Commit Graph

174 Commits

Author SHA1 Message Date
Mike Bayer 7842678484 Column._copy() duplicates "user defined" nullable state exactly
To accommodate how mapped_column() works, after many
attempts to get this working it became clear that _copy()
should just transfer "nullable" state exactly as it was,
including the state where .nullable was set but user_defined_nullable
remains at not user set.

additionally, added a similar step to _merge() that was needed
to preserve the nullability behavior when Identity is present.

server / client default objects are not copied within column._copy()
and this should be fixed.

Fixes: #8410
Change-Id: Ib09df52b71f3e58e67e9f19b893d40a6cc4eec5c
2022-08-21 11:58:20 -04:00
Mike Bayer 26c0e8e184 implement column._merge()
this takes the user-defined args of one Column and merges
them into the not-user-defined args of another Column.

Implemented within the pep-593 column transfer operation
to begin to make this new feature more robust.

work may still be needed for constraints etc. but
in theory everything from the left side annotated column
should take effect for the right side if not otherwise
specified on the right.

Change-Id: I57eb37ed6ceb4b60979a35cfc4b63731d990911d
2022-07-16 17:41:09 -04:00
cheremnov 5fb63bc142 Comments on (named) constraints
Adds support for comments on named constraints, including `ForeignKeyConstraint`, `PrimaryKeyConstraint`, `CheckConstraint`, `UniqueConstraint`, solving the [Issue 5667](https://github.com/sqlalchemy/sqlalchemy/issues/5667).

Supports only PostgreSQL backend.

### Description

Following the example of [Issue 1546](https://github.com/sqlalchemy/sqlalchemy/issues/1546), supports comments on constraints. Specifically, enables comments on _named_ ones — as I get it, PostgreSQL prohibits comments on unnamed constraints.

Enables setting the comments for named constraints like this:
```
Table(
   'example', metadata,
   Column('id', Integer),
   Column('data', sa.String(30)),
   PrimaryKeyConstraint(
       "id", name="id_pk", comment="id_pk comment"
    ),
   CheckConstraint('id < 100', name="cc1", comment="Id value can't exceed 100"),
   UniqueConstraint(['data'], name="uc1", comment="Must have unique data field"),
)
```

Provides the DDL representation for constraint comments and routines to create and drop them. Class `.Inspector` reflects constraint comments via methods like `get_check_constraints` .
### Checklist
<!-- go over following points. check them with an `x` if they do apply, (they turn into clickable checkboxes once the PR is submitted, so no need to do everything at once)

-->

This pull request is:

- [ ] A documentation / typographical error fix
- [ ] A short code fix
- [x] A new feature implementation
	- Solves the issue 5667.
	- The commit message includes `Fixes: 5667`.
	- Includes tests based on comment reflection.

**Have a nice day!**

Fixes: #5667
Closes: #7742
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/7742
Pull-request-sha: 42a5d3c3e9

Change-Id: Ia60f578595afdbd6089541c9a00e37997ef78ad3
2022-06-29 09:13:37 +00:00
Mike Bayer ad11c482e2 pep484 ORM / SQL result support
after some experimentation it seems mypy is more amenable
to the generic types being fully integrated rather than
having separate spin-off types.   so key structures
like Result, Row, Select become generic.  For DML
Insert, Update, Delete, these are spun into type-specific
subclasses ReturningInsert, ReturningUpdate, ReturningDelete,
which is fine since the "row-ness" of these constructs
doesn't happen until returning() is called in any case.

a Tuple based model is then integrated so that these
objects can carry along information about their return
types.  Overloads at the .execute() level carry through
the Tuple from the invoked object to the result.

To suit the issue of AliasedClass generating attributes
that are dynamic, experimented with a custom subclass
AsAliased, but then just settled on having aliased()
lie to the type checker and return `Type[_O]`, essentially.
will need some type-related accessors for with_polymorphic()
also.

Additionally, identified an issue in Update when used
"mysql style" against a join(), it basically doesn't work
if asked to UPDATE two tables on the same column name.
added an error message to the specific condition where
it happens with a very non-specific error message that we
hit a thing we can't do right now, suggest multi-table
update as a possible cause.

Change-Id: I5eff7eefe1d6166ee74160b2785c5e6a81fa8b95
2022-04-27 14:46:36 -04:00
Mike Bayer 3da3322ec4 forwards port test cases and changelog for #7958 to 2.0
in 6f02d5edd8 some cleanup
to ForeignKey repaired the use case of ForeignKey objects
referring to table name alone, by adding more robust
column resolution logic.  This change also fixes an issue
where the "referred column" naming convention key uses the
resolved referred column earlier than usual when a
ForeignKey is setting up its constraint.

change message for 1.4:

Fixed bug where :class:`.ForeignKeyConstraint` naming conventions using the
``referred_column_0`` naming convention key would not work if the foreign
key constraint were set up as a :class:`.ForeignKey` object rather than an
explicit :class:`.ForeignKeyConstraint` object. As this change makes use of
a backport of some fixes from version 2.0, an additional little-known
feature that has likely been broken for many years is also fixed which is
that a :class:`.ForeignKey` object may refer to a referred table by name of
the table alone without using a column name, if the name of the referent
column is the same as that of the referred column.

The ``referred_column_0`` naming convention key was not previously not
tested with the :class:`.ForeignKey` object, only
:class:`.ForeignKeyConstraint`, and this bug reveals that the feature has
never worked correctly unless :class:`.ForeignKeyConstraint` is used for
all FK constraints. This bug traces back to the original introduction of
the feature introduced for 🎫`3989`.

Fixes: #7958
Change-Id: I230d43e9deba5dff889b9e7fee6cd4d3aa2496d3
(cherry picked from commit e32937fa6a)
2022-04-24 16:42:52 -04:00
Mike Bayer 74d3f3965b support BLANK_SCHEMA, RETAIN_SCHEMA FK schema on copy
Added support so that the :paramref:`.Table.tometadata.referred_schema_fn`
callable passed to :meth:`.Table.to_metadata` may return the value
:data:`.BLANK_SCHEMA` to indicate that the referenced foreign key should be
reset to None. The :data.`RETAIN_SCHEMA` symbol may also be returned from
this function to indicate "no change", which will behave the same as
``None`` currently does which also indicates no change.

Fixes: #7860
Change-Id: I82a45988d534295d8356453f68001b21d4ff706d
2022-03-26 10:11:31 -04:00
Mike Bayer 6f02d5edd8 pep484 - SQL internals
non-strict checking for mostly internal or semi-internal
code

Change-Id: Ib91b47f1a8ccc15e666b94bad1ce78c4ab15b0ec
2022-03-24 16:57:30 -04:00
Mike Bayer 6c3d738757 pep 484 for types
strict types type_api.py, including TypeDecorator,
NativeForEmulated, etc.

Change-Id: Ib2eba26de0981324a83733954cb7044a29bbd7db
2022-03-19 23:15:15 -04:00
Mike Bayer e545298e35 establish mypy / typing approach for v2.0
large patch to get ORM / typing efforts started.
this is to support adding new test cases to mypy,
support dropping sqlalchemy2-stubs entirely from the
test suite, validate major ORM typing reorganization
to eliminate the need for the mypy plugin.

* New declarative approach which uses annotation
  introspection, fixes: #7535
* Mapped[] is now at the base of all ORM constructs
  that find themselves in classes, to support direct
  typing without plugins
* Mypy plugin updated for new typing structures
* Mypy test suite broken out into "plugin" tests vs.
  "plain" tests, and enhanced to better support test
  structures where we assert that various objects are
  introspected by the type checker as we expect.
  as we go forward with typing, we will
  add new use cases to "plain" where we can assert that
  types are introspected as we expect.
* For typing support, users will be much more exposed to the
  class names of things.  Add these all to "sqlalchemy" import
  space.
* Column(ForeignKey()) no longer needs to be `@declared_attr`
  if the FK refers to a remote table
* composite() attributes mapped to a dataclass no longer
  need to implement a `__composite_values__()` method
* with_variant() accepts multiple dialect names

Change-Id: I22797c0be73a8fbbd2d6f5e0c0b7258b17fe145d
Fixes: #7535
Fixes: #7551
References: #6810
2022-02-13 14:23:04 -05:00
Mike Bayer de0b4db838 dont use exception catches for warnings; modernize xdist detection
Improvements to the test suite's integration with pytest such that the
"warnings" plugin, if manually enabled, will not interfere with the test
suite, such that third parties can enable the warnings plugin or make use
of the ``-W`` parameter and SQLAlchemy's test suite will continue to pass.
Additionally, modernized the detection of the "pytest-xdist" plugin so that
plugins can be globally disabled using PYTEST_DISABLE_PLUGIN_AUTOLOAD=1
without breaking the test suite if xdist were still installed. Warning
filters that promote deprecation warnings to errors are now localized to
SQLAlchemy-specific warnings, or within SQLAlchemy-specific sources for
general Python deprecation warnings, so that non-SQLAlchemy deprecation
warnings emitted from pytest plugins should also not impact the test suite.

Fixes: #7599
Change-Id: Ibcf09af25228d39ee5a943fda82d8a9302433726
2022-01-22 19:17:10 -05:00
Hugo van Kemenade 146a349d81 Update Black's target-version to py37
<!-- Provide a general summary of your proposed changes in the Title field above -->

### Description
<!-- Describe your changes in detail -->

Black's `target-version` was still set to `['py27', 'py36']`. Set it to `[py37]` instead.

Also update Black and other pre-commit hooks and re-format with Black.

### Checklist
<!-- go over following points. check them with an `x` if they do apply, (they turn into clickable checkboxes once the PR is submitted, so no need to do everything at once)

-->

This pull request is:

- [ ] A documentation / typographical error fix
	- Good to go, no issue or tests are needed
- [ ] A short code fix
	- please include the issue number, and create an issue if none exists, which
	  must include a complete example of the issue.  one line code fixes without an
	  issue and demonstration will not be accepted.
	- Please include: `Fixes: #<issue number>` in the commit message
	- please include tests.   one line code fixes without tests will not be accepted.
- [ ] A new feature implementation
	- please include the issue number, and create an issue if none exists, which must
	  include a complete example of how the feature would look.
	- Please include: `Fixes: #<issue number>` in the commit message
	- please include tests.

**Have a nice day!**

Closes: #7536
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/7536
Pull-request-sha: b3aedf5570

Change-Id: I8be85636fd2c9449b07a8626050c8bd35bd119d5
2022-01-05 12:41:32 -05:00
Mike Bayer f70b321661 Removals: MetaData.bind, Table.bind, all other .bind
Change-Id: I1ef2eb2018f4b68825fe40a2a8d99084cf217b35
References: #7257
2021-12-02 14:51:12 -05:00
Federico Caselli 0b95f0055b Remove object in class definition
References: #4600
Change-Id: I2a62ddfe00bc562720f0eae700a497495d7a987a
2021-11-22 15:03:17 +00:00
jonathan vanasco f5836f29f5 Fixes: #7295
Fixed issue in ``Table``` object where: param:`implicit_returning` was not
compatible with: param:`extend_existing`.
Change-Id: I16f4ab585d82f5691a3fed9eba04b84730a8a59e
2021-11-06 12:34:49 -04:00
Kai Mueller 7e5e40ff84 Fix missing None handling of Table.prefixes
Fixed issue where passing ``None`` for the value of
:paramref:`_schema.Table.prefixes` would not store an empty list, but
rather the constant ``None``, which may be unexpected by third party
dialects. The issue is revealed by a usage in recent versions of Alembic
that are passing ``None`` for this value. Pull request courtesy Kai
Mueller.

Fixes: #6685
Closes: #6672
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/6672
Pull-request-sha: b79aca0ee4

Change-Id: I758641c6fbde6f2607d074fecea7efa6728aeea0
2021-06-28 10:26:01 -04:00
Mike Bayer 6967b45020 don't cache TypeDecorator by default
The :class:`.TypeDecorator` class will now emit a warning when used in SQL
compilation with caching unless the ``.cache_ok`` flag is set to ``True``
or ``False``. ``.cache_ok`` indicates that all the parameters passed to the
object are safe to be used as a cache key, ``False`` means they are not.

Fixes: #6436
Change-Id: Ib1bb7dc4b124e38521d615c2e2e691e4915594fb
2021-05-06 13:57:43 -04:00
Mike Bayer 70c51bbe5e have SchemaType inherit schema from metadata
Fixed very old issue where the :class:`_types.Enum` datatype would not
inherit the :paramref:`_schema.MetaData.schema` parameter of a
:class:`_schema.MetaData` object when that object were passed to the
:class:`_types.Enum` using :paramref:`_types.Enum.metadata`.

Fixes: #6373
Change-Id: Ie77d5e8cbc0bd7bfd0039fb60a4a0bde2df58ca9
2021-04-27 13:13:52 -04:00
Federico Caselli 3de954bc02 Table arguments name and metadata are positional only
The :class:`_sql.Table` object now raises an informative error message if
it is instantiated without passing at least the :paramref:`_sql.Table.name`
and :paramref:`_sql.Table.metadata` arguments positionally. Previously, if
these were passed as keyword arguments, the object would silently fail to
initialize correctly.

Fixes: #6135
Change-Id: I54d0c89fd549fc504289a87ea0bb37369f982b06
2021-04-06 17:18:44 -04:00
Mike Bayer ab01f893f8 Correct for Variant + ARRAY cases in psycopg2
Fixed regression caused by 🎫`6023` where the PostgreSQL cast
operator applied to elements within an :class:`_types.ARRAY` when using
psycopg2 would fail to use the correct type in the case that the datatype
were also embedded within an instance of the :class:`_types.Variant`
adapter.

Additionally, repairs support for the correct CREATE TYPE to be emitted
when using a ``Variant(ARRAY(some_schema_type))``.

Fixes: #6182
Change-Id: I1b9ba7c876980d4650715a0b0801b46bdc72860d
2021-04-01 13:22:26 -04:00
Mike Bayer 3d284bb101 TypeDecorator passes "outer" flag to itself for set_parent accounting
Fixed bug first introduced in as some combination of 🎫`2892`,
🎫`2919` nnd 🎫`3832` where the attachment events for a
:class:`_types.TypeDecorator` would be doubled up against the "impl" class,
if the "impl" were also a :class:`_types.SchemaType`. The real-world case
is any :class:`_types.TypeDecorator` against :class:`_types.Enum` or
:class:`_types.Boolean` would get a doubled
:class:`_schema.CheckConstraint` when the ``create_constraint=True`` flag
is set.

Fixes: #6152
Change-Id: I3218b7081297270c132421f6765b5c3673d10a5c
2021-03-30 10:00:58 -04:00
Gord Thompson 506b88de5e Fix named CHECK constraint name omitted on repeated creates
Fixed issue where the CHECK constraint generated by :class:`_types.Boolean`
or :class:`_types.Enum` would fail to render the naming convention
correctly after the first compilation, due to an unintended change of state
within the name given to the constraint. This issue was first introduced in
0.9 in the fix for issue #3067, and the fix revises the approach taken at
that time which appears to have been more involved than what was needed.

Co-authored-by: Mike Bayer <mike_mp@zzzcomputing.com>
Fixes: #6007
Change-Id: I7ecff0a9d86191520f6841b3922a5af5a6971fba
2021-03-06 22:27:59 -05:00
Gord Thompson deaefbe748 Deprecate and rename schema .copy() methods
Fixes: #5953
Change-Id: I1e69a1628e408f06b43efbc0cc52fc0ad1e8cbc4
2021-02-18 15:25:08 -05:00
Mike Bayer 9660e94e35 Accommodate column-based naming conventions for pk constraint
Repaired / implemented support for primary key constraint naming
conventions that use column names/keys/etc as part of the convention. In
particular, this includes that the :class:`.PrimaryKeyConstraint` object
that's automatically associated with a :class:`.schema.Table` will update
its name as new primary key :class:`_schema.Column` objects are added to
the table and then to the constraint. Internal failure modes related to
this constraint construction process including no columns present, no name
present or blank name present are now accommodated.

Fixes: #5919
Change-Id: Ic2800b50f4a4cd5978bec48cefea0a2e198e0123
2021-02-04 12:11:41 -05:00
Gord Thompson 09e999808a Use schema._copy_expression() fully in column collection constraints
Fixed issue where using :meth:`_schema.Table.to_metadata` (called
:meth:`_schema.Table.tometadata` in 1.3) in conjunction with a PostgreSQL
:class:`_postgresql.ExcludeConstraint` that made use of ad-hoc column
expressions would fail to copy correctly.

Fixes: #5850
Change-Id: I062480afb23f6f60962b7b55bc93f5e4e6ff05e4
2021-01-29 16:48:00 -05:00
Federico Caselli 3ebc3710a7 `Identity implies nullable=False`.
Altered the behavior of the :class:`_schema.Identity` construct such that
when applied to a :class:`_schema.Column`, it will automatically imply that
the value of :paramref:`_sql.Column.nullable` should default to ``False``,
in a similar manner as when the :paramref:`_sql.Column.primary_key`
parameter is set to ``True``.   This matches the default behavior of all
supporting databases where ``IDENTITY`` implies ``NOT NULL``.  The
PostgreSQL backend is the only one that supports adding ``NULL`` to an
``IDENTITY`` column, which is here supported by passing a ``True`` value
for the :paramref:`_sql.Column.nullable` parameter at the same time.

Fixes: #5775
Change-Id: I0516d506ff327cff35cda605e8897a27440e0373
2021-01-16 18:39:11 -05:00
Mike Bayer f1e96cb087 reinvent xdist hooks in terms of pytest fixtures
To allow the "connection" pytest fixture and others work
correctly in conjunction with setup/teardown that expects
to be external to the transaction, remove and prevent any usage
of "xdist" style names that are hardcoded by pytest to run
inside of fixtures, even function level ones.   Instead use
pytest autouse fixtures to implement our own
r"setup|teardown_test(?:_class)?" methods so that we can ensure
function-scoped fixtures are run within them.   A new more
explicit flow is set up within plugin_base and pytestplugin
such that the order of setup/teardown steps, which there are now
many, is fully documented and controllable.   New granularity
has been added to the test teardown phase to distinguish
between "end of the test" when lock-holding structures on
connections should be released to allow for table drops,
vs. "end of the test plus its teardown steps" when we can
perform final cleanup on connections and run assertions
that everything is closed out.

From there we can remove most of the defensive "tear down everything"
logic inside of engines which for many years would frequently dispose
of pools over and over again, creating for a broken and expensive
connection flow.  A quick test shows that running test/sql/ against
a single Postgresql engine with the new approach uses 75% fewer new
connections, creating 42 new connections total, vs. 164 new
connections total with the previous system.

As part of this, the new fixtures metadata/connection/future_connection
have been integrated such that they can be combined together
effectively.  The fixture_session(), provide_metadata() fixtures
have been improved, including that fixture_session() now strongly
references sessions which are explicitly torn down before
table drops occur afer a test.

Major changes have been made to the
ConnectionKiller such that it now features different "scopes" for
testing engines and will limit its cleanup to those testing
engines corresponding to end of test, end of test class, or
end of test session.   The system by which it tracks DBAPI
connections has been reworked, is ultimately somewhat similar to
how it worked before but is organized more clearly along
with the proxy-tracking logic.  A "testing_engine" fixture
is also added that works as a pytest fixture rather than a
standalone function.  The connection cleanup logic should
now be very robust, as we now can use the same global
connection pools for the whole suite without ever disposing
them, while also running a query for PostgreSQL
locks remaining after every test and assert there are no open
transactions leaking between tests at all.  Additional steps
are added that also accommodate for asyncio connections not
explicitly closed, as is the case for legacy sync-style
tests as well as the async tests themselves.

As always, hundreds of tests are further refined to use the
new fixtures where problems with loose connections were identified,
largely as a result of the new PostgreSQL assertions,
many more tests have moved from legacy patterns into the newest.

An unfortunate discovery during the creation of this system is that
autouse fixtures (as well as if they are set up by
@pytest.mark.usefixtures) are not usable at our current scale with pytest
4.6.11 running under Python 2.  It's unclear if this is due
to the older version of pytest or how it implements itself for
Python 2, as well as if the issue is CPU slowness or just large
memory use, but collecting the full span of tests takes over
a minute for a single process when any autouse fixtures are in
place and on CI the jobs just time out after ten minutes.
So at the moment this patch also reinvents a small version of
"autouse" fixtures when py2k is running, which skips generating
the real fixture and instead uses two global pytest fixtures
(which don't seem to impact performance) to invoke the
"autouse" fixtures ourselves outside of pytest.
This will limit our ability to do more with fixtures
until we can remove py2k support.

py.test is still observed to be much slower in collection in the
4.6.11 version compared to modern 6.2 versions, so add support for new
TOX_POSTGRESQL_PY2K and TOX_MYSQL_PY2K environment variables that
will run the suite for fewer backends under Python 2.  For Python 3
pin pytest to modern 6.2 versions where performance for collection
has been improved greatly.

Includes the following improvements:

Fixed bug in asyncio connection pool where ``asyncio.TimeoutError`` would
be raised rather than :class:`.exc.TimeoutError`.  Also repaired the
:paramref:`_sa.create_engine.pool_timeout` parameter set to zero when using
the async engine, which previously would ignore the timeout and block
rather than timing out immediately as is the behavior with regular
:class:`.QueuePool`.

For asyncio the connection pool will now also not interact
at all with an asyncio connection whose ConnectionFairy is
being garbage collected; a warning that the connection was
not properly closed is emitted and the connection is discarded.
Within the test suite the ConnectionKiller is now maintaining
strong references to all DBAPI connections and ensuring they
are released when tests end, including those whose ConnectionFairy
proxies are GCed.

Identified cx_Oracle.stmtcachesize as a major factor in Oracle
test scalability issues, this can be reset on a per-test basis
rather than setting it to zero across the board.  the addition
of this flag has resolved the long-standing oracle "two task"
error problem.

For SQL Server, changed the temp table style used by the
"suite" tests to be the double-pound-sign, i.e. global,
variety, which is much easier to test generically.  There
are already reflection tests that are more finely tuned
to both styles of temp table within the mssql test
suite.  Additionally, added an extra step to the
"dropfirst" mechanism for SQL Server that will remove
all foreign key constraints first as some issues were
observed when using this flag when multiple schemas
had not been torn down.

Identified and fixed two subtle failure modes in the
engine, when commit/rollback fails in a begin()
context manager, the connection is explicitly closed,
and when "initialize()" fails on the first new connection
of a dialect, the transactional state on that connection
is still rolled back.

Fixes: #5826
Fixes: #5827
Change-Id: Ib1d05cb8c7cf84f9a4bfd23df397dc23c9329bfe
2021-01-13 22:10:13 -05:00
Mike Bayer 80be40300d Convert to autoload_with internally
Fixed bug where the now-deprecated ``autoload`` parameter was being called
internally within the reflection routines when a related table were
reflected.

Fixes: #5684
Change-Id: I6ab439a2f49ff1ae2d3c7a15b531cbafbc3cf594
2020-11-07 11:13:28 -05:00
Mike Bayer 654b462d66 tutorial 2.0 WIP
Add SelectBase.exists() method as it seems strange this is
not available already.  The Exists construct itself does
not provide full SELECT-building capabilities so it makes
sense this should be used more like a scalar_subquery.

Make sure stream_results is getting set up when yield_per
is used, for 2.0 style statements as well.  this was
hardcoded inside of Query.yield_per() and is now moved
to take place within QueryContext.

Change-Id: Icafcd4fd9b708772343d56edf40995c9e8f835d6
2020-10-31 13:44:53 -04:00
Mike Bayer 9e82f32f27 Deprecate duplicated column names in Table definition
The :class:`_schema.Table` class now raises a deprecation warning
when columns with the same name are defined. To replace a column a new
parameter :paramref:`_schema.Table.append_column.replace_existing` was
added to the :meth:`_schema.Table.append_column` method.

The :meth:`_expression.ColumnCollection.contains_column` will now
raises an error when called with a string, suggesting the caller
to use ``in`` instead.

Co-authored-by: Federico Caselli <cfederico87@gmail.com>
Change-Id: I1d58c8ebe081079cb669e7ead60886ffc1b1a7f5
2020-10-12 13:52:06 -04:00
Mike Bayer 9586594754 raise on lower-case column shared to multiple tables
Fixed bug where an error was not raised for lower-case
:func:`_column` added to lower-case :func:`_table` object. This now raises
:class:`_exc.ArgumentError` which has always been the case for
upper-case :class:`_schema.Column` and :class:`_schema.Table`.

Fixes: #5618
Change-Id: Ifcbdf27c022fd2996a5b99559df71fc1c1e0f19c
2020-09-30 09:37:02 -04:00
Mike Bayer c3f102c9fe upgrade to black 20.8b1
It's better, the majority of these changes look more readable to me.
also found some docstrings that had formatting / quoting issues.

Change-Id: I582a45fde3a5648b2f36bab96bad56881321899b
2020-09-28 15:17:26 -04:00
mike bayer a2f2863f5a Merge "Raname `mustexit to must_exist`" 2020-09-12 16:36:00 +00:00
Federico Caselli e860060866 Update select usage to use the new 1.4 format
This change includes mainly that the bracketed use within
select() is moved to positional, and keyword arguments are
removed from calls to the select() function.  it does not
yet fully address other issues such as keyword arguments passed
to the table.select().

Additionally, allows False / None to both be considered
as "disable" for all of select.correlate(), select.correlate_except(),
query.correlate(), which establishes consistency with
passing of ``False`` for the legact select(correlate=False)
argument.

Change-Id: Ie6c6e6abfbd3d75d4c8de504c0cf0159e6999108
2020-09-08 17:13:48 -04:00
Federico Caselli bcfb12f813 Raname `mustexit to must_exist`
:class:`_schema.Table` parameter ``mustexist`` has been renamed
to :paramref:`_schema.Table.must_exist` and will now warn when used.

Change-Id: I0b0ca6021f9f7cfbe2040bbc1125a2236ac79f53
2020-09-03 23:46:35 +02:00
Mike Bayer 0721a6bede Genericize str() for types
Remove lookup logic that attempts to locate a dialect for a type,
just use StrSQLTypeCompiler.

Cleaned up the internal ``str()`` for datatypes so that all types produce a
string representation without any dialect present, including that it works
for third-party dialect types without that dialect being present.  The
string representation defaults to being the UPPERCASE name of that type
with nothing else.

Fixes: #4262
Change-Id: I02149e8a1ba1e7336149e962939b07ae0df83c6b
2020-08-01 19:49:15 -04:00
Gord Thompson 2c1e517d03 Rename Table.tometadata to to_metadata
Renamed the :meth:`_schema.Table.tometadata` method to
:meth:`_schema.Table.to_metadata`.  The previous name remains with a
deprecation warning.

Updated the "decorate" utility function to support decoration
of functions that include non-builtins as default values.

Moves test for deprecated "databases" package into
test/dialect/test_deprecations.py

Fixes: #5413
Fixes: #5426
Change-Id: I6ed899871c935f9e46360127c17ccb7cf97cea6e
2020-06-29 13:56:21 -04:00
Gord Thompson 5d7d96b53e Apply dialect_options copy fix
Fixes: #5276
Change-Id: Ic608310d4a85934fc9fa4d72daef66323c6e2525
2020-06-18 12:05:52 -06:00
Mike Bayer 97cd0a5db8 Default create_constraint to False
The :paramref:`.Enum.create_constraint` and
:paramref:`.Boolean.create_constraint` parameters now default to False,
indicating when a so-called "non-native" version of these two datatypes is
created, a CHECK constraint will not be generated by default.   These CHECK
constraints present schema-management maintenance complexities that should
be opted in to, rather than being turned on by default.

Fixes: #5367
Change-Id: I0a3fb608ce32143fa757546cc17ba2013e93272a
2020-06-03 16:19:40 -04:00
Mike Bayer fcbd03e48a Add immutabledict C code
Start trying to convert fundamental objects to
C as we now rely on a fairly small core of things,
and 1.4 is having problems with complexity added being
slower than the performance gains we are trying to build in.

immutabledict here does seem to bench as twice as fast as the
Python one, see below.  However, it does not appear to be
used prominently enough to make any dent in the performance
tests.

at the very least it may provide us some more lift-and-copy
code for more C extensions.

import timeit

from sqlalchemy.util._collections import not_immutabledict, immutabledict

def run(dict_cls):
    for i in range(1000000):
        d1 = dict_cls({"x": 5, "y": 4})

        d2 = d1.union({"x": 17, "new key": "some other value"}, None)

        assert list(d2) == ["x", "y", "new key"]

print(
    timeit.timeit(
        "run(d)", "from __main__ import run, not_immutabledict as d", number=1
    )
)
print(
    timeit.timeit(
        "run(d)", "from __main__ import run, immutabledict as d", number=1
    )
)

output:

python: 1.8799766399897635
C code: 0.8880784640205093

Change-Id: I29e7104dc21dcc7cdf895bf274003af2e219bf6d
2020-05-23 00:05:13 -04:00
Mike Bayer 8782469b78 Warn when sorted_tables is not actually sorting
A warning is emitted when making use of the :attr:`.MetaData.sorted_tables`
attribute as well as the :func:`_schema.sort_tables` function, and the
given tables cannot be correctly sorted due to a cyclic dependency between
foreign key constraints. In this case, the functions will no longer sort
the involved tables by foreign key, and a warning will be emitted. Other
tables that are not part of the cycle will still be returned in dependency
order. Previously, the sorted_table routines would return a collection that
would unconditionally omit all foreign keys when a cycle was detected, and
no warning was emitted.

Fixes: #5316
Change-Id: I14f72ccf39cb568bc77e8da16d0685718b2b9960
2020-05-07 19:56:32 -04:00
Mike Bayer 45a334e38c Handle non-string, non column expression in index for deferred attach
Fixed issue where an :class:`.Index` that is deferred in being associated
with a table, such as as when it contains a :class:`.Column` that is not
associated with any :class:`.Table` yet,  would fail to attach correctly if
it also contained a non table-oriented expession.

Fixes: #5298
Change-Id: I0111c400f6bd4a9f31bf00a9957816c7a3fac783
2020-05-01 20:58:42 -04:00
Gord Thompson 50cee43fbc Clean up .execute in test/sql/test_functions.py
Change-Id: I2bc7a50893f90c6ea7e119a8558731ee32965871
2020-04-20 07:46:24 -06:00
Federico Caselli 35b74d8a33 Add `comment attribute to :class:.Column __repr__` method.
Fixes #4138

Change-Id: Ia93f7d7b1d2f38509421725fbe152a2ff163d5f3
2020-04-11 20:50:37 +02:00
Federico Caselli 4bd4b483e0 Remove support for python 3.4
Also remove no longer used compat code

Change-Id: Ifda239fd84b425e43f4028cb55a5b3b8efa4dfc6
2020-03-30 00:35:33 +02:00
Mike Bayer 57dc36a01b Ensure all nested exception throws have a cause
Applied an explicit "cause" to most if not all internally raised exceptions
that are raised from within an internal exception catch, to avoid
misleading stacktraces that suggest an error within the handling of an
exception.  While it would be preferable to suppress the internally caught
exception in the way that the ``__suppress_context__`` attribute would,
there does not as yet seem to be a way to do this without suppressing an
enclosing user constructed context, so for now it exposes the internally
caught exception as the cause so that full information about the context
of the error is maintained.

Fixes: #4849
Change-Id: I55a86b29023675d9e5e49bc7edc5a2dc0bcd4751
2020-03-02 17:24:19 -05:00
Mike Bayer f7fe966a4c Remove ORM elements from annotations at the schema level.
Fixed issue where when constructing constraints from ORM-bound columns,
primarily :class:`.ForeignKey` objects but also :class:`.UniqueConstraint`,
:class:`.CheckConstraint` and others, the ORM-level
:class:`.InstrumentedAttribute` is discarded entirely, and all ORM-level
annotations from the columns are removed; this is so that the constraints
are still fully pickleable without the ORM-level entities being pulled in.
These annotations are not necessary to be present at the schema/metadata
level.

Fully implemented coercions for constraint columns within
schema.py, including for FK referenced columns.

Fixes: #5001
Change-Id: I895400dd979310be034085d207f096707c635909
2019-11-26 10:42:17 -05:00
CaselIT 3a0e0531c1 Support for generated columns
Added DDL support for "computed columns"; these are DDL column
specifications for columns that have a server-computed value, either upon
SELECT (known as "virtual") or at the point of which they are INSERTed or
UPDATEd (known as "stored").  Support is established for Postgresql, MySQL,
Oracle SQL Server and Firebird. Thanks to Federico Caselli for lots of work
on this one.

ORM round trip tests included.  The ORM makes use of existing
FetchedValue support and no additional ORM logic is present for
the basic feature.

It has been observed that Oracle RETURNING does not return the
new value of a computed column upon UPDATE; it returns the
prior value.  As this is very dangerous, a warning is emitted
if a computed column is rendered into the RETURNING clause
of an UPDATE statement.

Fixes: #4894
Closes: #4928
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/4928
Pull-request-sha: d39c521d5a

Change-Id: I2610b2999a5b1b127ed927dcdaeee98b769643ce
2019-11-08 15:40:25 -05:00
Mike Bayer 41dc71ad2f Use separate label generator for column_label naming convention
Fixed bug where a table that would have a column label overlap with a plain
column name, such as "foo.id AS foo_id" vs. "foo.foo_id", would prematurely
generate the ``._label`` attribute for a column before this overlap could
be detected due to the use of the ``index=True`` or ``unique=True`` flag on
the column in conjunction with the default naming convention of
``"column_0_label"``.  This would then lead to failures when ``._label``
were used later to generate a bound parameter name, in particular those
used by the ORM when generating the WHERE clause for an UPDATE statement.
The issue has been fixed by using an alternate ``._label`` accessor for DDL
generation that does not affect the state of the :class:`.Column`.   The
accessor also bypasses the key-deduplication step as it is not necessary
for DDL, the naming is now consistently ``"<tablename>_<columnname>"``
without any subsequent numeric symbols when used in DDL.

Fixes: #4911

Change-Id: Iabf5fd3250738d800d6e41a2a3a27a7ce2405e7d
2019-10-14 12:51:14 -04:00
Mike Bayer 7afcb39a96 Catch set_parent_w_dispatch missing
Added an explicit error message for the case when objects passed to
:class:`.Table` are not :class:`.SchemaItem` objects, rather than resolving
to an attribute error.

Fixes: #4847
Change-Id: I4dcdcee86b64c85ccf12e2ddc3d638563d307991
2019-09-06 18:43:58 -04:00
Mike Bayer aceefb508c Allow duplicate columns in from clauses and selectables
The :func:`.select` construct and related constructs now allow for
duplication of column labels and columns themselves in the columns clause,
mirroring exactly how column expressions were passed in.   This allows
the tuples returned by an executed result to match what was SELECTed
for in the first place, which is how the ORM :class:`.Query` works, so
this establishes better cross-compatibility between the two constructs.
Additionally, it allows column-positioning-sensitive structures such as
UNIONs (i.e. :class:`.CompoundSelect`) to be more intuitively constructed
in those cases where a particular column might appear in more than one
place.   To support this change, the :class:`.ColumnCollection` has been
revised to support duplicate columns as well as to allow integer index
access.

Fixes: #4753
Change-Id: Ie09a8116f05c367995c1e43623c51e07971d3bf0
2019-07-11 14:20:10 -04:00