Fixed issue in SQL math negation operator where the type of the
expression would no longer be the numeric type of the original.
This would cause issues where the type determined result set
behaviors.
Change-Id: If0e339614a3686e251235fc94b6f59310c4630a5
Fixes: #3735
(cherry picked from commit 5c60aaefd3)
override with a column expression (e.g. by using ``'x' in col``)
would cause an endless loop in the case of an ARRAY type, as Python
defers this to ``__getitem__`` access which never raises for this
type. Overall, all use of ``__contains__`` now raises
NotImplementedError.
fixes#3642
(cherry picked from commit e0a580b3d0)
a type that was also a :class:`.TypeDecorator` would fail with
Python's "Cannot create a consistent method resolution order (MRO)"
error, when any kind of SQL comparison expression were used against
an object using this type.
return type is not strictly assumed to be boolean; it now
returns a :class:`.Boolean` subclass called :class:`.MatchType`.
The type will still produce boolean behavior when used in Python
expressions, however the dialect can override its behavior at
result time. In the case of MySQL, while the MATCH operator
is typically used in a boolean context within an expression,
if one actually queries for the value of a match expression, a
floating point value is returned; this value is not compatible
with SQLAlchemy's C-based boolean processor, so MySQL's result-set
behavior now follows that of the :class:`.Float` type.
A new operator object ``notmatch_op`` is also added to better allow
dialects to define the negation of a match operation.
fixes#3263
of the "constants" :func:`.null`, :func:`.true`, and :func:`.false`
has been reverted. These functions returning a "singleton" object
had the effect that different instances would be treated as the
same regardless of lexical use, which in particular would impact
the rendering of the columns clause of a SELECT statement.
fixes#3170
system, whereby using a :class:`.TypeDecorator` in conjunction with
variant would fail with an MRO error when a comparison operator was used.
fixes#3102
:meth:`.Operators.__or__` and :meth:`.Operators.__invert__`
operator overload methods could not be overridden within a custom
:class:`.TypeEngine.Comparator` implementation.
fixes#3012
the new rules for "where" and "having" woudn't take effect for the
"whereclause" and "having" kw arguments of the :func:`.select` construct,
which is also what :class:`.Query` uses so wasn't working in the
ORM either. fixes#3013 re: #2804
renders "BETWEEN SYMMETRIC". Also added a new negation operator
"notbetween_op", which now allows an expression like ``~col.between(x, y)``
to render as "col NOT BETWEEN x AND y", rather than a parentheiszed NOT
string. fixes#2990
the first SQL expression would be applied as the "comparison type"
to a compared tuple value; this has the effect in some cases of an
inappropriate "type coersion" occurring, such as when a tuple that
has a mix of String and Binary values improperly coerces target
values to Binary even though that's not what they are on the left
side. :func:`.tuple_` now expects heterogeneous types within its
list of values.
fixes#2977
erroneously passed a column expression whose comparator included
the ``__getitem__()`` method, such as a column that uses the
:class:`.postgresql.ARRAY` type. [ticket:2957]
flag allows a custom op from :meth:`.Operators.op` to be considered
as a "comparison" operator, thus usable for custom
:paramref:`.relationship.primaryjoin` conditions.
have been modified, such that the COLLATE operator is now of lower
precedence than the comparison operators. This has the effect that
a COLLATE applied to a comparison will not render parenthesis
around the comparison, which is not parsed by backends such as
MSSQL. The change is backwards incompatible for those setups that
were working around the issue by applying :meth:`.Operators.collate`
to an individual element of the comparison expression,
rather than the comparison expression as a whole. [ticket:2879]
with conjunctions, e.g.
``None`` :func:`.expression.null` :func:`.expression.true`
:func:`.expression.false`, including consistency in rendering NULL
in conjunctions, "short-circuiting" of :func:`.and_` and :func:`.or_`
expressions which contain boolean constants, and rendering of
boolean constants and expressions as compared to "1" or "0" for backends
that don't feature ``true``/``false`` constants. [ticket:2804]
regards to the True/False constants. An expression like
``col.is_(True)`` will now render ``col IS true``
on the target platform, rather than converting the True/
False constant to an integer bound parameter.
This allows the ``is_()`` operator to work on MySQL when
given True/False constants.
[ticket:2682]
:class:`.ColumnElement` would go into an endless loop, if
:meth:`.ColumnOperators.__getitem__` were implemented.
A new NotImplementedError is emitted via ``__iter__()``.
become an externally usable package but still remains within the main sqlalchemy parent package.
in this system, we use kind of an ugly hack to get the noseplugin imported outside of the
"sqlalchemy" package, while still making it available within sqlalchemy for usage by
third party libraries.
"concat" and "match" operators to be the same as
that of "is", "like", and others; this helps with
parenthesization rendering when used in conjunction
with "IS". [ticket:2564]
contains() operators to do a better job with
negation (NOT LIKE), and also to assemble them
at compilation time so that their rendered SQL
can be altered, such as in the case for Firebird
STARTING WITH [ticket:2470]
- [feature] firebird - The "startswith()" operator renders
as "STARTING WITH", "~startswith()" renders
as "NOT STARTING WITH", using FB's more efficient
operator. [ticket:2470]
the `getitem` operator, i.e. the bracket
operator in Python. This is used at first
to provide index and slice behavior to the
Postgresql ARRAY type, and also provides a hook
for end-user definition of custom __getitem__
schemes which can be applied at the type
level as well as within ORM-level custom
operator schemes.
Note that this change has the effect that
descriptor-based __getitem__ schemes used by
the ORM in conjunction with synonym() or other
"descriptor-wrapped" schemes will need
to start using a custom comparator in order
to maintain this behavior.
- [feature] postgresql.ARRAY now supports
indexing and slicing. The Python [] operator
is available on all SQL expressions that are
of type ARRAY; integer or simple slices can be
passed. The slices can also be used on the
assignment side in the SET clause of an UPDATE
statement by passing them into Update.values();
see the docs for examples.
- [feature] Added new "array literal" construct
postgresql.array(). Basically a "tuple" that
renders as ARRAY[1,2,3].
its original role as stateful, forms the basis of TypeEngine.Comparator. lots
of code goes back mostly as it was just with cleaner typing behavior, such
as simple flow in _binary_operate now.
- [feature] Custom unary operators can now be
used by combining operators.custom_op() with
UnaryExpression().
- clean up the operator dispatch system and make it more consistent.
This does change the compiler contract for custom ops.
Mike Bayer