Fixed bug where the recently added :meth:`.ColumnOperators.any_`
and :meth:`.ColumnOperators.all_` methods didn't work when called
as methods, as opposed to using the standalone functions
:func:`~.expression.any_` and :func:`~.expression.all_`. Also
added documentation examples for these relatively unintuitive
SQL operators.
Change-Id: I3e56b463e9fd146a077b9970624f50cba27f9811
Fixes: #4093
(cherry picked from commit 944c662d8a)
Added compiler-level flags used by Postgresql to place additional
parenthesis than would normally be generated by precedence rules
around operations involving JSON, HSTORE indexing operators as well as
within their operands since it has been observed that Postgresql's
precedence rules for at least the HSTORE indexing operator is not
consistent between 9.4 and 9.5.
Fixes: #3806
Change-Id: I5899677b330595264543b055abd54f3c76bfabf2
The "eq" and "ne" operators are no longer part of the list of
"associative" operators, while they remain considered to be
"commutative". This allows an expression like ``(x == y) == z``
to be maintained at the SQL level with parenthesis. Pull request
courtesy John Passaro.
Fixes: #3799
Change-Id: I3759d8987b35649d7418b6524316c9e70c857e68
Pull-request: https://github.com/zzzeek/sqlalchemy/pull/308
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
None / True / False render as literals.
For SQLite, "IS" is used as SQLite lacks
"IS DISTINCT FROM" but its "IS" operator acts
this way for NULL.
Doctext-author: Mike Bayer <mike_mp@zzzcomputing.com>
Change-Id: I9227b81f7207b42627a0349d14d40b46aa756cce
Pull-request: https://github.com/zzzeek/sqlalchemy/pull/248
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
persistence of JSON values in MySQL as well as basic operator support
of "getitem" and "getpath", making use of the ``JSON_EXTRACT``
function in order to refer to individual paths in a JSON structure.
fixes#3547
- Added a new type to core :class:`.types.JSON`. This is the
base of the PostgreSQL :class:`.postgresql.JSON` type as well as that
of the new :class:`.mysql.JSON` type, so that a PG/MySQL-agnostic
JSON column may be used. The type features basic index and path
searching support.
fixes#3619
- reorganization of migration docs etc. to try to refer both to
the fixes to JSON that helps Postgresql while at the same time
indicating these are new features of the new base JSON type.
- a rework of the Array/Indexable system some more, moving things
that are specific to Array out of Indexable.
- new operators for JSON indexing added to core so that these can
be compiled by the PG and MySQL dialects individually
- rename sqltypes.Array to sqltypes.ARRAY - as there is no generic
Array implementation, this is an uppercase type for now, consistent
with the new sqltypes.JSON type that is also not a generic implementation.
There may need to be some convention change to handle the case of
datatypes that aren't generic, rely upon DB-native implementations,
but aren't necessarily all named the same thing.
"super" instead of hardcoding to "self.type" for the default return
value, the base Comparator was returning other_comparator.type. It's
not clear what the rationale for this was, though in theory the
base Comparator should possibly even throw an exception if the two
types aren't the same (or of the same affinity?) .
- mysql.SET was broken on this because the bitwise version adds "0"
to the value to force an integer within column_expression, we are doing type_coerces here
now in any case so that there is no type ambiguity for this
operation
- The "hashable" flag on special datatypes such as :class:`.postgresql.ARRAY`,
:class:`.postgresql.JSON` and :class:`.postgresql.HSTORE` is now
set to False, which allows these types to be fetchable in ORM
queries that include entities within the row. fixes#3499
- The Postgresql :class:`.postgresql.ARRAY` type now supports multidimensional
indexed access, e.g. expressions such as ``somecol[5][6]`` without
any need for explicit casts or type coercions, provided
that the :paramref:`.postgresql.ARRAY.dimensions` parameter is set to the
desired number of dimensions. fixes#3487
- The return type for the :class:`.postgresql.JSON` and :class:`.postgresql.JSONB`
when using indexed access has been fixed to work like Postgresql itself,
and returns an expression that itself is of type :class:`.postgresql.JSON`
or :class:`.postgresql.JSONB`. Previously, the accessor would return
:class:`.NullType` which disallowed subsequent JSON-like operators to be
used. part of fixes#3503
- The :class:`.postgresql.JSON`, :class:`.postgresql.JSONB` and
:class:`.postgresql.HSTORE` datatypes now allow full control over the
return type from an indexed textual access operation, either ``column[someindex].astext``
for a JSON type or ``column[someindex]`` for an HSTORE type,
via the :paramref:`.postgresql.JSON.astext_type` and
:paramref:`.postgresql.HSTORE.text_type` parameters. also part of fixes#3503
- The :attr:`.postgresql.JSON.Comparator.astext` modifier no longer
calls upon :meth:`.ColumnElement.cast` implicitly, as PG's JSON/JSONB
types allow cross-casting between each other as well. Code that
makes use of :meth:`.ColumnElement.cast` on JSON indexed access,
e.g. ``col[someindex].cast(Integer)``, will need to be changed
to call :attr:`.postgresql.JSON.Comparator.astext` explicitly. This is
part of the refactor in references #3503 for consistency in operator
use.
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