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* Ensure _distinct_on removed within from_selectableMike Bayer2020-07-201-0/+1
| | | | | Fixes: #5469 Change-Id: I85498d3380c2efb595782d2ba92cfd692c3efc48
* Convert remaining ORM APIs to support 2.0 styleMike Bayer2020-07-111-376/+70
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 Bayer2020-07-081-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 Bayer2020-07-031-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Fix a wide variety of typos and broken linksaplatkouski2020-06-251-22/+23
| | | | | | | | | | | | 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
* Merge "perf tweaks"mike bayer2020-06-191-2/+1
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| * perf tweaksMike Bayer2020-06-191-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | - avoid abc checks in distill_20 - ColumnEntity subclasses are unique to their compile state and have no querycontext specific state. They can do a simple memoize of their fetch_column without using attributes, and they can memoize their _getter() too so that it goes into the cache, just like instance_processor() does. - unify ORMColumnEntity and RawColumnEntity for the row processor part, add some test coverage for the case where it is used in a from_statement - do a faster generate if there are no memoized entries - query._params is always immutabledict Change-Id: I1e2dfe607a1749b5b434fc11f9348ee631501dfa
* | Add note indicating order of join() calls are importantMike Bayer2020-06-191-0/+13
|/ | | | | Fixes: #5406 Change-Id: I186792b32bd156d5ddf256dcd018af32ad5b515e
* Turn on caching everywhere, add loggingMike Bayer2020-06-101-3/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Convert bulk update/delete to new execution modelMike Bayer2020-06-061-17/+98
| | | | | | | | | | | | | | | This reorganizes the BulkUD model in sqlalchemy.orm.persistence to be based on the CompileState concept and to allow plain update() / delete() to be passed to session.execute() where the ORM synchronize session logic will take place. Also gets "synchronize_session='fetch'" working with horizontal sharding. Adding a few more result.scalar_one() types of methods as scalar_one() seems like what is normally desired. Fixes: #5160 Change-Id: I8001ebdad089da34119eb459709731ba6c0ba975
* Improve rendering of core statements w/ ORM elementsMike Bayer2020-05-311-18/+79
| | | | | | | | | | | | | | | | | | | | This patch contains a variety of ORM and expression layer tweaks to support ORM constructs in select() statements, without the 1.3.x requiremnt in Query that a full _compile_context() + new select() is needed in order to get a working statement object. Includes such tweaks as the ability to implement aliased class of an aliased class, as we are looking to fully support ACs against subqueries, as well as the ability to access anonymously-labeled ColumnProperty expressions within subqueries by naming the ".key" of the label after the property key. Some tuning to query.join() as well as ORMJoin internals to allow things to work more smoothly. Change-Id: Id810f485c5f7ed971529489b84694e02a3356d6d
* callcount reductions and refinement for cached queriesMike Bayer2020-05-281-65/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 Bayer2020-05-251-97/+215
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 Bayer2020-05-241-2208/+603
| | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Merge "Improve error message when using :meth:`_query.Query.filter_by` in a ↵mike bayer2020-05-231-1/+10
|\ | | | | | | query where the first entity is not a mapped class."
| * Improve error message when using :meth:`_query.Query.filter_by` inFederico Caselli2020-05-151-1/+10
| | | | | | | | | | | | | | a query where the first entity is not a mapped class. Fixes: #5260 Change-Id: I18cfccc0f3e587cb3df3e1f5f23b6885d5f2f466
* | Merge "fix typo in reference documentation"mike bayer2020-05-231-1/+1
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| * | fix typo in reference documentationFederico Caselli2020-05-231-1/+1
| | | | | | | | | | | | Change-Id: I5720635863f0d8a8ebfa4ddc51008bb93c1067b4
* | | Add immutabledict C codeMike Bayer2020-05-231-4/+4
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* | Performance fixes for new result setMike Bayer2020-05-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | 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
* | Streamline visitors.iterateMike Bayer2020-05-181-4/+1
|/ | | | | | | | | | | | | | | | | | | | This method might be used more significantly in the ORM refactor, so further refine it. * all get_children() methods now work entirely based on iterators. Basically only select() was sensitive to this anymore and it now chains the iterators together * remove all kinds of flags like column_collections, schema_visitor that apparently aren't used anymore. * remove the "depthfirst" visitors as these don't seem to be used either. * make sure select() yields its columns first as these will be used to determine the current mapper. Change-Id: I05273a2d5306a57c2d1b0979050748cf3ac964bf
* Consider aliased=True, from_joinpoint as legacyMike Bayer2020-05-041-163/+172
| | | | | | | | | | | | | | | | For a 1.4 / 1.3 merge, rewrite the documentation for Query.join() to indicate calling forms that are now considered legacy, including the use of strings in join(), sending a series of join paths in one call, and using the aliased=True flag. update the elementtree examples as well to use aliased() (they are much simpler to understand this way too) and update other links. Also improve docs for aliased() and some other ORM targets such as PropComparator. Change-Id: I636e3a9130dc5509e51c2cf60a52f38fcadffbc6 References: #4705
* Integrate new Result into ORM queryMike Bayer2020-05-021-40/+30
| | | | | | | | | | | | | | | | | | | | | | | | The next step in the 2.0 ORM changes is to have the ORM integrate with the new Result object fully. this patch uses Result to represent ORM objects rather than lists. public API to get at this Result is not added yet. dogpile.cache and horizontal sharding recipe/extensions have small adjustments to accommodate this change. Callcounts have fluctuated, some slightly better and some slightly worse. A few have gone up by a bit, however as the codebase is still in flux it is anticipated there will be some performance gains later on as ORM fetching is refined to no longer need to accommodate for extensive aliasing. The addition of caching will then change the entire story. References: #5087 References: #4395 Change-Id: If1a23824ffb77d8d58cf2338cf35dd6b5963b17f
* Documentation updates for ResultProxy -> ResultMike Bayer2020-05-011-1/+1
| | | | | | | | | This is based off of I8091919d45421e3f53029b8660427f844fee0228 and includes all documentation-only changes as a separate merge, once the parent is merged. Change-Id: I711adea23df0f9f0b1fe7c76210bd2de6d31842d
* Propose Result as immediate replacement for ResultProxyMike Bayer2020-05-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As progress is made on the _future.Result, including breaking it out such that DBAPI behaviors are local to specific implementations, it becomes apparent that the Result object is a functional superset of ResultProxy and that basic operations like fetchone(), fetchall(), and fetchmany() behave pretty much exactly the same way on the new object. Reorganize things so that ResultProxy is now referred to as LegacyCursorResult, which subclasses CursorResult that represents the DBAPI-cursor version of Result, making use of a multiple inheritance pattern so that the functionality of Result is also available in non-DBAPI contexts, as will be necessary for some ORM patterns. Additionally propose the composition system for Result that will form the basis for ORM-alternative result systems such as horizontal sharding and dogpile cache. As ORM results will soon be coming directly from instances of Result, these extensions will instead build their own ResultFetchStrategies that perform the special steps to create composed or cached result sets. Also considering at the moment not emitting deprecation warnings for fetchXYZ() methods; the immediate issue is Keystone tests are calling upon it, but as the implementations here are proving to be not in any kind of conflict with how Result works, there's not too much issue leaving them around and deprecating at some later point. References: #5087 References: #4395 Fixes: #4959 Change-Id: I8091919d45421e3f53029b8660427f844fee0228
* Restore a line break that is needed for a clean mergeMike Bayer2020-04-291-0/+1
| | | | Change-Id: Ib433920080ba159a1478c48d2f837bc71bf5bbbc
* Alias the onclause if ORM join is to same polymorphic selectableMike Bayer2020-04-271-1/+0
| | | | | | | | | | Fixed bug where using :func:`.with_polymorphic` as the target of a join via :meth:`.RelationshipComparator.of_type` on a mapper that already has a subquery-based with_polymorphic setting that's equivalent to the one requested would not correctly alias the ON clause in the join. Fixes: #5288 Change-Id: I0212a990ee67a344c87fe21833bf47fdb72ca0cc
* Deprecate ``DISTINCT ON`` when not targeting PostgreSQLFederico Caselli2020-04-201-0/+3
| | | | | | | | | Deprecate usage of ``DISTINCT ON`` in dialect other than PostgreSQL. Previously this was silently ignored. Deprecate old usage of string distinct in MySQL dialect Fixes: #4002 Change-Id: I38fc64aef75e77748083c11d388ec831f161c9c9
* Set up absolute references for create_engine and relatedMike Bayer2020-04-141-1/+1
| | | | | | | includes more replacements for create_engine(), Connection, disambiguation of Result from future/baked Change-Id: Icb60a79ee7a6c45ea9056c211ffd1be110da3b5e
* Run search and replace of symbolic module namesMike Bayer2020-04-141-223/+300
| | | | | | | | Replaces a wide array of Sphinx-relative doc references with an abbreviated absolute form now supported by zzzeeksphinx. Change-Id: I94bffcc3f37885ffdde6238767224296339698a2
* Remove code deprecated before version 1.1Federico Caselli2020-04-091-14/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Remove deprecated method ``get_primary_keys` in the :class:`.Dialect` and :class:`.Inspector` classes. - Remove deprecated event ``dbapi_error`` and the method ``ConnectionEvents.dbapi_error`. - Remove support for deprecated engine URLs of the form ``postgres://``. - Remove deprecated dialect ``mysql+gaerdbms``. - Remove deprecated parameter ``quoting`` from :class:`.mysql.ENUM` and :class:`.mysql.SET` in the ``mysql`` dialect. - Remove deprecated function ``comparable_property``. and function ``comparable_using`` in the declarative extension. - Remove deprecated function ``compile_mappers``. - Remove deprecated method ``collection.linker``. - Remove deprecated method ``Session.prune`` and parameter ``Session.weak_identity_map``. This change also removes the class ``StrongInstanceDict``. - Remove deprecated parameter ``mapper.order_by``. - Remove deprecated parameter ``Session._enable_transaction_accounting`. - Remove deprecated parameter ``Session.is_modified.passive``. - Remove deprecated class ``Binary``. Please use :class:`.LargeBinary`. - Remove deprecated methods ``Compiled.compile``, ``ClauseElement.__and__`` and ``ClauseElement.__or__`` and attribute ``Over.func``. - Remove deprecated ``FromClause.count`` method. - Remove deprecated parameter ``Table.useexisting``. - Remove deprecated parameters ``text.bindparams`` and ``text.typemap``. - Remove boolean support for the ``passive`` parameter in ``get_history``. - Remove deprecated ``adapt_operator`` in ``UserDefinedType.Comparator``. Fixes: #4643 Change-Id: Idcd390c77bf7b0e9957907716993bdaa3f1a1763
* Run autoflush for column attribute load operationsMike Bayer2020-04-031-1/+1
| | | | | | | | | | | | | | | | | The "autoflush" behavior of :class:`.Query` will now trigger for nearly all ORM level attribute load operations, including when a deferred column is loaded as well as when an expired column is loaded. Previously, autoflush on load of expired or unloaded attributes was limited to relationship-bound attributes only. However, this led to the issue where column-based attributes that also depended on other rows, or even other columns in the same row, in order to express the correct value, would show an effectively stale value when accessed as there could be pending changes in the session left to be flushed. Autoflush is now disabled only in some cases where attributes are being unexpired in the context of a history operation. Fixes: #5226 Change-Id: Ibd965b30918cd273ae020411a704bf2bb1891f59
* Add a third labeling mode for SELECT statementsMike Bayer2020-03-291-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Enhanced the disambiguating labels feature of the :func:`~.sql.expression.select` construct such that when a select statement is used in a subquery, repeated column names from different tables are now automatically labeled with a unique label name, without the need to use the full "apply_labels()" feature that conbines tablename plus column name. The disambigated labels are available as plain string keys in the .c collection of the subquery, and most importantly the feature allows an ORM :func:`.orm.aliased` construct against the combination of an entity and an arbitrary subquery to work correctly, targeting the correct columns despite same-named columns in the source tables, without the need for an "apply labels" warning. The existing labeling style is now called LABEL_STYLE_TABLENAME_PLUS_COL. This labeling style will remain used throughout the ORM as has been the case for over a decade, however, the new disambiguation scheme could theoretically replace this scheme entirely. The new scheme would dramatically alter how SQL looks when rendered from the ORM to be more succinct but arguably harder to read. The tablename_columnname scheme used by Join.c is unaffected here, as that's still hardcoded to that scheme. Fixes: #5221 Change-Id: Ib47d9e0f35046b3afc77bef6e65709b93d0c3026
* Merge "Correct ambiguous func / class links"mike bayer2020-03-251-4/+4
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| * Correct ambiguous func / class linksMike Bayer2020-03-251-4/+4
| | | | | | | | | | | | | | | | | | :func:`.sql.expression.select`, :func:`.sql.expression.insert` and :class:`.sql.expression.Insert` were hitting many ambiguous symbol errors, due to future.select, as well as the PG/MySQL variants of Insert. Change-Id: Iac862bfc172a7f7f0cbba5353a83dc203bed376c
* | Deprecate add of columns in order by with distinctFederico Caselli2020-03-251-12/+24
|/ | | | | | | Deprecate automatic addition of order by column in a query with a distinct Fixes: #5134 Change-Id: I467a39379c496be7e84a05f11ba9f8ca2bcc6e32
* Remove deprecated elements from selectable.py; remove lockmodeMike Bayer2020-03-231-59/+1
| | | | | | | | | | | | | Removed autocommit and legacy "for update" / "lockmode" elements from selectable.py / query.py. lockmode was removed from selectable in 693938dd6fb2f3ee3e031aed4c62355ac97f3ceb however was not removed from the ORM. Also removes the ignore_nonexistent_tables option on join(). Change-Id: I0cfcf9e6a8d4ef6432c9e25ef75173b3b3f5fd87 Partially-fixes: #4643
* Test instance for matching class hierarchy on get_from_identityMike Bayer2020-03-221-0/+2
| | | | | | | | | | | Fixed issue where a lazyload that uses session-local "get" against a target many-to-one relationship where an object with the correct primary key is present, however it's an instance of a sibling class, does not correctly return None as is the case when the lazy loader actually emits a load for that row. Fixes: #5210 Change-Id: I89f9946cfeba61d89a272435f76a5a082b1da30c
* Reword implicit left join error; ensure deterministic FROM for columnsMike Bayer2020-03-101-10/+18
| | | | | | | | | | | | Adjusted the error message emitted by :meth:`.Query.join` when a left hand side can't be located that the :meth:`.Query.select_from` method is the best way to resolve the issue. Also, within the 1.3 series, used a deterministic ordering when determining the FROM clause from a given column entity passed to :class:`.Query` so that the same expression is determined each time. Fixes: #5194 Change-Id: I2e4065fd31e98c57edf2f11d5e831be44d2c1ea2
* Simplified module pre-loading strategy and made it linter friendlyFederico Caselli2020-03-071-3/+4
| | | | | | | | | | | | | | | | | Introduced a modules registry to register modules that should be lazily loaded in the package init. This ensures that they are in the system module cache, avoiding potential thread safety issues as when importing them directly in the function that uses them. The module registry is used to obtain these modules directly, ensuring that the all the lazily loaded modules are resolved at the proper time This replaces dependency_for decorator and the dependencies decorator logic, removing the need to pass the resolved modules as arguments of the decodated functions and removes possible errors caused by linters. Fixes: #4689 Fixes: #4656 Change-Id: I2e291eba4297867fc0ddb5d875b9f7af34751d01
* Don't import provision.py unconditionallyMike Bayer2020-03-031-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | Removed the imports for provision.py from each dialect and instead added a call in the central provision.py to a new dialect level method load_provisioning(). The provisioning registry works in the same way, so an existing dialect that is using the provision.py system right now by importing it as part of the package will still continue to function. However, to avoid pulling in the testing package when the dialect is used in a non-testing context, the new hook may be used. Also removed a module-level dependency of the testing framework on the orm package. Revised an internal change to the test system added as a result of :ticket:`5085` where a testing-related module per dialect would be loaded unconditionally upon making use of that dialect, pulling in SQLAlchemy's testing framework as well as the ORM into the module import space. This would only impact initial startup time and memory to a modest extent, however it's best that these additional modules aren't reverse-dependent on straight Core usage. Fixes: #5180 Change-Id: I6355601da5f6f44d85a2bbc3acb5928559942b9c
* Ensure all nested exception throws have a causeMike Bayer2020-03-021-12/+18
| | | | | | | | | | | | | | | 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
* Result initial introductionMike Bayer2020-02-211-6/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This builds on cc718cccc0bf8a01abdf4068c7ea4f3 which moved RowProxy to Row, allowing Row to be more like a named tuple. - KeyedTuple in ORM is replaced with Row - ResultSetMetaData broken out into "simple" and "cursor" versions for ORM and Core, as well as LegacyCursor version. - Row now has _mapping attribute that supplies full mapping behavior. Row and SimpleRow both have named tuple behavior otherwise. LegacyRow has some mapping features on the tuple which emit deprecation warnings (e.g. keys(), values(), etc). the biggest change for mapping->tuple is the behavior of __contains__ which moves from testing of "key in row" to "value in row". - ResultProxy breaks into ResultProxy and FutureResult (interim), the latter has the newer APIs. Made available to dialects using execution options. - internal reflection methods and most tests move off of implicit Row mapping behavior and move to row._mapping, result.mappings() method using future result - a new strategy system for cursor handling replaces the various subclasses of RowProxy - some execution context adjustments. We will leave EC in but refined things like get_result_proxy() and out parameter handling. Dialects for 1.4 will need to adjust from get_result_proxy() to get_result_cursor_strategy(), if they are using this method - out parameter handling now accommodated by get_out_parameter_values() EC method. Oracle changes for this. external dialect for DB2 for example will also need to adjust for this. - deprecate case_insensitive flag for engine / result, this feature is not used mapping-methods on Row are deprecated, and replaced with Row._mapping.<meth>, including: row.keys() -> use row._mapping.keys() row.items() -> use row._mapping.items() row.values() -> use row._mapping.values() key in row -> use key in row._mapping int in row -> use int < len(row) Fixes: #4710 Fixes: #4878 Change-Id: Ieb9085e9bcff564359095b754da9ae0af55679f0
* Create initial future package, RemovedIn20WarningMike Bayer2020-02-121-9/+4
| | | | | | | | | | | | | | | | | Reorganization of Select() is the first major element of the 2.0 restructuring. In order to start this we need to first create the new Select constructor and apply legacy elements to the old one. This in turn necessitates starting up the RemovedIn20Warning concept which itself need to refer to "sqlalchemy.future", so begin to establish this basic framework. Additionally, update the DML constructors with the newer no-keyword style. Remove the use of the "pending deprecation" and fix Query.add_column() deprecation which was not acting as deprecated. Fixes: #4845 Fixes: #4648 Change-Id: I0c7a22b2841a985e1c379a0bb6c94089aae6264c
* Raise for unexpected polymorphic identityMike Bayer2020-01-291-4/+4
| | | | | | | | | | | | | | | | | A query that is against an mapped inheritance subclass which also uses :meth:`.Query.select_entity_from` or a similar technique in order to provide an existing subquery to SELECT from, will now raise an error if the given subquery returns entities that do not correspond to the given subclass, that is, they are sibling or superclasses in the same hierarchy. Previously, these would be returned without error. Additionally, if the inheritance mapping is a single-inheritance mapping, the given subquery must apply the appropriate filtering against the polymorphic discriminator column in order to avoid this error; previously, the :class:`.Query` would add this criteria to the outside query however this interferes with some kinds of query that return other kinds of entities as well. Fixes: #5122 Change-Id: I60cf8c1300d5bb279ad99f0f01fefe7e008a159b
* Clarify documentation for lazy_loaded_fromMike Bayer2020-01-221-3/+25
| | | | | | | | | | | This attribute was never available in conjunction with mapper options, and additionally the use of baked queries in the lazy loader strategy prevent this attribute from being reliably available within the before_compile hook unless baked queries are turned off entirely. Fixes: #5109 Change-Id: I5fa12c68463d20475e7470647a784efe846b8af7
* Fix QueryContext ref cycle on joinedloadCarson Ip2020-01-041-1/+1
| | | | | | | | | | | Avoid storing a reference to itself when dealing with create_eager_joins. Also fix a cheating test. Fixes: #5071 Closes: #5072 Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/5072 Pull-request-sha: 75ebaf7c91e96d7567eb5760be713dc134c58763 Change-Id: I511ddc0979b46f7928217347199eca4b1d0b4a49
* happy new yearMike Bayer2020-01-011-1/+1
| | | | Change-Id: I08440dc25e40ea1ccea1778f6ee9e28a00808235
* Merge "Test for short term reference cycles and resolve as many as possible"mike bayer2019-12-311-1/+1
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| * Test for short term reference cycles and resolve as many as possibleMike Bayer2019-12-301-1/+1
| | | | | | | | | | | | | | | | Added test support and repaired a wide variety of unnecessary reference cycles created for short-lived objects, mostly in the area of ORM queries. Fixes: #5056 Change-Id: Ifd93856eba550483f95f9ae63d49f36ab068b85a