class _FloatType(_NumericType, sqltypes.Float):
Known subclasses: sqlalchemy.dialects.mysql.types.DOUBLE
, sqlalchemy.dialects.mysql.types.FLOAT
, sqlalchemy.dialects.mysql.types.REAL
Undocumented
Method | __init__ |
Construct a Float. |
Method | __repr__ |
Undocumented |
Instance Variable | scale |
Undocumented |
Inherited from _NumericType
:
Instance Variable | unsigned |
Undocumented |
Instance Variable | zerofill |
Undocumented |
Inherited from Float
:
Method | result_processor |
Return a conversion function for processing result row values. |
Class Variable | __visit_name__ |
Undocumented |
Instance Variable | asdecimal |
Undocumented |
Instance Variable | decimal_return_scale |
Undocumented |
Instance Variable | precision |
Undocumented |
Inherited from Numeric
(via Float
):
Method | bind_processor |
Return a conversion function for processing bind values. |
Method | get_dbapi_type |
Return the corresponding type object from the underlying DB-API, if any. |
Method | literal_processor |
Return a conversion function for processing literal values that are to be rendered directly without using binds. |
Class Variable | _default_decimal_return_scale |
Undocumented |
Property | _effective_decimal_return_scale |
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
(via Float
, Numeric
):
Class | Comparator |
Undocumented |
Inherited from TypeEngine
(via Float
, Numeric
):
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 | 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 | 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 | __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 | _resolve_for_literal |
adjust this type given a literal Python value that will be stored in a bound parameter. |
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 Float
, Numeric
, TypeEngine
):
Method | get_children |
Return immediate child .visitors.Traversible elements of this .visitors.Traversible . |
Method | __class_getitem__ |
Undocumented |
sqlalchemy.dialects.mysql.types.DOUBLE
, sqlalchemy.dialects.mysql.types.FLOAT
, sqlalchemy.dialects.mysql.types.REAL
Parameters | |
precision | the numeric precision for use in DDL CREATE TABLE. |
scale | Undocumented |
asdecimal | the same flag as that of .Numeric , but
defaults to False. Note that setting this flag to True
results in floating point conversion. |
**kw | Undocumented |
decimal_return_scale | Default scale to use when converting from floats to Python decimals. Floating point values will typically be much longer due to decimal inaccuracy, and most floating point database types don't have a notion of "scale", so by default the float type looks for the first ten decimal places when converting. Specifying this value will override that length. Note that the MySQL float types, which do include "scale", will use "scale" as the default for decimal_return_scale, if not otherwise specified.
New in version 0.9.0.
|