sqlalchemy.types.DateTime

class documentation

class DateTime(_LookupExpressionAdapter, TypeEngine):

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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.

For the time representation within the datetime type, some backends include additional options, such as timezone support and fractional seconds support. For fractional seconds, use the dialect-specific datatype, such as .mysql.TIME. For timezone support, use at least the _types.TIMESTAMP datatype, if not the dialect-specific datatype object.

Method	`__init__`	Construct a new `.DateTime`.
Method	`get_dbapi_type`	Return the corresponding type object from the underlying DB-API, if any.
Method	`_resolve_for_literal`	adjust this type given a literal Python value that will be stored in a bound parameter.
Class Variable	`__visit_name__`	Undocumented
Instance Variable	`timezone`	Undocumented
Property	`_expression_adaptations`	Undocumented
Property	`python_type`	Return the Python type object expected to be returned by instances of this type, if known.

Inherited from _LookupExpressionAdapter:

Class Comparator Undocumented

Inherited from TypeEngine:

Class	`Comparator`	Base class for custom comparison operations defined at the type level. See `.TypeEngine.comparator_factory`.
Method	`adapt`	Produce an "adapted" form of this type, given an "impl" class to work with.
Method	`as_generic`	Return an instance of the generic type corresponding to this type using heuristic rule. The method may be overridden if this heuristic rule is not sufficient.
Method	`bind_expression`	Given a bind value (i.e. a `.BindParameter` instance), return a SQL expression in its place.
Method	`bind_processor`	Return a conversion function for processing bind values.
Method	`coerce_compared_value`	Suggest a type for a 'coerced' Python value in an expression.
Method	`column_expression`	Given a SELECT column expression, return a wrapping SQL expression.
Method	`compare_against_backend`	Compare this type against the given backend type.
Method	`compare_values`	Compare two values for equality.
Method	`compile`	Produce a string-compiled form of this `.TypeEngine`.
Method	`dialect_impl`	Return a dialect-specific implementation for this `.TypeEngine`.
Method	`evaluates_none`	Return a copy of this type which has the `.should_evaluate_none` flag set to True.
Method	`literal_processor`	Return a conversion function for processing literal values that are to be rendered directly without using binds.
Method	`result_processor`	Return a conversion function for processing result row values.
Method	`with_variant`	Produce a new type object that will utilize the given type when applied to the dialect of the given name.
Class Variable	`hashable`	Flag, if False, means values from this type aren't hashable.
Class Variable	`should_evaluate_none`	If True, the Python constant `None` is considered to be handled explicitly by this type.
Class Variable	`sort_key_function`	A sorting function that can be passed as the key to sorted.
Static Method	`_to_instance`	Undocumented
Method	`__repr__`	Undocumented
Method	`__str__`	Undocumented
Method	`_cached_bind_processor`	Return a dialect-specific bind processor for this type.
Method	`_cached_custom_processor`	Undocumented
Method	`_cached_literal_processor`	Return a dialect-specific literal processor for this type.
Method	`_cached_result_processor`	Return a dialect-specific result processor for this type.
Method	`_compare_type_affinity`	Undocumented
Method	`_default_dialect`	Undocumented
Method	`_dialect_info`	Return a dialect-specific registry which caches a dialect-specific implementation, bind processing function, and one or more result processing functions.
Method	`_gen_dialect_impl`	Undocumented
Method	`_unwrapped_dialect_impl`	Return the 'unwrapped' dialect impl for this type.
Method	`copy`	Undocumented
Method	`copy_value`	Undocumented
Class Variable	`_is_array`	Undocumented
Class Variable	`_is_table_value`	Undocumented
Class Variable	`_is_tuple_type`	Undocumented
Class Variable	`_is_type_decorator`	Undocumented
Class Variable	`_isnull`	Undocumented
Class Variable	`_sqla_type`	Undocumented
Property	`_generic_type_affinity`	Undocumented
Property	`_has_bind_expression`	memoized boolean, check if bind_expression is implemented.
Property	`_has_column_expression`	memoized boolean, check if column_expression is implemented.
Property	`_static_cache_key`	Undocumented
Property	`_type_affinity`	Return a rudimental 'affinity' value expressing the general class of type.

Inherited from Traversible (via TypeEngine):

Method	`get_children`	Return immediate child `.visitors.Traversible` elements of this `.visitors.Traversible`.
Method	`__class_getitem__`	Undocumented

def __init__(self, timezone=False):

overridden in sqlalchemy.dialects.mssql.DATETIME2, sqlalchemy.dialects.mssql.DATETIMEOFFSET, sqlalchemy.dialects.mysql.types.DATETIME, sqlalchemy.dialects.sqlite.DATETIME, sqlalchemy.types.TIMESTAMP

Construct a new .DateTime.

Parameters
timezone	boolean. Indicates that the datetime type should enable timezone support, if available on the base date/time-holding type only. It is recommended to make use of the `_types.TIMESTAMP` datatype directly when using this flag, as some databases include separate generic date/time-holding types distinct from the timezone-capable TIMESTAMP datatype, such as Oracle.

def get_dbapi_type(self, dbapi):

overrides sqlalchemy.types.TypeEngine.get_dbapi_type

overridden in sqlalchemy.types.TIMESTAMP, sqlalchemy.dialects.postgresql.asyncpg.AsyncpgDateTime, sqlalchemy.dialects.postgresql.pg8000._PGTimeStamp

Return the corresponding type object from the underlying DB-API, if any.

This can be useful for calling setinputsizes(), for example.

def _resolve_for_literal(self, value):

overrides sqlalchemy.types.TypeEngine._resolve_for_literal

adjust this type given a literal Python value that will be stored in a bound parameter.

Used exclusively by _resolve_value_to_type().

New in version 1.4.30: or 2.0

__visit_name__: str =

overridden in sqlalchemy.dialects.mssql.DATETIME2, sqlalchemy.dialects.mssql.DATETIMEOFFSET, sqlalchemy.dialects.mssql.SMALLDATETIME, sqlalchemy.dialects.oracle.DATE, sqlalchemy.types.DATETIME, sqlalchemy.types.TIMESTAMP

Undocumented

timezone =

Undocumented

@util.memoized_property
_expression_adaptations =

overrides sqlalchemy.sql.sqltypes._LookupExpressionAdapter._expression_adaptations

Undocumented

@property
python_type =

overrides sqlalchemy.types.TypeEngine.python_type

Return the Python type object expected to be returned by instances of this type, if known.

Basically, for those types which enforce a return type, or are known across the board to do such for all common DBAPIs (like int for example), will return that type.

If a return type is not defined, raises NotImplementedError.

Note that any type also accommodates NULL in SQL which means you can also get back None from any type in practice.