType',
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'INT', 'CHAR', 'VARCHAR', 'NCHAR', 'NVARCHAR','TEXT', 'Text',
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'FLOAT', 'NUMERIC', 'DECIMAL', 'TIMESTAMP', 'DATETIME', 'CLOB',
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'BLOB', 'BOOLEAN', 'SMALLINT', 'INTEGER', 'DATE', 'TIME',
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'String', 'Integer', 'SmallInteger', 'BigInteger', 'Numeric',
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'Float', 'DateTime', 'Date', 'Time', 'LargeBinary', 'Binary', 'Boolean',
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'Unicode', 'MutableType', 'Concatenable', 'UnicodeText',
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'PickleType', 'Interval', 'type_map', 'Enum' ]
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import inspect
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import datetime as dt
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from decimal import Decimal as _python_Decimal
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import codecs
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from sqlalchemy import exc, schema
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from sqlalchemy.sql import expression, operators
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import sys
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schema.types = expression.sqltypes =sys.modules['sqlalchemy.types']
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from sqlalchemy.util import pickle
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from sqlalchemy.sql.visitors import Visitable
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from sqlalchemy import util
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from sqlalchemy import processors
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import collections
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NoneType = type(None)
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if util.jython:
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import array
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class AbstractType(Visitable):
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def __init__(self, *args, **kwargs):
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pass
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def compile(self, dialect):
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return dialect.type_compiler.process(self)
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def copy_value(self, value):
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return value
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def bind_processor(self, dialect):
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"""Defines a bind parameter processing function.
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:param dialect: Dialect instance in use.
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"""
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return None
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def result_processor(self, dialect, coltype):
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"""Defines a result-column processing function.
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:param dialect: Dialect instance in use.
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:param coltype: DBAPI coltype argument received in cursor.description.
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"""
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return None
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def compare_values(self, x, y):
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"""Compare two values for equality."""
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return x == y
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def is_mutable(self):
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"""Return True if the target Python type is 'mutable'.
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This allows systems like the ORM to know if a column value can
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be considered 'not changed' by comparing the identity of
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objects alone.
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Use the :class:`MutableType` mixin or override this method to
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return True in custom types that hold mutable values such as
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``dict``, ``list`` and custom objects.
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"""
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return False
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def get_dbapi_type(self, dbapi):
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"""Return the corresponding type object from the underlying DB-API, if
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any.
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This can be useful for calling ``setinputsizes()``, for example.
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"""
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return None
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def _adapt_expression(self, op, othertype):
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"""evaluate the return type of <self> <op> <othertype>,
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and apply any adaptations to the given operator.
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"""
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return op, self
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@util.memoized_property
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def _type_affinity(self):
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"""Return a rudimental 'affinity' value expressing the general class of type."""
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typ = None
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for t in self.__class__.__mro__:
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if t is TypeEngine or t is UserDefinedType:
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return typ
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elif issubclass(t, TypeEngine):
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typ = t
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else:
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return self.__class__
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def _coerce_compared_value(self, op, value):
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_coerced_type = type_map.get(type(value), NULLTYPE)
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if _coerced_type is NULLTYPE or _coerced_type._type_affinity is self._type_affinity:
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return self
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else:
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return _coerced_type
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def _compare_type_affinity(self, other):
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return self._type_affinity is other._type_affinity
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def __repr__(self):
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return "%s(%s)" % (
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self.__class__.__name__,
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", ".join("%s=%r" % (k, getattr(self, k, None))
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for k in inspect.getargspec(self.__init__)[0][1:]))
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class TypeEngine(AbstractType):
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"""Base for built-in types."""
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@util.memoized_property
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def _impl_dict(self):
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return {}
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def dialect_impl(self, dialect, **kwargs):
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key = (dialect.__class__, dialect.server_version_info)
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try:
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return self._impl_dict[key]
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except KeyError:
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return self._impl_dict.setdefault(key, dialect.type_descriptor(self))
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def __getstate__(self):
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d = self.__dict__.copy()
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d.pop('_impl_dict', None)
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return d
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def bind_processor(self, dialect):
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"""Return a conversion function for processing bind values.
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Returns a callable which will receive a bind parameter value
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as the sole positional argument and will return a value to
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send to the DB-API.
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If processing is not necessary, the method should return ``None``.
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"""
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return None
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def result_processor(self, dialect, coltype):
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"""Return a conversion function for processing result row values.
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Returns a callable which will receive a result row column
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value as the sole positional argument and will return a value
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to return to the user.
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If processing is not necessary, the method should return ``None``.
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"""
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return None
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def adapt(self, cls):
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return cls()
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class UserDefinedType(TypeEngine):
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"""Base for user defined types.
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This should be the base of new types. Note that
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for most cases, :class:`TypeDecorator` is probably
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more appropriate::
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import sqlalchemy.types as types
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class MyType(types.UserDefinedType):
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def __init__(self, precision = 8):
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self.precision = precision
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def get_col_spec(self):
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return "MYTYPE(%s)" % self.precision
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def bind_processor(self, dialect):
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def process(value):
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return value
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return process
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def result_processor(self, dialect, coltype):
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def process(value):
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return value
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return process
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Once the type is made, it's immediately usable::
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table = Table('foo', meta,
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Column('id', Integer, primary_key=True),
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Column('data', MyType(16))
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)
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"""
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__visit_name__ = "user_defined"
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def _adapt_expression(self, op, othertype):
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"""evaluate the return type of <self> <op> <othertype>,
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and apply any adaptations to the given operator.
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"""
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return self.adapt_operator(op), self
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def adapt_operator(self, op):
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"""A hook which allows the given operator to be adapted
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to something new.
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See also UserDefinedType._adapt_expression(), an as-yet-
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semi-public method with greater capability in this regard.
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"""
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return op
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class TypeDecorator(AbstractType):
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"""Allows the creation of types which add additional functionality
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to an existing type.
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This method is preferred to direct subclassing of SQLAlchemy's
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built-in types as it ensures that all required functionality of
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the underlying type is kept in place.
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Typical usage::
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import sqlalchemy.types as types
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class MyType(types.TypeDecorator):
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'''Prefixes Unicode values with "PREFIX:" on the way in and
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strips it off on the way out.
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'''
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impl = types.Unicode
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def process_bind_param(self, value, dialect):
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return "PREFIX:" + value
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def process_result_value(self, value, dialect):
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return value[7:]
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def copy(self):
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return MyType(self.impl.length)
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The class-level "impl" variable is required, and can reference any
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TypeEngine class. Alternatively, the load_dialect_impl() method
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can be used to provide different type classes based on the dialect
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given; in this case, the "impl" variable can reference
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``TypeEngine`` as a placeholder.
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Types that receive a Python type that isn't similar to the
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ultimate type used may want to define the :meth:`TypeDecorator.coerce_compared_value`
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method. This is used to give the expression system a hint
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when coercing Python objects into bind parameters within expressions.
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Consider this expression::
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mytable.c.somecol + datetime.date(2009, 5, 15)
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Above, if "somecol" is an ``Integer`` variant, it makes sense that
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we're doing date arithmetic, where above is usually interpreted
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by databases as adding a number of days to the given date.
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The expression system does the right thing by not attempting to
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coerce the "date()" value into an integer-oriented bind parameter.
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However, in the case of ``TypeDecorator``, we are usually changing
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an incoming Python type to something new - ``TypeDecorator`` by
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default will "coerce" the non-typed side to be the same type as itself.
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Such as below, we define an "epoch" type that stores a date value as an integer::
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class MyEpochType(types.TypeDecorator):
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impl = types.Integer
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epoch = datetime.date(1970, 1, 1)
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def process_bind_param(self, value, dialect):
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return (value - self.epoch).days
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def process_result_value(self, value, dialect):
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return self.epoch + timedelta(days=value)
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Our expression of ``somecol + date`` with the above type will coerce the
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"date" on the right side to also be treated as ``MyEpochType``.
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This behavior can be overridden via the :meth:`~TypeDecorator.coerce_compared_value`
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method, which returns a type that should be used for the value of the expression.
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Below we set it such that an integer value will be treated as an ``Integer``,
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and any other value is assumed to be a date and will be treated as a ``MyEpochType``::
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def coerce_compared_value(self, op, value):
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if isinstance(value, int):
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return Integer()
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else:
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return self
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"""
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__visit_name__ = "type_decorator"
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def __init__(self, *args, **kwargs):
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if not hasattr(self.__class__, 'impl'):
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raise AssertionError("TypeDecorator implementations require a class-level "
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"variable 'impl' which refers to the class of type being decorated")
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self.impl = self.__class__.impl(*args, **kwargs)
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def adapt(self, cls):
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return cls()
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def dialect_impl(self, dialect):
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key = (dialect.__class__, dialect.server_version_info)
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try:
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return self._impl_dict[key]
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except KeyError:
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pass
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# adapt the TypeDecorator first, in
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# the case that the dialect maps the TD
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# to one of its native types (i.e. PGInterval)
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adapted = dialect.type_descriptor(self)
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if adapted is not self:
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self._impl_dict[key] = adapted
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return adapted
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# otherwise adapt the impl type, link
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# to a copy of this TypeDecorator and return
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# that.
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typedesc = self.load_dialect_impl(dialect)
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tt = self.copy()
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if not isinstance(tt, self.__class__):
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raise AssertionError("Type object %s does not properly implement the copy() "
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"method, it must return an object of type %s" % (self, self.__class__))
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tt.impl = typedesc
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self._impl_dict[key] = tt
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return tt
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@util.memoized_property
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def _type_affinity(self):
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return self.impl._type_affinity
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def type_engine(self, dialect):
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impl = self.dialect_impl(dialect)
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if not isinstance(impl, TypeDecorator):
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return impl
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else:
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return impl.impl
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def load_dialect_impl(self, dialect):
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"""Loads the dialect-specific implementation of this type.
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by default calls dialect.type_descriptor(self.impl), but
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can be overridden to provide different behavior.
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"""
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if isinstance(self.impl, TypeDecorator):
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return self.impl.dialect_impl(dialect)
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else:
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return dialect.type_descriptor(self.impl)
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def __getattr__(self, key):
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"""Proxy all other undefined accessors to the underlying implementation."""
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return getattr(self.impl, key)
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def process_bind_param(self, value, dialect):
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raise NotImplementedError()
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def process_result_value(self, value, dialect):
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raise NotImplementedError()
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def bind_processor(self, dialect):
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if self.__class__.process_bind_param.func_code is not TypeDecorator.process_bind_param.func_code:
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process_param = self.process_bind_param
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impl_processor = self.impl.bind_processor(dialect)
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if impl_processor:
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def process(value):
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return impl_processor(process_param(value, dialect))
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else:
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def process(value):
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return process_param(value, dialect)
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return process
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else:
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return self.impl.bind_processor(dialect)
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def result_processor(self, dialect, coltype):
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if self.__class__.process_result_value.func_code is not TypeDecorator.process_result_value.func_code:
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process_value = self.process_result_value
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impl_processor = self.impl.result_processor(dialect, coltype)
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if impl_processor:
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def process(value):
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return process_value(impl_processor(value), dialect)
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else:
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def process(value):
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return process_value(value, dialect)
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return process
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else:
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return self.impl.result_processor(dialect, coltype)
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def coerce_compared_value(self, op, value):
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"""Suggest a type for a 'coerced' Python value in an expression.
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By default, returns self. This method is called by
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the expression system when an object using this type is
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on the left or right side of an expression against a plain Python
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object which does not yet have a SQLAlchemy type assigned::
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expr = table.c.somecolumn + 35
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Where above, if ``somecolumn`` uses this type, this method will
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be called with the value ``operator.add``
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and ``35``. The return value is whatever SQLAlchemy type should
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be used for ``35`` for this particular operation.
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"""
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return self
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def _coerce_compared_value(self, op, value):
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return self.coerce_compared_value(op, value)
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def copy(self):
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instance = self.__class__.__new__(self.__class__)
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instance.__dict__.update(self.__dict__)
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instance._impl_dict = {}
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return instance
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def get_dbapi_type(self, dbapi):
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return self.impl.get_dbapi_type(dbapi)
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def copy_value(self, value):
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return self.impl.copy_value(value)
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def compare_values(self, x, y):
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return self.impl.compare_values(x, y)
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def is_mutable(self):
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return self.impl.is_mutable()
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def _adapt_expression(self, op, othertype):
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return self.impl._adapt_expression(op, othertype)
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class MutableType(object):
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"""A mixin that marks a Type as holding a mutable object.
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:meth:`copy_value` and :meth:`compare_values` should be customized
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as needed to match the needs of the object.
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"""
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def is_mutable(self):
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"""Return True, mutable."""
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return True
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def copy_value(self, value):
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"""Unimplemented."""
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raise NotImplementedError()
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def compare_values(self, x, y):
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"""Compare *x* == *y*."""
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return x == y
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def to_instance(typeobj):
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if typeobj is None:
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return NULLTYPE
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if util.callable(typeobj):
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return typeobj()
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else:
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return typeobj
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def adapt_type(typeobj, colspecs):
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if isinstance(typeobj, type):
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typeobj = typeobj()
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for t in typeobj.__class__.__mro__[0:-1]:
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try:
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impltype = colspecs[t]
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break
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except KeyError:
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pass
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else:
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# couldnt adapt - so just return the type itself
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# (it may be a user-defined type)
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return typeobj
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# if we adapted the given generic type to a database-specific type,
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# but it turns out the originally given "generic" type
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# is actually a subclass of our resulting type, then we were already
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# given a more specific type than that required; so use that.
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if (issubclass(typeobj.__class__, impltype)):
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return typeobj
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return typeobj.adapt(impltype)
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class NullType(TypeEngine):
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"""An unknown type.
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NullTypes will stand in if :class:`~sqlalchemy.Table` reflection
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encounters a column data type unknown to SQLAlchemy. The
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resulting columns are nearly fully usable: the DB-API adapter will
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handle all translation to and from the database data type.
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NullType does not have sufficient information to particpate in a
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``CREATE TABLE`` statement and will raise an exception if
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encountered during a :meth:`~sqlalchemy.Table.create` operation.
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"""
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__visit_name__ = 'null'
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def _adapt_expression(self, op, othertype):
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if othertype is NullType or not operators.is_commutative(op):
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return op, self
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else:
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return othertype._adapt_expression(op, self)
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NullTypeEngine = NullType
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class Concatenable(object):
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"""A mixin that marks a type as supporting 'concatenation', typically strings."""
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def _adapt_expression(self, op, othertype):
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if op is operators.add and issubclass(othertype._type_affinity, (Concatenable, NullType)):
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return operators.concat_op, self
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else:
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return op, self
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class _DateAffinity(object):
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"""Mixin date/time specific expression adaptations.
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Rules are implemented within Date,Time,Interval,DateTime, Numeric, Integer.
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Based on http://www.postgresql.org/docs/current/static/functions-datetime.html.
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"""
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@property
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def _expression_adaptations(self):
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raise NotImplementedError()
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|
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_blank_dict = util.frozendict()
|
|
def _adapt_expression(self, op, othertype):
|
|
othertype = othertype._type_affinity
|
|
return op, \
|
|
self._expression_adaptations.get(op, self._blank_dict).\
|
|
get(othertype, NULLTYPE)
|
|
|
|
class String(Concatenable, TypeEngine):
|
|
"""The base for all string and character types.
|
|
|
|
In SQL, corresponds to VARCHAR. Can also take Python unicode objects
|
|
and encode to the database's encoding in bind params (and the reverse for
|
|
result sets.)
|
|
|
|
The `length` field is usually required when the `String` type is
|
|
used within a CREATE TABLE statement, as VARCHAR requires a length
|
|
on most databases.
|
|
|
|
"""
|
|
|
|
__visit_name__ = 'string'
|
|
|
|
def __init__(self, length=None, convert_unicode=False,
|
|
assert_unicode=None, unicode_error=None,
|
|
_warn_on_bytestring=False
|
|
):
|
|
"""
|
|
Create a string-holding type.
|
|
|
|
:param length: optional, a length for the column for use in
|
|
DDL statements. May be safely omitted if no ``CREATE
|
|
TABLE`` will be issued. Certain databases may require a
|
|
*length* for use in DDL, and will raise an exception when
|
|
the ``CREATE TABLE`` DDL is issued. Whether the value is
|
|
interpreted as bytes or characters is database specific.
|
|
|
|
:param convert_unicode: defaults to False. If True, the
|
|
type will do what is necessary in order to accept
|
|
Python Unicode objects as bind parameters, and to return
|
|
Python Unicode objects in result rows. This may
|
|
require SQLAlchemy to explicitly coerce incoming Python
|
|
unicodes into an encoding, and from an encoding
|
|
back to Unicode, or it may not require any interaction
|
|
from SQLAlchemy at all, depending on the DBAPI in use.
|
|
|
|
When SQLAlchemy performs the encoding/decoding,
|
|
the encoding used is configured via
|
|
:attr:`~sqlalchemy.engine.base.Dialect.encoding`, which
|
|
defaults to `utf-8`.
|
|
|
|
The "convert_unicode" behavior can also be turned on
|
|
for all String types by setting
|
|
:attr:`sqlalchemy.engine.base.Dialect.convert_unicode`
|
|
on create_engine().
|
|
|
|
To instruct SQLAlchemy to perform Unicode encoding/decoding
|
|
even on a platform that already handles Unicode natively,
|
|
set convert_unicode='force'. This will incur significant
|
|
performance overhead when fetching unicode result columns.
|
|
|
|
:param assert_unicode: Deprecated. A warning is raised in all cases when a non-Unicode
|
|
object is passed when SQLAlchemy would coerce into an encoding
|
|
(note: but **not** when the DBAPI handles unicode objects natively).
|
|
To suppress or raise this warning to an
|
|
error, use the Python warnings filter documented at:
|
|
http://docs.python.org/library/warnings.html
|
|
|
|
:param unicode_error: Optional, a method to use to handle Unicode
|
|
conversion errors. Behaves like the 'errors' keyword argument to
|
|
the standard library's string.decode() functions. This flag
|
|
requires that `convert_unicode` is set to `"force"` - otherwise,
|
|
SQLAlchemy is not guaranteed to handle the task of unicode
|
|
conversion. Note that this flag adds significant performance
|
|
overhead to row-fetching operations for backends that already
|
|
return unicode objects natively (which most DBAPIs do). This
|
|
flag should only be used as an absolute last resort for reading
|
|
strings from a column with varied or corrupted encodings,
|
|
which only applies to databases that accept invalid encodings
|
|
in the first place (i.e. MySQL. *not* PG, Sqlite, etc.)
|
|
|
|
"""
|
|
if unicode_error is not None and convert_unicode != 'force':
|
|
raise exc.ArgumentError("convert_unicode must be 'force' "
|
|
"when unicode_error is set.")
|
|
|
|
if assert_unicode:
|
|
util.warn_deprecated("assert_unicode is deprecated. "
|
|
"SQLAlchemy emits a warning in all cases where it "
|
|
"would otherwise like to encode a Python unicode object "
|
|
"into a specific encoding but a plain bytestring is received. "
|
|
"This does *not* apply to DBAPIs that coerce Unicode natively."
|
|
)
|
|
self.length = length
|
|
self.convert_unicode = convert_unicode
|
|
self.unicode_error = unicode_error
|
|
self._warn_on_bytestring = _warn_on_bytestring
|
|
|
|
def adapt(self, impltype):
|
|
return impltype(
|
|
length=self.length,
|
|
convert_unicode=self.convert_unicode,
|
|
unicode_error=self.unicode_error,
|
|
_warn_on_bytestring=True,
|
|
)
|
|
|
|
def bind_processor(self, dialect):
|
|
if self.convert_unicode or dialect.convert_unicode:
|
|
if dialect.supports_unicode_binds and self.convert_unicode != 'force':
|
|
if self._warn_on_bytestring:
|
|
def process(value):
|
|
# Py3K
|
|
#if isinstance(value, bytes):
|
|
# Py2K
|
|
if isinstance(value, str):
|
|
# end Py2K
|
|
util.warn("Unicode type received non-unicode bind "
|
|
"param value %r" % value)
|
|
return value
|
|
return process
|
|
else:
|
|
return None
|
|
else:
|
|
encoder = codecs.getencoder(dialect.encoding)
|
|
def process(value):
|
|
if isinstance(value, unicode):
|
|
return encoder(value, self.unicode_error)[0]
|
|
elif value is not None:
|
|
util.warn("Unicode type received non-unicode bind "
|
|
"param value %r" % value)
|
|
return value
|
|
return process
|
|
else:
|
|
return None
|
|
|
|
def result_processor(self, dialect, coltype):
|
|
wants_unicode = self.convert_unicode or dialect.convert_unicode
|
|
needs_convert = wants_unicode and \
|
|
(dialect.returns_unicode_strings is not True or
|
|
self.convert_unicode == 'force')
|
|
|
|
if needs_convert:
|
|
to_unicode = processors.to_unicode_processor_factory(
|
|
dialect.encoding, self.unicode_error)
|
|
|
|
if dialect.returns_unicode_strings:
|
|
# we wouldn't be here unless convert_unicode='force'
|
|
# was specified, or the driver has erratic unicode-returning
|
|
# habits. since we will be getting back unicode
|
|
# in most cases, we check for it (decode will fail).
|
|
def process(value):
|
|
if isinstance(value, unicode):
|
|
return value
|
|
else:
|
|
return to_unicode(value)
|
|
return process
|
|
else:
|
|
# here, we assume that the object is not unicode,
|
|
# avoiding expensive isinstance() check.
|
|
return to_unicode
|
|
else:
|
|
return None
|
|
|
|
def get_dbapi_type(self, dbapi):
|
|
return dbapi.STRING
|
|
|
|
class Text(String):
|
|
"""A variably sized string type.
|
|
|
|
In SQL, usually corresponds to CLOB or TEXT. Can also take Python
|
|
unicode objects and encode to the database's encoding in bind
|
|
params (and the reverse for result sets.)
|
|
|
|
"""
|
|
__visit_name__ = 'text'
|
|
|
|
class Unicode(String):
|
|
"""A variable length Unicode string.
|
|
|
|
The ``Unicode`` type is a :class:`String` which converts Python
|
|
``unicode`` objects (i.e., strings that are defined as
|
|
``u'somevalue'``) into encoded bytestrings when passing the value
|
|
to the database driver, and similarly decodes values from the
|
|
database back into Python ``unicode`` objects.
|
|
|
|
It's roughly equivalent to using a ``String`` object with
|
|
``convert_unicode=True``, however
|
|
the type has other significances in that it implies the usage
|
|
of a unicode-capable type being used on the backend, such as NVARCHAR.
|
|
This may affect what type is emitted when issuing CREATE TABLE
|
|
and also may effect some DBAPI-specific details, such as type
|
|
information passed along to ``setinputsizes()``.
|
|
|
|
When using the ``Unicode`` type, it is only appropriate to pass
|
|
Python ``unicode`` objects, and not plain ``str``. If a
|
|
bytestring (``str``) is passed, a runtime warning is issued. If
|
|
you notice your application raising these warnings but you're not
|
|
sure where, the Python ``warnings`` filter can be used to turn
|
|
these warnings into exceptions which will illustrate a stack
|
|
trace::
|
|
|
|
import warnings
|
|
warnings.simplefilter('error')
|
|
|
|
Bytestrings sent to and received from the database are encoded
|
|
using the dialect's
|
|
:attr:`~sqlalchemy.engine.base.Dialect.encoding`, which defaults
|
|
to `utf-8`.
|
|
|
|
"""
|
|
|
|
__visit_name__ = 'unicode'
|
|
|
|
def __init__(self, length=None, **kwargs):
|
|
"""
|
|
Create a Unicode-converting String type.
|
|
|
|
:param length: optional, a length for the column for use in
|
|
DDL statements. May be safely omitted if no ``CREATE
|
|
TABLE`` will be issued. Certain databases may require a
|
|
*length* for use in DDL, and will raise an exception when
|
|
the ``CREATE TABLE`` DDL is issued. Whether the value is
|
|
interpreted as bytes or characters is database specific.
|
|
|
|
:param \**kwargs: passed through to the underlying ``String``
|
|
type.
|
|
|
|
"""
|
|
kwargs.setdefault('convert_unicode', True)
|
|
kwargs.setdefault('_warn_on_bytestring', True)
|
|
super(Unicode, self).__init__(length=length, **kwargs)
|
|
|
|
class UnicodeText(Text):
|
|
"""An unbounded-length Unicode string.
|
|
|
|
See :class:`Unicode` for details on the unicode
|
|
behavior of this object.
|
|
|
|
Like ``Unicode``, usage the ``UnicodeText`` type implies a
|
|
unicode-capable type being used on the backend, such as NCLOB.
|
|
|
|
"""
|
|
|
|
__visit_name__ = 'unicode_text'
|
|
|
|
def __init__(self, length=None, **kwargs):
|
|
"""
|
|
Create a Unicode-converting Text type.
|
|
|
|
:param length: optional, a length for the column for use in
|
|
DDL statements. May be safely omitted if no ``CREATE
|
|
TABLE`` will be issued. Certain databases may require a
|
|
*length* for use in DDL, and will raise an exception when
|
|
the ``CREATE TABLE`` DDL is issued. Whether the value is
|
|
interpreted as bytes or characters is database specific.
|
|
|
|
"""
|
|
kwargs.setdefault('convert_unicode', True)
|
|
kwargs.setdefault('_warn_on_bytestring', True)
|
|
super(UnicodeText, self).__init__(length=length, **kwargs)
|
|
|
|
|
|
class Integer(_DateAffinity, TypeEngine):
|
|
"""A type for ``int`` integers."""
|
|
|
|
__visit_name__ = 'integer'
|
|
|
|
def get_dbapi_type(self, dbapi):
|
|
return dbapi.NUMBER
|
|
|
|
@util.memoized_property
|
|
def _expression_adaptations(self):
|
|
# TODO: need a dictionary object that will
|
|
# handle operators generically here, this is incomplete
|
|
return {
|
|
operators.add:{
|
|
Date:Date,
|
|
Integer:Integer,
|
|
Numeric:Numeric,
|
|
},
|
|
operators.mul:{
|
|
Interval:Interval,
|
|
Integer:Integer,
|
|
Numeric:Numeric,
|
|
},
|
|
# Py2K
|
|
operators.div:{
|
|
Integer:Integer,
|
|
Numeric:Numeric,
|
|
},
|
|
# end Py2K
|
|
operators.truediv:{
|
|
Integer:Integer,
|
|
Numeric:Numeric,
|
|
},
|
|
operators.sub:{
|
|
Integer:Integer,
|
|
Numeric:Numeric,
|
|
},
|
|
}
|
|
|
|
class SmallInteger(Integer):
|
|
"""A type for smaller ``int`` integers.
|
|
|
|
Typically generates a ``SMALLINT`` in DDL, and otherwise acts like
|
|
a normal :class:`Integer` on the Python side.
|
|
|
|
"""
|
|
|
|
__visit_name__ = 'small_integer'
|
|
|
|
class BigInteger(Integer):
|
|
"""A type for bigger ``int`` integers.
|
|
|
|
Typically generates a ``BIGINT`` in DDL, and otherwise acts like
|
|
a normal :class:`Integer` on the Python side.
|
|
|
|
"""
|
|
|
|
__visit_name__ = 'big_integer'
|
|
|
|
class Numeric(_DateAffinity, TypeEngine):
|
|
"""A type for fixed precision numbers.
|
|
|
|
Typically generates DECIMAL or NUMERIC. Returns
|
|
``decimal.Decimal`` objects by default, applying
|
|
conversion as needed.
|
|
|
|
"""
|
|
|
|
__visit_name__ = 'numeric'
|
|
|
|
def __init__(self, precision=None, scale=None, asdecimal=True):
|
|
"""
|
|
Construct a Numeric.
|
|
|
|
:param precision: the numeric precision for use in DDL ``CREATE TABLE``.
|
|
|
|
:param scale: the numeric scale for use in DDL ``CREATE TABLE``.
|
|
|
|
:param asdecimal: default True. Return whether or not
|
|
values should be sent as Python Decimal objects, or
|
|
as floats. Different DBAPIs send one or the other based on
|
|
datatypes - the Numeric type will ensure that return values
|
|
are one or the other across DBAPIs consistently.
|
|
|
|
When using the ``Numeric`` type, care should be taken to ensure
|
|
that the asdecimal setting is apppropriate for the DBAPI in use -
|
|
when Numeric applies a conversion from Decimal->float or float->
|
|
Decimal, this conversion incurs an additional performance overhead
|
|
for all result columns received.
|
|
|
|
DBAPIs that return Decimal natively (e.g. psycopg2) will have
|
|
better accuracy and higher performance with a setting of ``True``,
|
|
as the native translation to Decimal reduces the amount of floating-
|
|
point issues at play, and the Numeric type itself doesn't need
|
|
to apply any further conversions. However, another DBAPI which
|
|
returns floats natively *will* incur an additional conversion
|
|
overhead, and is still subject to floating point data loss - in
|
|
which case ``asdecimal=False`` will at least remove the extra
|
|
conversion overhead.
|
|
|
|
"""
|
|
self.precision = precision
|
|
self.scale = scale
|
|
self.asdecimal = asdecimal
|
|
|
|
def adapt(self, impltype):
|
|
return impltype(
|
|
precision=self.precision,
|
|
scale=self.scale,
|
|
asdecimal=self.asdecimal)
|
|
|
|
def get_dbapi_type(self, dbapi):
|
|
return dbapi.NUMBER
|
|
|
|
def bind_processor(self, dialect):
|
|
if dialect.supports_native_decimal:
|
|
return None
|
|
else:
|
|
return processors.to_float
|
|
|
|
def result_processor(self, dialect, coltype):
|
|
if self.asdecimal:
|
|
if dialect.supports_native_decimal:
|
|
# we're a "numeric", DBAPI will give us Decimal directly
|
|
return None
|
|
else:
|
|
# we're a "numeric", DBAPI returns floats, convert.
|
|
if self.scale is not None:
|
|
return processors.to_decimal_processor_factory(_python_Decimal, self.scale)
|
|
else:
|
|
return processors.to_decimal_processor_factory(_python_Decimal)
|
|
else:
|
|
if dialect.supports_native_decimal:
|
|
return processors.to_float
|
|
else:
|
|
return None
|
|
|
|
@util.memoized_property
|
|
def _expression_adaptations(self):
|
|
return {
|
|
operators.mul:{
|
|
Interval:Interval
|
|
},
|
|
}
|
|
|
|
|
|
class Float(Numeric):
|
|
"""A type for ``float`` numbers.
|
|
|
|
Returns Python ``float`` objects by default, applying
|
|
conversion as needed.
|
|
|
|
"""
|
|
|
|
__visit_name__ = 'float'
|
|
|
|
def __init__(self, precision=None, asdecimal=False, **kwargs):
|
|
"""
|
|
Construct a Float.
|
|
|
|
:param precision: the numeric precision for use in DDL ``CREATE TABLE``.
|
|
|
|
:param asdecimal: the same flag as that of :class:`Numeric`, but
|
|
defaults to ``False``.
|
|
|
|
"""
|
|
self.precision = precision
|
|
self.asdecimal = asdecimal
|
|
|
|
def adapt(self, impltype):
|
|
return impltype(precision=self.precision, asdecimal=self.asdecimal)
|
|
|
|
def result_processor(self, dialect, coltype):
|
|
if self.asdecimal:
|
|
return processors.to_decimal_processor_factory(_python_Decimal)
|
|
else:
|
|
return None
|
|
|
|
|
|
class DateTime(_DateAffinity, TypeEngine):
|
|
"""A type for ``datetime.datetime()`` objects.
|
|
|
|
Date and time types return objects from the Python ``datetime``
|
|
module. Most DBAPIs have built in support for the datetime
|
|
module, with the noted exception of SQLite. In the case of
|
|
SQLite, date and time types are stored as strings which are then
|
|
converted back to datetime objects when rows are returned.
|
|
|
|
"""
|
|
|
|
__visit_name__ = 'datetime'
|
|
|
|
def __init__(self, timezone=False):
|
|
self.timezone = timezone
|
|
|
|
def adapt(self, impltype):
|
|
return impltype(timezone=self.timezone)
|
|
|
|
def get_dbapi_type(self, dbapi):
|
|
return dbapi.DATETIME
|
|
|
|
@util.memoized_property
|
|
def _expression_adaptations(self):
|
|
return {
|
|
operators.add:{
|
|
Interval:DateTime,
|
|
},
|
|
operators.sub:{
|
|
Interval:DateTime,
|
|
DateTime:Interval,
|
|
},
|
|
}
|
|
|
|
|
|
class Date(_DateAffinity,TypeEngine):
|
|
"""A type for ``datetime.date()`` objects."""
|
|
|
|
__visit_name__ = 'date'
|
|
|
|
def get_dbapi_type(self, dbapi):
|
|
return dbapi.DATETIME
|
|
|
|
@util.memoized_property
|
|
def _expression_adaptations(self):
|
|
return {
|
|
operators.add:{
|
|
Integer:Date,
|
|
Interval:DateTime,
|
|
Time:DateTime,
|
|
},
|
|
operators.sub:{
|
|
# date - integer = date
|
|
Integer:Date,
|
|
|
|
# date - date = integer.
|
|
Date:Integer,
|
|
|
|
Interval:DateTime,
|
|
|
|
# date - datetime = interval,
|
|
# this one is not in the PG docs
|
|
# but works
|
|
DateTime:Interval,
|
|
},
|
|
}
|
|
|
|
|
|
class Time(_DateAffinity,TypeEngine):
|
|
"""A type for ``datetime.time()`` objects."""
|
|
|
|
__visit_name__ = 'time'
|
|
|
|
def __init__(self, timezone=False):
|
|
self.timezone = timezone
|
|
|
|
def adapt(self, impltype):
|
|
return impltype(timezone=self.timezone)
|
|
|
|
def get_dbapi_type(self, dbapi):
|
|
return dbapi.DATETIME
|
|
|
|
@util.memoized_property
|
|
def _expression_adaptations(self):
|
|
return {
|
|
operators.add:{
|
|
Date:DateTime,
|
|
Interval:Time
|
|
},
|
|
operators.sub:{
|
|
Time:Interval,
|
|
Interval:Time,
|
|
},
|
|
}
|
|
|
|
|
|
class _Binary(TypeEngine):
|
|
"""Define base behavior for binary types."""
|
|
|
|
def __init__(self, length=None):
|
|
self.length = length
|
|
|
|
# Python 3 - sqlite3 doesn't need the `Binary` conversion
|
|
# here, though pg8000 does to indicate "bytea"
|
|
def bind_processor(self, dialect):
|
|
DBAPIBinary = dialect.dbapi.Binary
|
|
def process(value):
|
|
if value is not None:
|
|
return DBAPIBinary(value)
|
|
else:
|
|
return None
|
|
return process
|
|
|
|
# Python 3 has native bytes() type
|
|
# both sqlite3 and pg8000 seem to return it
|
|
# (i.e. and not 'memoryview')
|
|
# Py2K
|
|
def result_processor(self, dialect, coltype):
|
|
if util.jython:
|
|
def process(value):
|
|
if value is not None:
|
|
if isinstance(value, array.array):
|
|
return value.tostring()
|
|
return str(value)
|
|
else:
|
|
return None
|
|
else:
|
|
process = processors.to_str
|
|
return process
|
|
# end Py2K
|
|
|
|
def adapt(self, impltype):
|
|
return impltype(length=self.length)
|
|
|
|
def get_dbapi_type(self, dbapi):
|
|
return dbapi.BINARY
|
|
|
|
class LargeBinary(_Binary):
|
|
"""A type for large binary byte data.
|
|
|
|
The Binary type generates BLOB or BYTEA when tables are created,
|
|
and also converts incoming values using the ``Binary`` callable
|
|
provided by each DB-API.
|
|
|
|
"""
|
|
|
|
__visit_name__ = 'large_binary'
|
|
|
|
def __init__(self, length=None):
|
|
"""
|
|
Construct a LargeBinary type.
|
|
|
|
:param length: optional, a length for the column for use in
|
|
DDL statements, for those BLOB types that accept a length
|
|
(i.e. MySQL). It does *not* produce a small BINARY/VARBINARY
|
|
type - use the BINARY/VARBINARY types specifically for those.
|
|
May be safely omitted if no ``CREATE
|
|
TABLE`` will be issued. Certain databases may require a
|
|
*length* for use in DDL, and will raise an exception when
|
|
the ``CREATE TABLE`` DDL is issued.
|
|
|
|
"""
|
|
_Binary.__init__(self, length=length)
|
|
|
|
class Binary(LargeBinary):
|
|
"""Deprecated. Renamed to LargeBinary."""
|
|
|
|
def __init__(self, *arg, **kw):
|
|
util.warn_deprecated("The Binary type has been renamed to LargeBinary.")
|
|
LargeBinary.__init__(self, *arg, **kw)
|
|
|
|
class SchemaType(object):
|
|
"""Mark a type as possibly requiring schema-level DDL for usage.
|
|
|
|
Supports types that must be explicitly created/dropped (i.e. PG ENUM type)
|
|
as well as types that are complimented by table or schema level
|
|
constraints, triggers, and other rules.
|
|
|
|
"""
|
|
|
|
def __init__(self, **kw):
|
|
self.name = kw.pop('name', None)
|
|
self.quote = kw.pop('quote', None)
|
|
self.schema = kw.pop('schema', None)
|
|
self.metadata = kw.pop('metadata', None)
|
|
if self.metadata:
|
|
self.metadata.append_ddl_listener(
|
|
'before-create',
|
|
util.portable_instancemethod(self._on_metadata_create)
|
|
)
|
|
self.metadata.append_ddl_listener(
|
|
'after-drop',
|
|
util.portable_instancemethod(self._on_metadata_drop)
|
|
)
|
|
|
|
def _set_parent(self, column):
|
|
column._on_table_attach(util.portable_instancemethod(self._set_table))
|
|
|
|
def _set_table(self, table, column):
|
|
table.append_ddl_listener(
|
|
'before-create',
|
|
util.portable_instancemethod(self._on_table_create)
|
|
)
|
|
table.append_ddl_listener(
|
|
'after-drop',
|
|
util.portable_instancemethod(self._on_table_drop)
|
|
)
|
|
if self.metadata is None:
|
|
table.metadata.append_ddl_listener(
|
|
'before-create',
|
|
util.portable_instancemethod(self._on_metadata_create)
|
|
)
|
|
table.metadata.append_ddl_listener(
|
|
'after-drop',
|
|
util.portable_instancemethod(self._on_metadata_drop)
|
|
)
|
|
|
|
@property
|
|
def bind(self):
|
|
return self.metadata and self.metadata.bind or None
|
|
|
|
def create(self, bind=None, checkfirst=False):
|
|
"""Issue CREATE ddl for this type, if applicable."""
|
|
|
|
from sqlalchemy.schema import _bind_or_error
|
|
if bind is None:
|
|
bind = _bind_or_error(self)
|
|
t = self.dialect_impl(bind.dialect)
|
|
if t is not self and isinstance(t, SchemaType):
|
|
t.create(bind=bind, checkfirst=checkfirst)
|
|
|
|
def drop(self, bind=None, checkfirst=False):
|
|
"""Issue DROP ddl for this type, if applicable."""
|
|
|
|
from sqlalchemy.schema import _bind_or_error
|
|
if bind is None:
|
|
bind = _bind_or_error(self)
|
|
t = self.dialect_impl(bind.dialect)
|
|
if t is not self and isinstance(t, SchemaType):
|
|
t.drop(bind=bind, checkfirst=checkfirst)
|
|
|
|
def _on_table_create(self, event, target, bind, **kw):
|
|
t = self.dialect_impl(bind.dialect)
|
|
if t is not self and isinstance(t, SchemaType):
|
|
t._on_table_create(event, target, bind, **kw)
|
|
|
|
def _on_table_drop(self, event, target, bind, **kw):
|
|
t = self.dialect_impl(bind.dialect)
|
|
if t is not self and isinstance(t, SchemaType):
|
|
t._on_table_drop(event, target, bind, **kw)
|
|
|
|
def _on_metadata_create(self, event, target, bind, **kw):
|
|
t = self.dialect_impl(bind.dialect)
|
|
if t is not self and isinstance(t, SchemaType):
|
|
t._on_metadata_create(event, target, bind, **kw)
|
|
|
|
def _on_metadata_drop(self, event, target, bind, **kw):
|
|
t = self.dialect_impl(bind.dialect)
|
|
if t is not self and isinstance(t, SchemaType):
|
|
t._on_metadata_drop(event, target, bind, **kw)
|
|
|
|
class Enum(String, SchemaType):
|
|
"""Generic Enum Type.
|
|
|
|
The Enum type provides a set of possible string values which the
|
|
column is constrained towards.
|
|
|
|
By default, uses the backend's native ENUM type if available,
|
|
else uses VARCHAR + a CHECK constraint.
|
|
"""
|
|
|
|
__visit_name__ = 'enum'
|
|
|
|
def __init__(self, *enums, **kw):
|
|
"""Construct an enum.
|
|
|
|
Keyword arguments which don't apply to a specific backend are ignored
|
|
by that backend.
|
|
|
|
:param \*enums: string or unicode enumeration labels. If unicode labels
|
|
are present, the `convert_unicode` flag is auto-enabled.
|
|
|
|
:param convert_unicode: Enable unicode-aware bind parameter and result-set
|
|
processing for this Enum's data. This is set automatically based on
|
|
the presence of unicode label strings.
|
|
|
|
:param metadata: Associate this type directly with a ``MetaData`` object.
|
|
For types that exist on the target database as an independent schema
|
|
construct (Postgresql), this type will be created and dropped within
|
|
``create_all()`` and ``drop_all()`` operations. If the type is not
|
|
associated with any ``MetaData`` object, it will associate itself with
|
|
each ``Table`` in which it is used, and will be created when any of
|
|
those individual tables are created, after a check is performed for
|
|
it's existence. The type is only dropped when ``drop_all()`` is called
|
|
for that ``Table`` object's metadata, however.
|
|
|
|
:param name: The name of this type. This is required for Postgresql and
|
|
any future supported database which requires an explicitly named type,
|
|
or an explicitly named constraint in order to generate the type and/or
|
|
a table that uses it.
|
|
|
|
:param native_enum: Use the database's native ENUM type when available.
|
|
Defaults to True. When False, uses VARCHAR + check constraint
|
|
for all backends.
|
|
|
|
:param schema: Schemaname of this type. For types that exist on the target
|
|
database as an independent schema construct (Postgresql), this
|
|
parameter specifies the named schema in which the type is present.
|
|
|
|
:param quote: Force quoting to be on or off on the type's name. If left as
|
|
the default of `None`, the usual schema-level "case
|
|
sensitive"/"reserved name" rules are used to determine if this type's
|
|
name should be quoted.
|
|
|
|
"""
|
|
self.enums = enums
|
|
self.native_enum = kw.pop('native_enum', True)
|
|
convert_unicode= kw.pop('convert_unicode', None)
|
|
if convert_unicode is None:
|
|
for e in enums:
|
|
if isinstance(e, unicode):
|
|
convert_unicode = True
|
|
break
|
|
else:
|
|
convert_unicode = False
|
|
|
|
if self.enums:
|
|
length =max(len(x) for x in self.enums)
|
|
else:
|
|
length = 0
|
|
String.__init__(self,
|
|
length =length,
|
|
convert_unicode=convert_unicode,
|
|
)
|
|
SchemaType.__init__(self, **kw)
|
|
|
|
def _should_create_constraint(self, compiler):
|
|
return not self.native_enum or \
|
|
not compiler.dialect.supports_native_enum
|
|
|
|
def _set_table(self, table, column):
|
|
if self.native_enum:
|
|
SchemaType._set_table(self, table, column)
|
|
|
|
|
|
e = schema.CheckConstraint(
|
|
column.in_(self.enums),
|
|
name=self.name,
|
|
_create_rule=util.portable_instancemethod(self._should_create_constraint)
|
|
)
|
|
table.append_constraint(e)
|
|
|
|
def adapt(self, impltype):
|
|
if issubclass(impltype, Enum):
|
|
return impltype(name=self.name,
|
|
quote=self.quote,
|
|
schema=self.schema,
|
|
metadata=self.metadata,
|
|
convert_unicode=self.convert_unicode,
|
|
*self.enums
|
|
)
|
|
else:
|
|
return super(Enum, self).adapt(impltype)
|
|
|
|
class PickleType(MutableType, TypeDecorator):
|
|
"""Holds Python objects.
|
|
|
|
PickleType builds upon the Binary type to apply Python's
|
|
``pickle.dumps()`` to incoming objects, and ``pickle.loads()`` on
|
|
the way out, allowing any pickleable Python object to be stored as
|
|
a serialized binary field.
|
|
|
|
"""
|
|
|
|
impl = LargeBinary
|
|
|
|
def __init__(self, protocol=pickle.HIGHEST_PROTOCOL, pickler=None, mutable=True, comparator=None):
|
|
"""
|
|
Construct a PickleType.
|
|
|
|
:param protocol: defaults to ``pickle.HIGHEST_PROTOCOL``.
|
|
|
|
:param pickler: defaults to cPickle.pickle or pickle.pickle if
|
|
cPickle is not available. May be any object with
|
|
pickle-compatible ``dumps` and ``loads`` methods.
|
|
|
|
:param mutable: defaults to True; implements
|
|
:meth:`AbstractType.is_mutable`. When ``True``, incoming
|
|
objects should provide an ``__eq__()`` method which
|
|
performs the desired deep comparison of members, or the
|
|
``comparator`` argument must be present.
|
|
|
|
:param comparator: optional. a 2-arg callable predicate used
|
|
to compare values of this type. Otherwise,
|
|
the == operator is used to compare values.
|
|
|
|
"""
|
|
self.protocol = protocol
|
|
self.pickler = pickler or pickle
|
|
self.mutable = mutable
|
|
self.comparator = comparator
|
|
super(PickleType, self).__init__()
|
|
|
|
def bind_processor(self, dialect):
|
|
impl_processor = self.impl.bind_processor(dialect)
|
|
dumps = self.pickler.dumps
|
|
protocol = self.protocol
|
|
if impl_processor:
|
|
def process(value):
|
|
if value is not None:
|
|
value = dumps(value, protocol)
|
|
return impl_processor(value)
|
|
else:
|
|
def process(value):
|
|
if value is not None:
|
|
value = dumps(value, protocol)
|
|
return value
|
|
return process
|
|
|
|
def result_processor(self, dialect, coltype):
|
|
impl_processor = self.impl.result_processor(dialect, coltype)
|
|
loads = self.pickler.loads
|
|
if impl_processor:
|
|
def process(value):
|
|
value = impl_processor(value)
|
|
if value is None:
|
|
return None
|
|
return loads(value)
|
|
else:
|
|
def process(value):
|
|
if value is None:
|
|
return None
|
|
return loads(value)
|
|
return process
|
|
|
|
def copy_value(self, value):
|
|
if self.mutable:
|
|
return self.pickler.loads(self.pickler.dumps(value, self.protocol))
|
|
else:
|
|
return value
|
|
|
|
def compare_values(self, x, y):
|
|
if self.comparator:
|
|
return self.comparator(x, y)
|
|
else:
|
|
return x == y
|
|
|
|
def is_mutable(self):
|
|
return self.mutable
|
|
|
|
|
|
class Boolean(TypeEngine, SchemaType):
|
|
"""A bool datatype.
|
|
|
|
Boolean typically uses BOOLEAN or SMALLINT on the DDL side, and on
|
|
the Python side deals in ``True`` or ``False``.
|
|
|
|
"""
|
|
|
|
__visit_name__ = 'boolean'
|
|
|
|
def __init__(self, create_constraint=True, name=None):
|
|
"""Construct a Boolean.
|
|
|
|
:param create_constraint: defaults to True. If the boolean
|
|
is generated as an int/smallint, also create a CHECK constraint
|
|
on the table that ensures 1 or 0 as a value.
|
|
|
|
:param name: if a CHECK constraint is generated, specify
|
|
the name of the constraint.
|
|
|
|
"""
|
|
self.create_constraint = create_constraint
|
|
self.name = name
|
|
|
|
def _should_create_constraint(self, compiler):
|
|
return not compiler.dialect.supports_native_boolean
|
|
|
|
def _set_table(self, table, column):
|
|
if not self.create_constraint:
|
|
return
|
|
|
|
e = schema.CheckConstraint(
|
|
column.in_([0, 1]),
|
|
name=self.name,
|
|
_create_rule=util.portable_instancemethod(self._should_create_constraint)
|
|
)
|
|
table.append_constraint(e)
|
|
|
|
def result_processor(self, dialect, coltype):
|
|
if dialect.supports_native_boolean:
|
|
return None
|
|
else:
|
|
return processors.int_to_boolean
|
|
|
|
class Interval(_DateAffinity, TypeDecorator):
|
|
"""A type for ``datetime.timedelta()`` objects.
|
|
|
|
The Interval type deals with ``datetime.timedelta`` objects. In
|
|
PostgreSQL, the native ``INTERVAL`` type is used; for others, the
|
|
value is stored as a date which is relative to the "epoch"
|
|
(Jan. 1, 1970).
|
|
|
|
Note that the ``Interval`` type does not currently provide
|
|
date arithmetic operations on platforms which do not support
|
|
interval types natively. Such operations usually require
|
|
transformation of both sides of the expression (such as, conversion
|
|
of both sides into integer epoch values first) which currently
|
|
is a manual procedure (such as via :attr:`~sqlalchemy.sql.expression.func`).
|
|
|
|
"""
|
|
|
|
impl = DateTime
|
|
epoch = dt.datetime.utcfromtimestamp(0)
|
|
|
|
def __init__(self, native=True,
|
|
second_precision=None,
|
|
day_precision=None):
|
|
"""Construct an Interval object.
|
|
|
|
:param native: when True, use the actual
|
|
INTERVAL type provided by the database, if
|
|
supported (currently Postgresql, Oracle).
|
|
Otherwise, represent the interval data as
|
|
an epoch value regardless.
|
|
|
|
:param second_precision: For native interval types
|
|
which support a "fractional seconds precision" parameter,
|
|
i.e. Oracle and Postgresql
|
|
|
|
:param day_precision: for native interval types which
|
|
support a "day precision" parameter, i.e. Oracle.
|
|
|
|
"""
|
|
super(Interval, self).__init__()
|
|
self.native = native
|
|
self.second_precision = second_precision
|
|
self.day_precision = day_precision
|
|
|
|
def adapt(self, cls):
|
|
if self.native:
|
|
return cls._adapt_from_generic_interval(self)
|
|
else:
|
|
return self
|
|
|
|
def bind_processor(self, dialect):
|
|
impl_processor = self.impl.bind_processor(dialect)
|
|
epoch = self.epoch
|
|
if impl_processor:
|
|
def process(value):
|
|
if value is not None:
|
|
value = epoch + value
|
|
return impl_processor(value)
|
|
else:
|
|
def process(value):
|
|
if value is not None:
|
|
value = epoch + value
|
|
return value
|
|
return process
|
|
|
|
def result_processor(self, dialect, coltype):
|
|
impl_processor = self.impl.result_processor(dialect, coltype)
|
|
epoch = self.epoch
|
|
if impl_processor:
|
|
def process(value):
|
|
value = impl_processor(value)
|
|
if value is None:
|
|
return None
|
|
return value - epoch
|
|
else:
|
|
def process(value):
|
|
if value is None:
|
|
return None
|
|
return value - epoch
|
|
return process
|
|
|
|
@util.memoized_property
|
|
def _expression_adaptations(self):
|
|
return {
|
|
operators.add:{
|
|
Date:DateTime,
|
|
Interval:Interval,
|
|
DateTime:DateTime,
|
|
Time:Time,
|
|
},
|
|
operators.sub:{
|
|
Interval:Interval
|
|
},
|
|
operators.mul:{
|
|
Numeric:Interval
|
|
},
|
|
operators.truediv: {
|
|
Numeric:Interval
|
|
},
|
|
# Py2K
|
|
operators.div: {
|
|
Numeric:Interval
|
|
}
|
|
# end Py2K
|
|
}
|
|
|
|
@property
|
|
def _type_affinity(self):
|
|
return Interval
|
|
|
|
def _coerce_compared_value(self, op, value):
|
|
return self.impl._coerce_compared_value(op, value)
|
|
|
|
|
|
class FLOAT(Float):
|
|
"""The SQL FLOAT type."""
|
|
|
|
__visit_name__ = 'FLOAT'
|
|
|
|
class NUMERIC(Numeric):
|
|
"""The SQL NUMERIC type."""
|
|
|
|
__visit_name__ = 'NUMERIC'
|
|
|
|
|
|
class DECIMAL(Numeric):
|
|
"""The SQL DECIMAL type."""
|
|
|
|
__visit_name__ = 'DECIMAL'
|
|
|
|
|
|
class INTEGER(Integer):
|
|
"""The SQL INT or INTEGER type."""
|
|
|
|
__visit_name__ = 'INTEGER'
|
|
INT = INTEGER
|
|
|
|
|
|
class SMALLINT(SmallInteger):
|
|
"""The SQL SMALLINT type."""
|
|
|
|
__visit_name__ = 'SMALLINT'
|
|
|
|
|
|
class BIGINT(BigInteger):
|
|
"""The SQL BIGINT type."""
|
|
|
|
__visit_name__ = 'BIGINT'
|
|
|
|
class TIMESTAMP(DateTime):
|
|
"""The SQL TIMESTAMP type."""
|
|
|
|
__visit_name__ = 'TIMESTAMP'
|
|
|
|
def get_dbapi_type(self, dbapi):
|
|
return dbapi.TIMESTAMP
|
|
|
|
class DATETIME(DateTime):
|
|
"""The SQL DATETIME type."""
|
|
|
|
__visit_name__ = 'DATETIME'
|
|
|
|
|
|
class DATE(Date):
|
|
"""The SQL DATE type."""
|
|
|
|
__visit_name__ = 'DATE'
|
|
|
|
|
|
class TIME(Time):
|
|
"""The SQL TIME type."""
|
|
|
|
__visit_name__ = 'TIME'
|
|
|
|
class TEXT(Text):
|
|
"""The SQL TEXT type."""
|
|
|
|
__visit_name__ = 'TEXT'
|
|
|
|
class CLOB(Text):
|
|
"""The CLOB type.
|
|
|
|
This type is found in Oracle and Informix.
|
|
"""
|
|
|
|
__visit_name__ = 'CLOB'
|
|
|
|
class VARCHAR(String):
|
|
"""The SQL VARCHAR type."""
|
|
|
|
__visit_name__ = 'VARCHAR'
|
|
|
|
class NVARCHAR(Unicode):
|
|
"""The SQL NVARCHAR type."""
|
|
|
|
__visit_name__ = 'NVARCHAR'
|
|
|
|
class CHAR(String):
|
|
"""The SQL CHAR type."""
|
|
|
|
__visit_name__ = 'CHAR'
|
|
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class NCHAR(Unicode):
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"""The SQL NCHAR type."""
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__visit_name__ = 'NCHAR'
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class BLOB(LargeBinary):
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"""The SQL BLOB type."""
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__visit_name__ = 'BLOB'
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class BINARY(_Binary):
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"""The SQL BINARY type."""
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__visit_name__ = 'BINARY'
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class VARBINARY(_Binary):
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"""The SQL VARBINARY type."""
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__visit_name__ = 'VARBINARY'
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class BOOLEAN(Boolean):
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"""The SQL BOOLEAN type."""
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__visit_name__ = 'BOOLEAN'
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NULLTYPE = NullType()
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BOOLEANTYPE = Boolean()
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|
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# using VARCHAR/NCHAR so that we dont get the genericized "String"
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|
# type which usually resolves to TEXT/CLOB
|
|
type_map = {
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|
str: String(),
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# Py3K
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#bytes : LargeBinary(),
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|
# Py2K
|
|
unicode : Unicode(),
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|
# end Py2K
|
|
int : Integer(),
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|
float : Numeric(),
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|
bool: BOOLEANTYPE,
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|
_python_Decimal : Numeric(),
|
|
dt.date : Date(),
|
|
dt.datetime : DateTime(),
|
|
dt.time : Time(),
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|
dt.timedelta : Interval(),
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NoneType: NULLTYPE
|
|
}
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