summaryrefslogtreecommitdiff
path: root/lib/sqlalchemy/engine/base.py
Commit message (Collapse)AuthorAgeFilesLines
* 2.0 removals: LegacyRow, connectionless execution, close_with_resultMike Bayer2021-10-311-118/+19
| | | | | | | | | | | | | | | | | | | in order to remove LegacyRow / LegacyResult, we have to also lose close_with_result, which connectionless execution relies upon. also includes a new profiles.txt file that's all against py310, as that's what CI is on now. some result counts changed by one function call which was enough to fail the low-count result tests. Replaces Connectable as the common interface between Connection and Engine with EngineEventsTarget. Engine is no longer Connectable. Connection and MockConnection still are. References: #7257 Change-Id: Iad5eba0313836d347e65490349a22b061356896a
* Surface driver connection object when using a proxied dialectFederico Caselli2021-09-171-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | Improve the interface used by adapted drivers, like the asyncio ones, to access the actual connection object returned by the driver. The :class:`_engine._ConnectionRecord` and :class:`_engine._ConnectionFairy` now have two new attributes: * ``dbapi_connection`` always represents a DBAPI compatible object. For pep-249 drivers, this is the DBAPI connection as it always has been, previously accessed under the ``.connection`` attribute. For asyncio drivers that SQLAlchemy adapts into a pep-249 interface, the returned object will normally be a SQLAlchemy adaption object called :class:`_engine.AdaptedConnection`. * ``driver_connection`` always represents the actual connection object maintained by the third party pep-249 DBAPI or async driver in use. For standard pep-249 DBAPIs, this will always be the same object as that of the ``dbapi_connection``. For an asyncio driver, it will be the underlying asyncio-only connection object. The ``.connection`` attribute remains available and is now a legacy alias of ``.dbapi_connection``. Fixes: #6832 Change-Id: Ib72f97deefca96dce4e61e7c38ba430068d6a82e
* Add scalars method to connection and session classesMiguel Grinberg2021-09-141-0/+18
| | | | | | | | | | | | | | | | | | | | Added new methods :meth:`_orm.Session.scalars`, :meth:`_engine.Connection.scalars`, :meth:`_asyncio.AsyncSession.scalars` and :meth:`_asyncio.AsyncSession.stream_scalars`, which provide a short cut to the use case of receiving a row-oriented :class:`_result.Result` object and converting it to a :class:`_result.ScalarResult` object via the :meth:`_engine.Result.scalars` method, to return a list of values rather than a list of rows. The new methods are analogous to the long existing :meth:`_orm.Session.scalar` and :meth:`_engine.Connection.scalar` methods used to return a single value from the first row only. Pull request courtesy Miguel Grinberg. Fixes: #6990 Closes: #6991 Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/6991 Pull-request-sha: b3e0bb3042c55b0cc5af6a25cb3f31b929f88a47 Change-Id: Ia445775e24ca964b0162c2c8e5ca67dd1e39199f
* restore statement substitution to before_execute()Mike Bayer2021-08-201-1/+6
| | | | | | | | | | | | | | Fixed issue where the ability of the :meth:`_engine.ConnectionEvents.before_execute` method to alter the SQL statement object passed, returning the new object to be invoked, was inadvertently removed. This behavior has been restored. The refactor in a1939719a652774a437f69f8d4788b3f08650089 removed this feature for some reason and there were no tests in place to detect it. I don't see any indication this was planned. Fixes: #6913 Change-Id: Ia77ca08aa91ab9403f19a8eb61e2a0e41aad138a
* Replace all http:// links to https://Federico Caselli2021-07-041-3/+4
| | | | | | Also replace http://pypi.python.org/pypi with https://pypi.org/project Change-Id: I84b5005c39969a82140706472989f2a30b0c7685
* Fix typo in _warn_for_legacy_exec_formatgordthompson2021-06-241-1/+1
| | | | Change-Id: Idc24b5ab4b5a25fcfb7115c5d7be4c2ece520674
* Add Executable to DefaultGeneratorMike Bayer2021-06-231-1/+1
| | | | | | | | | | | | | | Fixed the class hierarchy for the :class:`_schema.Sequence` and the more general :class:`_schema.DefaultGenerator` base, as these are "executable" as statements they need to include :class:`_sql.Executable` in their hierarchy, not just :class:`_roles.StatementRole` as was applied arbitrarily to :class:`_schema.Sequence` previously. The fix allows :class:`_schema.Sequence` to work in all ``.execute()`` methods including with :meth:`_orm.Session.execute` which was not working in the case that a ``do_orm_execute()`` handler was also established. Fixes: #6668 Change-Id: I0d192258c7cbd1bce2552f9e748e8fdd680dc45f
* Add asyncio.TimeoutError as an exit exceptionMike Bayer2021-06-071-2/+1
| | | | | | | | | | | | Added ``asyncio.exceptions.TimeoutError``, ``asyncio.exceptions.CancelledError`` as so-called "exit exceptions", a class of exceptions that include things like ``GreenletExit`` and ``KeyboardInterrupt``, which are considered to be events that warrant considering a DBAPI connection to be in an unusable state where it should be recycled. Fixes: #6592 Change-Id: Idcfa7aaa2d7660838b907388db9c6457afa6edbd
* unify transactional context managersMike Bayer2021-05-051-21/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Applied consistent behavior to the use case of calling ``.commit()`` or ``.rollback()`` inside of an existing ``.begin()`` context manager, with the addition of potentially emitting SQL within the block subsequent to the commit or rollback. This change continues upon the change first added in :ticket:`6155` where the use case of calling "rollback" inside of a ``.begin()`` contextmanager block was proposed: * calling ``.commit()`` or ``.rollback()`` will now be allowed without error or warning within all scopes, including that of legacy and future :class:`_engine.Engine`, ORM :class:`_orm.Session`, asyncio :class:`.AsyncEngine`. Previously, the :class:`_orm.Session` disallowed this. * The remaining scope of the context manager is then closed; when the block ends, a check is emitted to see if the transaction was already ended, and if so the block returns without action. * It will now raise **an error** if subsequent SQL of any kind is emitted within the block, **after** ``.commit()`` or ``.rollback()`` is called. The block should be closed as the state of the executable object would otherwise be undefined in this state. Fixes: #6288 Change-Id: I8b21766ae430f0fa1ac5ef689f4c0fb19fc84336
* restore legacy begin_nested()->root transaction behaviorMike Bayer2021-05-021-17/+83
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Restored a legacy transactional behavior that was inadvertently removed from the :class:`_engine.Connection` as it was never tested as a known use case in previous versions, where calling upon the :meth:`_engine.Connection.begin_nested` method, when no transaction were present, would not create a SAVEPOINT at all, and would instead only start the outermost transaction alone, and return that :class:`.RootTransaction` object, acting like the outermost transaction. Committing the transaction object returned by :meth:`_engine.Connection.begin_nested` would therefore emit a real COMMIT on the database connection. This behavior is not at all what the 2.0 style connection will do - in 2.0 style, calling :meth:`_future.Connection.begin_nested` will "autobegin" the outer transaction, and then as instructed emit a SAVEPOINT, returning the :class:`.NestedTransaction` object. The outer transaction is committed by calling upon :meth:`_future.Connection.commit`, as is "commit-as-you-go" style usage. In non-"future" mode, while the old behavior is restored, it also emits a 2.0 deprecation warning as this is a legacy behavior. Additionally clarifies and reformats various engine-related documentation, in particular future connection.begin() which was a tire fire. Fixes: #6408 Change-Id: I4b81cc6b481b5493eef4c91bebc03210e2206d39
* Add new "sync once" mode for pool.connectMike Bayer2021-04-211-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fixed critical regression caused by the change in :ticket`5497` where the connection pool "init" phase no longer occurred within mutexed isolation, allowing other threads to proceed with the dialect uninitialized, which could then impact the compilation of SQL statements. This issue is essentially the same regression which was fixed many years ago in :ticket:`2964` in dd32540dabbee0678530fb1b0868d1eb41572dca, which was missed this time as the test suite fo that issue only tested the pool in isolation, and assumed the "first_connect" event would be used by the Engine. However :ticket:`5497` stopped using "first_connect" and no test detected the lack of mutexing, that has been resolved here through the addition of more tests. This fix also identifies what is probably a bug in earlier versions of SQLAlchemy where the "first_connect" handler would be cancelled if the initializer failed; this is evidenced by test_explode_in_initializer which was doing a reconnect due to c.rollback() yet wasn't hanging. We now solve this issue by preventing the manufactured Connection from ever reconnecting inside the first_connect handler. Also remove the "_sqla_unwrap" test attribute; this is almost not used anymore however we can use a more targeted wrapper supplied by the testing.engines.proxying_engine function. See if we can also open up Oracle for "ad hoc engines" tests now that we have better connection management logic. Fixes: #6337 Change-Id: I4a3476625c4606f1a304dbc940d500325e8adc1a
* Update run_callable depr warn to suggest .begin()Gord Thompson2021-04-081-1/+1
| | | | Change-Id: Ie5dd908710520fc94169393f826f80a2249ee77f
* Run trans.close() at end of block if transaction already inactiveMike Bayer2021-03-301-8/+36
| | | | | | | | | | | | Modified the context manager used by :class:`_engine.Transaction` so that an "already detached" warning is not emitted by the ending of the context manager itself, if the transaction were already manually rolled back inside the block. This applies to regular transactions, savepoint transactions, and legacy "marker" transactions. A warning is still emitted if the ``.rollback()`` method is called explicitly more than once. Fixes: #6155 Change-Id: Ib9f9d803bf377ec843d4a8a09da8ebef4b441665
* Reword deprecation message for Connection.run_callable()Mike Bayer2021-03-161-1/+2
| | | | | | | based on feedback at https://github.com/sqlalchemy/sqlalchemy/commit/00b5c10846e800304caa86549ab9da373b42fa5d#r48321551 Change-Id: Ibdf4b4fb86af0b8f282a7866883837915ea2934e
* documentation updatesMike Bayer2021-03-151-5/+12
| | | | Change-Id: I43d0e8de1f90abcff4b278637808d1ebc8fd6c97
* Document NestedTransactionMike Bayer2021-03-141-5/+68
| | | | | Fixes: #3550 Change-Id: Ic2ff36ea434923590d2adbd101580025da319f66
* Replace reset_agent with direct call from connectionMike Bayer2021-03-061-32/+9
| | | | | | | | | | | | | Fixed a regression where the "reset agent" of the connection pool wasn't really being utilized by the :class:`_engine.Connection` when it were closed, and also leading to a double-rollback scenario that was somewhat wasteful. The newer architecture of the engine has been updated so that the connection pool "reset-on-return" logic will be skipped when the :class:`_engine.Connection` explicitly closes out the transaction before returning the pool to the connection. Fixes: #6004 Change-Id: I5d2ac16cac71aa45a00b4b7481d7268bd828a168
* Clarify COMMIT/ROLLBACK logging when autocommit is turned onMike Bayer2021-03-051-7/+29
| | | | | | | | | | | Improved engine logging to note ROLLBACK and COMMIT which is logged while the DBAPI driver is in AUTOCOMMIT mode. These ROLLBACK/COMMIT are library level and do not have any effect when AUTOCOMMIT is in effect, however it's still worthwhile to log as these indicate where SQLAlchemy sees the "transaction" demarcation. Fixes: #6002 Change-Id: I723636515193e0addc86dd0a3132bc23deadb81b
* Implement per-connection logging tokenMike Bayer2021-02-031-9/+52
| | | | | | | | | | | | | | | Added new execution option :paramref:`_engine.Connection.execution_options.logging_token`. This option will add an additional per-message token to log messages generated by the :class:`_engine.Connection` as it executes statements. This token is not part of the logger name itself (that part can be affected using the existing :paramref:`_sa.create_engine.logging_name` parameter), so is appropriate for ad-hoc connection use without the side effect of creating many new loggers. The option can be set at the level of :class:`_engine.Connection` or :class:`_engine.Engine`. Fixes: #5911 Change-Id: Iec9c39b868b3578fcedc1c094dace5b6f64bacea
* Guard against re-entrant autobegin in Core, ORMMike Bayer2021-01-151-1/+2
| | | | | | | | | | | | | | | | | | | | Fixed bug in "future" version of :class:`.Engine` where emitting SQL during the :meth:`.EngineEvents.do_begin` event hook would cause a re-entrant condition due to autobegin, including the recipe documented for SQLite to allow for savepoints and serializable isolation support. Fixed issue in new :class:`_orm.Session` similar to that of the :class:`_engine.Connection` where the new "autobegin" logic could be tripped into a re-entrant state if SQL were executed within the :meth:`.SessionEvents.after_transaction_create` event hook. Also repair the new "testing_engine" pytest fixture to set up for "future" engine appropriately, which wasn't working leading to the test_execute.py tests not using the future engine since recent f1e96cb0874927a475d0c11139. Fixes: #5845 Change-Id: Ib2432d8c8bd753e24be60720ec47affb2df15a4a
* reinvent xdist hooks in terms of pytest fixturesMike Bayer2021-01-131-8/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* happy new yearMike Bayer2021-01-041-1/+1
| | | | Change-Id: Ic5bb19ca8be3cb47c95a0d3315d84cb484bac47c
* Emit 2.0 deprecation warning for sub-transactionsMike Bayer2020-12-141-0/+10
| | | | | | | | The nesting pattern will be removed in 2.0, so the use of the MarkerTransaction should emit a 2.0 deprecation warning unconditionally. Change-Id: I96aed22c4e5db9b59e9b28a7f2d1283cd99a9cb6
* correct for "autocommit" deprecation warningMike Bayer2020-12-111-3/+13
| | | | | | | | | | | | Ensure no autocommit warnings occur internally or within tests. Also includes fixes for SQL Server full text tests which apparently have not been working at all for a long time, as it used long removed APIs. CI has not had fulltext running for some years and is now installed. Change-Id: Id806e1856c9da9f0a9eac88cebc7a94ecc95eb96
* Genericize setinputsizes and support pyodbcMike Bayer2020-10-161-0/+3
| | | | | | | | | | | | Reworked the "setinputsizes()" set of dialect hooks to be correctly extensible for any arbirary DBAPI, by allowing dialects individual hooks that may invoke cursor.setinputsizes() in the appropriate style for that DBAPI. In particular this is intended to support pyodbc's style of usage which is fundamentally different from that of cx_Oracle. Added support for pyodbc. Fixes: #5649 Change-Id: I9f1794f8368bf3663a286932cfe3992dae244a10
* generalize scoped_session proxying and apply to asyncio elementsMike Bayer2020-10-101-11/+19
| | | | | | | | | | | | | | | | | | | | Reworked the proxy creation used by scoped_session() to be based on fully copied code with augmented docstrings and moved it into langhelpers. asyncio session, engine, connection can now take advantage of it so that all non-async methods are availble. Overall implementation of most important accessors / methods on AsyncConnection, etc. , including awaitable versions of invalidate, execution_options, etc. In order to support an event dispatcher on the async classes while still allowing them to hold __slots__, make some adjustments to the event system to allow that to be present, at least rudimentally. Fixes: #5628 Change-Id: I5eb6929fc1e4fdac99e4b767dcfd49672d56e2b2
* upgrade to black 20.8b1Mike Bayer2020-09-281-9/+9
| | | | | | | 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
* new docs WIPMike Bayer2020-09-241-3/+3
| | | | | | | | | | | | | | | This WIP is part of the final push for 1.4's docs to fully "2.0-ize" what we can, and have it all ready. So far this includes a rewrite of the 2.0 migration, set up for the 1.4 /2.0 docs style, and a total redesign of the index page using a new flex layout in zzzeeksphinx. It also reworks some of the API reference sections to have more subheaders. zzzeeksphinx is also enhanced to provide automatic summaries for all api doc section. Change-Id: I01d360cb9c8749520246b96ee6496143c6037918
* Create a framework to allow all SQLALCHEMY_WARN_20 to passMike Bayer2020-09-161-0/+1
| | | | | | | | | | | | | | | | | | | | | As the test suite has widespread use of many patterns that are deprecated, enable SQLALCHEMY_WARN_20 globally for the test suite but then break the warnings filter out into a whole list of all the individual warnings we are looking for. this way individual changesets can target a specific class of warning, as many of these warnings will indivdidually affect dozens of files and potentially hundreds of lines of code. Many warnings are also resolved here as this patch started out that way. From this point forward there should be changesets that target a subset of the warnings at a time. For expediency, updates some migration 2.0 docs for ORM as well. Change-Id: I98b8defdf7c37b818b3824d02f7668e3f5f31c94
* Merge "Update session.execute() and related documentation"mike bayer2020-09-131-6/+6
|\
| * Update session.execute() and related documentationMike Bayer2020-09-131-6/+6
| | | | | | | | | | | | | | | | | | | | The docs here were completely out of date and referred to behaviors that are no longer true, behaviors that are deprecated, etc. For the moment, take out all the verbiage so that nothing incorrect is present. New ORM documentation will need to be constructed to support this statement. Change-Id: I4782aebb6443ceb68752c3b52b574fd30658ebc9
* | Deprecate engine-wise ss cursors; repair mariadbconnectorMike Bayer2020-09-131-2/+7
|/ | | | | | | | | | | | | | | | | | | The server_side_cursors engine-wide feature relies upon regexp parsing of statements a well as general guessing as to when the feature should be used. This is not within the 2.0 way of doing things and should be removed. Additionally, mariadbconnector defaults to unbuffered cursors; add new cursor hooks so that mariadbconnector can specify buffered or unbuffered cursors without too much difficulty. This will also correctly default mariadbconnector to buffered cursors which should repair the segfaults we've been getting. Try to restore the assert_raises that was removed in 5b6dfc0c38bf1f01da4b8 to see if mariadbconnector segfaults are resolved. Change-Id: I77f1c972c742e40694972f578140bb0cac8c39eb
* Emit v2.0 deprecation warning for "implicit autocommit"Gord Thompson2020-08-281-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | "Implicit autocommit", which is the COMMIT that occurs when a DML or DDL statement is emitted on a connection, is deprecated and won't be part of SQLAlchemy 2.0. A 2.0-style warning is emitted when autocommit takes effect, so that the calling code may be adjusted to use an explicit transaction. As part of this change, DDL methods such as :meth:`_schema.MetaData.create_all` when used against a :class:`_engine.Engine` or :class:`_engine.Connection` will run the operation in a BEGIN block if one is not started already. The MySQL and MariaDB dialects now query from the information_schema.tables system view in order to determine if a particular table exists or not. Previously, the "DESCRIBE" command was used with an exception catch to detect non-existent, which would have the undesirable effect of emitting a ROLLBACK on the connection. There appeared to be legacy encoding issues which prevented the use of "SHOW TABLES", for this, but as MySQL support is now at 5.0.2 or above due to :ticket:`4189`, the information_schema tables are now available in all cases. Fixes: #4846 Change-Id: I733a7e0e17477a63607fb9931c87c393bbd7ac57
* make URL immutableMike Bayer2020-08-251-1/+1
| | | | | | | | | | | | | | it's not really correct that URL is mutable and doesn't do any argument checking. propose replacing it with an immutable named tuple with rich copy-and-mutate methods. At the moment this makes a hard change to the CreateEnginePlugin docs that previously recommended url.query.pop(). I can't find any plugins on github other than my own that are using this feature, so see if we can just make a hard change on this one. Fixes: #5526 Change-Id: I28a0a471d80792fa8c28f4fa573d6352966a4a79
* normalize execute style for events, 2.0Mike Bayer2020-08-201-50/+137
| | | | | | | | | | | | | | | The _execute_20 and exec_driver_sql methods should wrap up the parameters so that they represent the single list / single dictionary style of invocation into the legacy methods. then the before_ after_ execute event handlers should be receiving the parameter dictionary as a single dictionary. this requires that we break out distill_params to work differently if event handlers are present. additionally, add deprecation warnings for old argument passing styles. Change-Id: I97cb4d06adfcc6b889f10d01cc7775925cffb116
* Implement rudimentary asyncio support w/ asyncpgMike Bayer2020-08-131-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | Using the approach introduced at https://gist.github.com/zzzeek/6287e28054d3baddc07fa21a7227904e We can now create asyncio endpoints that are then handled in "implicit IO" form within the majority of the Core internals. Then coroutines are re-exposed at the point at which we call into asyncpg methods. Patch includes: * asyncpg dialect * asyncio package * engine, result, ORM session classes * new test fixtures, tests * some work with pep-484 and a short plugin for the pyannotate package, which seems to have so-so results Change-Id: Idbcc0eff72c4cad572914acdd6f40ddb1aef1a7d Fixes: #3414
* more docs for autocommit isolation levelMike Bayer2020-07-121-10/+8
| | | | | | | | this concept is not clear that we offer real DBAPI autocommit everywhere. backport 1.3 with edits as well Change-Id: I2e8328b7fb6e1cdc5453ab29c94276f60c7ca149
* Convert remaining ORM APIs to support 2.0 styleMike Bayer2020-07-111-0/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is kind of a mixed bag of all kinds to help get us to 1.4 betas. The documentation stuff is a work in progress. Lots of other relatively small changes to APIs and things. More commits will follow to continue improving the documentation and transitioning to the 1.4/2.0 hybrid documentation. In particular some refinements to Session usage models so that it can match Engine's scoping / transactional patterns, and a decision to start moving away from "subtransactions" completely. * add select().from_statement() to produce FromStatement in an ORM context * begin referring to select() that has "plugins" for the few edge cases where select() will have ORM-only behaviors * convert dynamic.AppenderQuery to its own object that can use select(), though at the moment it uses Query to support legacy join calling forms. * custom query classes for AppenderQuery are replaced by do_orm_execute() hooks for custom actions, a separate gerrit will document this * add Session.get() to replace query.get() * Deprecate session.begin->subtransaction. propose within the test suite a hypothetical recipe for apps that rely on this pattern * introduce Session construction level context manager, sessionmaker context manager, rewrite the whole top of the session_transaction.rst documentation. Establish context manager patterns for Session that are identical to engine * ensure same begin_nested() / commit() behavior as engine * devise all new "join into an external transaction" recipe, add test support for it, add rules into Session so it just works, write new docs. need to ensure this doesn't break anything * vastly reduce the verbosity of lots of session docs as I dont think people read this stuff and it's difficult to keep current in any case * constructs like case(), with_only_columns() really need to move to *columns, add a coercion rule to just change these. * docs need changes everywhere I look. in_() is not in the Core tutorial? how do people even know about it? Remove tons of cruft from Select docs, etc. * build a system for common ORM options like populate_existing and autoflush to populate from execution options. * others? Change-Id: Ia4bea0f804250e54d90b3884cf8aab8b66b82ecf
* Add future=True to create_engine/Session; unify select()Mike Bayer2020-07-081-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Several weeks of using the future_select() construct has led to the proposal there be just one select() construct again which features the new join() method, and otherwise accepts both the 1.x and 2.x argument styles. This would make migration simpler and reduce confusion. However, confusion may be increased by the fact that select().join() is different Current thinking is we may be better off with a few hard behavioral changes to old and relatively unknown APIs rather than trying to play both sides within two extremely similar but subtly different APIs. At the moment, the .join() thing seems to be the only behavioral change that occurs without the user taking any explicit steps. Session.execute() will still behave the old way as we are adding a future flag. This change also adds the "future" flag to Session() and session.execute(), so that interpretation of the incoming statement, as well as that the new style result is returned, does not occur for existing applications unless they add the use of this flag. The change in general is moving the "removed in 2.0" system further along where we want the test suite to fully pass even if the SQLALCHEMY_WARN_20 flag is set. Get many tests to pass when SQLALCHEMY_WARN_20 is set; this should be ongoing after this patch merges. Improve the RemovedIn20 warning; these are all deprecated "since" 1.4, so ensure that's what the messages read. Make sure the inforamtion link is on all warnings. Add deprecation warnings for parameters present and add warnings to all FromClause.select() types of methods. Fixes: #5379 Fixes: #5284 Change-Id: I765a0b912b3dcd0e995426427d8bb7997cbffd51 References: #5159
* introduce deferred lambdasMike Bayer2020-07-031-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The coercions system allows us to add in lambdas as arguments to Core and ORM elements without changing them at all. By allowing the lambda to produce a deterministic cache key where we can also cheat and yank out literal parameters means we can move towards having 90% of "baked" functionality in a clearer way right in Core / ORM. As a second step, we can have whole statements inside the lambda, and can then add generation with __add__(), so then we have 100% of "baked" functionality with full support of ad-hoc literal values. Adds some more short_selects tests for the moment for comparison. Other tweaks inside cache key generation as we're trying to approach a certain level of performance such that we can remove the use of "baked" from the loader strategies. As we have not yet closed #4639, however the caching feature has been fully integrated as of b0cfa7379cf8513a821a3dbe3028c4965d9f85bd, we will also add complete caching documentation here and close that issue as well. Closes: #4639 Fixes: #5380 Change-Id: If91f61527236fd4d7ae3cad1f24c38be921c90ba
* Merge "Fix a wide variety of typos and broken links"mike bayer2020-06-261-6/+6
|\
| * Fix a wide variety of typos and broken linksaplatkouski2020-06-251-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | Note the PR has a few remaining doc linking issues listed in the comment that must be addressed separately. Signed-off-by: aplatkouski <5857672+aplatkouski@users.noreply.github.com> Closes: #5371 Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/5371 Pull-request-sha: 7e7d233cf3a0c66980c27db0fcdb3c7d93bc2510 Change-Id: I9c36e8d8804483950db4b42c38ee456e384c59e3
* | Default psycopg2 executemany mode to "values_only"Mike Bayer2020-06-251-3/+3
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The psycopg2 dialect now defaults to using the very performant ``execute_values()`` psycopg2 extension for compiled INSERT statements, and also impements RETURNING support when this extension is used. This allows INSERT statements that even include an autoincremented SERIAL or IDENTITY value to run very fast while still being able to return the newly generated primary key values. The ORM will then integrate this new feature in a separate change. Implements RETURNING for insert with executemany Adds support to return_defaults() mode and inserted_primary_key to support mutiple INSERTed rows, via return_defauls_rows and inserted_primary_key_rows accessors. within default execution context, new cached compiler getters are used to fetch primary keys from rows inserted_primary_key now returns a plain tuple. this is not yet a row-like object however this can be added. Adds distinct "values_only" and "batch" modes, as "values" has a lot of benefits but "batch" breaks cursor.rowcount psycopg2 minimum version 2.7 so we can remove the large number of checks for very old versions of psycopg2 simplify tests to no longer distinguish between native and non-native json Fixes: #5401 Change-Id: Ic08fd3423d4c5d16ca50994460c0c234868bd61c
* Warn when transaction context manager ends on inactive transactionMike Bayer2020-06-121-3/+6
| | | | | | | | | | if .rollback() or .commit() is called inside the transaction context manager, the transaction object is deactivated. the context manager continues but will not be able to correctly fulfill it's closing state. Ensure a warning is emitted when this happens. Change-Id: I8fc3a73f7c21575dda5bcbd6fb74ddb679771630
* Turn on caching everywhere, add loggingMike Bayer2020-06-101-56/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A variety of caching issues found by running all tests with statement caching turned on. The cache system now has a more conservative approach where any subclass of a SQL element will by default invalidate the cache key unless it adds the flag inherit_cache=True at the class level, or if it implements its own caching. Add working caching to a few elements that were omitted previously; fix some caching implementations to suit lesser used edge cases such as json casts and array slices. Refine the way BaseCursorResult and CursorMetaData interact with caching; to suit cases like Alembic modifying table structures, don't cache the cursor metadata if it were created against a cursor.description using non-positional matching, e.g. "select *". if a table re-ordered its columns or added/removed, now that data is obsolete. Additionally we have to adapt the cursor metadata _keymap regardless of if we just processed cursor.description, because if we ran against a cached SQLCompiler we won't have the right columns in _keymap. Other refinements to how and when we do this adaption as some weird cases were exposed in the Postgresql dialect, a text() construct that names just one column that is not actually in the statement. Fixed that also as it looks like a cut-and-paste artifact that doesn't actually affect anything. Various issues with re-use of compiled result maps and cursor metadata in conjunction with tables being changed, such as change in order of columns. mappers can be cleared but the class remains, meaning a mapper has to use itself as the cache key not the class. lots of bound parameter / literal issues, due to Alembic creating a straight subclass of bindparam that renders inline directly. While we can update Alembic to not do this, we have to assume other people might be doing this, so bindparam() implements the inherit_cache=True logic as well that was a bit involved. turn on cache stats in logging. Includes a fix to subqueryloader which moves all setup to the create_row_processor() phase and elminates any storage within the compiled context. This includes some changes to create_row_processor() signature and a revising of the technique used to determine if the loader can participate in polymorphic queries, which is also applied to selectinloading. DML update.values() and ordered_values() now coerces the keys as we have tests that pass an arbitrary class here which only includes __clause_element__(), so the key can't be cached unless it is coerced. this in turn changed how composite attributes support bulk update to use the standard approach of ClauseElement with annotations that are parsed in the ORM context. memory profiling successfully caught that the Session from Query was getting passed into _statement_20() so that was a big win for that test suite. Apparently Compiler had .execute() and .scalar() methods stuck on it, these date back to version 0.4 and there was a single test in the PostgreSQL dialect tests that exercised it for no apparent reason. Removed these methods as well as the concept of a Compiler holding onto a "bind". Fixes: #5386 Change-Id: I990b43aab96b42665af1b2187ad6020bee778784
* callcount reductions and refinement for cached queriesMike Bayer2020-05-281-54/+105
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit includes that we've removed the "_orm_query" attribute from compile state as well as query context. The attribute created reference cycles and also added method call overhead. As part of this change, the interface for ORMExecuteState changes a bit, as well as the interface for the horizontal sharding extension which now deprecates the "query_chooser" callable in favor of "execute_chooser", which receives the contextual object. This will also work more nicely when we implement the new execution path for bulk updates and deletes. Pre-merge execution options for statement, connection, arguments all up front in Connection. that way they can be passed to the before_execute / after_execute events, and the ExecutionContext doesn't have to merge as second time. Core execute is pretty close to 1.3 now. baked wasn't using the new one()/first()/one_or_none() methods, fixed that. Convert non-buffered cursor strategy to be a stateless singleton. inline all the paths by which the strategy gets chosen, oracle and SQL Server dialects make use of the already-invoked post_exec() hook to establish the alternate strategies, and this is actually much nicer than it was before. Add caching to mapper instance processor for getters. Identified a reference cycle per query that was showing up as a lot of gc cleanup, fixed that. After all that, performance not budging much. Even test_baked_query now runs with significantly fewer function calls than 1.3, still 40% slower. Basically something about the new patterns just makes this slower and while I've walked a whole bunch of them back, it hardly makes a dent. that said, the performance issues are relatively small, in the 20-40% time increase range, and the new caching feature does provide for regular ORM and Core queries that are cached, and they are faster than non-cached. Change-Id: I7b0b0d8ca550c05f79e82f75cd8eff0bbfade053
* Convert execution to move through SessionMike Bayer2020-05-251-29/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch replaces the ORM execution flow with a single pathway through Session.execute() for all queries, including Core and ORM. Currently included is full support for ORM Query, Query.from_statement(), select(), as well as the baked query and horizontal shard systems. Initial changes have also been made to the dogpile caching example, which like baked query makes use of a new ORM-specific execution hook that replaces the use of both QueryEvents.before_compile() as well as Query._execute_and_instances() as the central ORM interception hooks. select() and Query() constructs alike can be passed to Session.execute() where they will return ORM results in a Results object. This API is currently used internally by Query. Full support for Session.execute()->results to behave in a fully 2.0 fashion will be in later changesets. bulk update/delete with ORM support will also be delivered via the update() and delete() constructs, however these have not yet been adapted to the new system and may follow in a subsequent update. Performance is also beginning to lag as of this commit and some previous ones. It is hoped that a few central functions such as the coercions functions can be rewritten in C to re-gain performance. Additionally, query caching is now available and some subsequent patches will attempt to cache more of the per-execution work from the ORM layer, e.g. column getters and adapters. This patch also contains initial "turn on" of the caching system enginewide via the query_cache_size parameter to create_engine(). Still defaulting at zero for "no caching". The caching system still needs adjustments in order to gain adequate performance. Change-Id: I047a7ebb26aa85dc01f6789fac2bff561dcd555d
* Unify Query and select() , move all processing to compile phaseMike Bayer2020-05-241-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | Convert Query to do virtually all compile state computation in the _compile_context() phase, and organize it all such that a plain select() construct may also be used as the source of information in order to generate ORM query state. This makes it such that Query is not needed except for its additional methods like from_self() which are all to be deprecated. The construction of ORM state will occur beyond the caching boundary when the new execution model is integrated. future select() gains a working join() and filter_by() method. as we continue to rebase and merge each commit in the steps, callcounts continue to bump around. will have to look at the final result when it's all in. References: #5159 References: #4705 References: #4639 References: #4871 References: #5010 Change-Id: I19e05b3424b07114cce6c439b05198ac47f7ac10
* Structural / performance refinementsMike Bayer2020-05-221-13/+17
| | | | | | | | | | | | * state connection schema_translate_map entirely in terms of execution options, support for per-execution options as well * use slots for role impls, remove superclass of the roles themselves as this is not needed * tighten loop in resolve, might become a C function Change-Id: Ib98ac9b65022fbf976e49c6060e4c37573528c5f
* Performance fixes for new result setMike Bayer2020-05-211-1/+3
| | | | | | | | | | | A few small mistakes led to huge callcounts. Additionally, the warn-on-get behavior which is attempting to warn for deprecated access in SQLAlchemy 2.0 is very expensive; it's not clear if its feasible to have this warning or to somehow alter how it works. Fixes: #5340 Change-Id: I73bdd2d7b6f1b25cc0222accabd585cf761a5af4