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* Further refine labeling for renamed columnsMike Bayer2021-02-121-24/+21
| | | | | | | | | | | | | | | Forked from I22f6cf0f0b3360e55299cdcb2452cead2b2458ea we are attempting to decide the case for columns mapped under a different name. since the .key feature of Column seems to support this fully, see if an annotation can be used to indicate an effective .key for a column. The effective change is that the labeling of column expressions in rows has been improved to retain the original name of the ORM attribute even if used in a subquery. References: #5933 Change-Id: If251f556f7d723f50d349f765f1690d6c679d2ef
* Apply consistent labeling for all future style ORM queriesMike Bayer2021-02-111-60/+87
| | | | | | | | | | | | | | | | Fixed issue in new 1.4/2.0 style ORM queries where a statement-level label style would not be preserved in the keys used by result rows; this has been applied to all combinations of Core/ORM columns / session vs. connection etc. so that the linkage from statement to result row is the same in all cases. also repairs a cache key bug where query.from_statement() vs. select().from_statement() would not be disambiguated; the compile options were not included in the cache key for FromStatement. Fixes: #5933 Change-Id: I22f6cf0f0b3360e55299cdcb2452cead2b2458ea
* Implement support for functions as FROM with columns clause supportMike Bayer2021-02-031-1/+177
| | | | | | | | | | | | | | | | Implemented support for "table valued functions" along with additional syntaxes supported by PostgreSQL, one of the most commonly requested features. Table valued functions are SQL functions that return lists of values or rows, and are prevalent in PostgreSQL in the area of JSON functions, where the "table value" is commonly referred towards as the "record" datatype. Table valued functions are also supported by Oracle and SQL Server. Moved from I5b093b72533ef695293e737eb75850b9713e5e03 due to accidental push Fixes: #3566 Change-Id: Iea36d04c80a5ed3509dcdd9ebf0701687143fef5
* Merge "Fix many spell glitches in docstrings and comments"mike bayer2021-01-261-6/+6
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| * Fix many spell glitches in docstrings and commentsLele Gaifax2021-01-241-7/+7
| | | | | | | | | | | | | | | | | | | | These were revealed by running `pylint --disable all --enable spelling --spelling-dict en_US` over all sources. Closes: #5868 Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/5868 Pull-request-sha: bb249195d92e3b806e81ecf1192d5a1b3cd5db48 Change-Id: I96080ec93a9fbd20ce21e9e16265b3c77f22bb14
* | Replace with_labels() and apply_labels() in ORM/CoreGord Thompson2021-01-261-32/+176
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace :meth:`_orm.Query.with_labels` and :meth:`_sql.GenerativeSelect.apply_labels` with explicit getters and setters ``get_label_style`` and ``set_label_style`` to accommodate the three supported label styles: ``LABEL_STYLE_DISAMBIGUATE_ONLY`` (default), ``LABEL_STYLE_TABLENAME_PLUS_COL``, and ``LABEL_STYLE_NONE``. In addition, for Core and "future style" ORM queries, ``LABEL_STYLE_DISAMBIGUATE_ONLY`` is now the default label style. This style differs from the existing "no labels" style in that labeling is applied in the case of column name conflicts; with ``LABEL_STYLE_NONE``, a duplicate column name is not accessible via name in any case. For legacy ORM queries using :class:`_query.Query`, the table-plus-column names labeling style applied by ``LABEL_STYLE_TABLENAME_PLUS_COL`` continues to be used so that existing test suites and logging facilities see no change in behavior by default, however this style of labeling is no longer required for SQLAlchemy queries to function, as result sets are commonly matched to columns using a positional approach since SQLAlchemy 1.0. Within test suites, all use of apply_labels() / use_labels now uses the new methods. New tests added to test/sql/test_deprecations.py nad test/orm/test_deprecations.py to cover just the old apply_labels() method call. Tests in ORM that made explicit use apply_labels()/ etc. where it isn't needed for the ORM to work correctly use default label style now. Co-authored-by: Mike Bayer <mike_mp@zzzcomputing.com> Fixes: #4757 Change-Id: I5fdcd2ed4ae8c7fe62f8be2b6d0e8f66409b6a54
* Revert "Implement support for functions as FROM with columns clause support"Mike Bayer2021-01-211-67/+0
| | | | | | | This reverts commit 05a31f2708590161d4b3b4c7ff65196c99b4a22b. Atom has this little button called "push" and just pushes to master, I wasn't even *on* master. oops
* Implement support for functions as FROM with columns clause supportMike Bayer2021-01-201-0/+67
| | | | | | | WIP Fixes: #3566 Change-Id: I5b093b72533ef695293e737eb75850b9713e5e03
* chain joins from SelectState context, not SelectMike Bayer2021-01-201-1/+14
| | | | | | | | | | | | | Fixed issue in new :meth:`_sql.Select.join` method where chaining from the current JOIN wasn't looking at the right state, causing an expression like "FROM a JOIN b <onclause>, b JOIN c <onclause>" rather than "FROM a JOIN b <onclause> JOIN c <onclause>". Added :meth:`_sql.Select.outerjoin_from` method to complement :meth:`_sql.Select.join_from`. Fixes: #5858 Change-Id: I1346ebe0963bbd1e4bf868650e3ee1d6d3072f04
* Document Table/Column accessorsMike Bayer2021-01-191-1/+9
| | | | | | | | | | | | | As Sphinx will not allow us to add attributes to the .rst file while maintaining order, these have to be added as class-level attributes. Inlcude notes that "index" and "unique" parameters, while indicated by Column.index / Column.unique, do not actually indicate if the column is part of an index. Fixes: #5851 Change-Id: I18fbaf6c504c4b1005b4c51057f80397fb48b387
* happy new yearMike Bayer2021-01-041-1/+1
| | | | Change-Id: Ic5bb19ca8be3cb47c95a0d3315d84cb484bac47c
* Improve type detection for Values / TupleMike Bayer2020-12-181-0/+4
| | | | | | | | | | | | | | | | | Fixed issue in new :class:`_sql.Values` construct where passing tuples of objects would fall back to per-value type detection rather than making use of the :class:`_schema.Column` objects passed directly to :class:`_sql.Values` that tells SQLAlchemy what the expected type is. This would lead to issues for objects such as enumerations and numpy strings that are not actually necessary since the expected type is given. note this changes NullType() to raise CompileError for literal_processor; NullType() does not imply the actual value NULL as much as it does "unknown type" so this should make failure modes more clear. Fixes: #5785 Change-Id: Ifbf5e78373102380b301098f30e15011efa98b5e
* Don't emit warnings on descriptor accessMike Bayer2020-11-201-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit is revising 5162f2bc5fc0ac239f26a76fc9f0c2, which when I did it felt a little rushed but I couldn't find anything wrong. Well here we are :). Fixed issue where a :class:`.RemovedIn20Warning` would erroneously emit when the ``.bind`` attribute were accessed internally on objects, particularly when stringifying a SQL construct. Alter the deprecated() decorator so that we can use it just to add docstring warnings but not actually warn when the function is accessed, adding new argument enable_warnings that can be set to False. Added a safety feature to deprecated_20() that will disallow an ":attr:" from proceeding if enable_warnings=False isn't present, unless there's an extra flag warn_on_attribute_access, since we want Session.transaction to emit a deprecation warning. This is a little hacky but it's essentially modifying the decorator to require a positive assertion that a deprecation decorator on a descriptor should actually warn on access. Remove the warning filter for session.transaction and get tests to pass to ensure this is not also being called internally. Added tests to ensure that common places .bind can be passed as a parameter definitely warn as I was not able to find this otherwise. Fixes: #5717 Change-Id: Ia586b4f9ee6b212f3a71104b1caf40b5edd399e2
* Some small improvements on the tutorial 2.0 documentsFederico Caselli2020-11-131-1/+1
| | | | Change-Id: I7fb37d45c29307b2213bebd0ef280d73804ac473
* Merge "tutorial 2.0 WIP"mike bayer2020-10-311-26/+225
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| * tutorial 2.0 WIPreview/mike_bayer/tutorial20Mike Bayer2020-10-311-26/+225
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* | Deprecate bind args, execute() methods that were missedMike Bayer2020-10-301-0/+7
|/ | | | | | in particular text(bind), DDL.execute(). Change-Id: Ie85ae9f61219182f5649f68e5f52b4923843199c
* Ensure escaping of percent signs in columns, parametersMike Bayer2020-10-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | Improved support for column names that contain percent signs in the string, including repaired issues involving anoymous labels that also embedded a column name with a percent sign in it, as well as re-established support for bound parameter names with percent signs embedded on the psycopg2 dialect, using a late-escaping process similar to that used by the cx_Oracle dialect. * Added new constructor for _anonymous_label() that ensures incoming string tokens based on column or table names will have percent signs escaped; abstracts away the format of the label. * generalized cx_Oracle's quoted_bind_names facility into the compiler itself, and leveraged this for the psycopg2 dialect's issue with percent signs in names as well. the parameter substitution is now integrated with compiler.construct_parameters() as well as the recently reworked set_input_sizes(), reducing verbosity in the cx_Oracle dialect. Fixes: #5653 Change-Id: Ia2ad13ea68b4b0558d410026e5a33f5cb3fbab2c
* Add deprecation for base Executable.bindMike Bayer2020-10-161-0/+23
| | | | | | | | | | These attributes will be removed in SQLAlchemy 2.0. Also alters the deprecation message to qualify the type of object correctly. this in turn requires changes in the warnings filter and deprecation tests. Change-Id: I5779d9813e88f42e5db0c7b5e3ffff1d1535c203
* Deprecate duplicated column names in Table definitionMike Bayer2020-10-121-1/+1
| | | | | | | | | | | | | | 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
* Address minor comments from previous changesFederico Caselli2020-10-061-1/+1
| | | | | | | Change how pypy is detected. From I0952e54ed9af2952ea340be1945311376ffc1ad2 Fix typos. From Ibb5871a457c0555f82b37e354e7787d15575f1f7 Change-Id: I9657e602267590f10a74df27a84e4292da94c30a
* Fetch first supportFederico Caselli2020-10-021-17/+97
| | | | | | | | | Add support to ``FETCH {FIRST | NEXT} [ count ] {ROW | ROWS} {ONLY | WITH TIES}`` in the select for the supported backends, currently PostgreSQL, Oracle and MSSQL. Fixes: #5576 Change-Id: Ibb5871a457c0555f82b37e354e7787d15575f1f7
* raise on lower-case column shared to multiple tablesMike Bayer2020-09-301-0/+7
| | | | | | | | | | 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
* Add deprecation warning for .join().alias()Gord Thompson2020-09-281-40/+48
| | | | | | | | | The :meth:`_sql.Join.alias` method is deprecated and will be removed in SQLAlchemy 2.0. An explicit select + subquery, or aliasing of the inner tables, should be used instead. Fixes: #5010 Change-Id: Ic913afc31f0d70b0605f9a7af2742a0de1f9ad19
* new docs WIPMike Bayer2020-09-241-9/+72
| | | | | | | | | | | | | | | 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
* Complete deprecation of from_self()Mike Bayer2020-09-181-0/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For most from_self() tests, move them into test/orm/test_deprecated.py and replace the existing test with one that uses aliased() plus a subquery. This then revealed a few more issues. Related items: * Added slice() method to GenerativeSelect, to match that of orm.Query and to make possible migration of one of the from_self() tests. moved the utility functions used for this from orm/util into sql/util. * repairs a caching issue related to subqueryload where information being derived from the cached path info was mixing up with query information based on the per-query state, specifically an AliasedClass that is per query. * for the above issue, it seemed like path_registry maybe had to change so that it represents AliasedClass objects as their cache key rather than on identity, but it wasn't needed. still seems like it would be more correct. * enhances the error message raised by coercions for a case such as when an AliasedClass holds onto a select() object and not a subquery(); will name the original and resolved object for clarity (although how is AliasedClass able to accept a Select() object in the first place?) * Added _set_propagate_attrs() to Query so that again if it's passed to AliasedClass, it doesn't raise an error during coercion, but again maybe that should also be rejected up front Fixes: #5368 Change-Id: I5912aa611d899acc87a75eb5ee9f95990592f210
* Create a framework to allow all SQLALCHEMY_WARN_20 to passMike Bayer2020-09-161-1/+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
* Repair documentation issuesMike Bayer2020-09-091-3/+5
| | | | | | | Fixes some remaining issues detailed at #5428. Fixes: #5428 Change-Id: I942a64411766fc82f30791eee570747a218af77d
* Update select usage to use the new 1.4 formatFederico Caselli2020-09-081-41/+40
| | | | | | | | | | | | | | | | 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
* Robustness for lambdas, lambda statementsMike Bayer2020-08-051-11/+21
| | | | | | | | | | | | | | | | | | | | in order to accommodate relationship loaders with lambda caching, a lot more is needed. This is a full refactor of the lambda system such that it now has two levels of caching; the first level caches what can be known from the __code__ element, then the next level of caching is against the lambda itself and the contents of __closure__. This allows for the elements inside the lambdas, like columns and entities, to change and then be part of the cache key. Lazy/selectinloads' use of baked queries had to add distinct cache key elements, which was attempted here but overall things needed to be more robust than that. This commit is broken out from the very long and sprawling commit at Id6b5c03b1ce9ddb7b280f66792212a0ef0a1c541 . Change-Id: I29a513c98917b1d503abfdd61e6b6e8800851aa8
* Convert remaining ORM APIs to support 2.0 styleMike Bayer2020-07-111-70/+96
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 Bayer2020-07-081-110/+407
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 Bayer2020-07-031-1/+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
* Provide example for existsFederico Caselli2020-06-271-1/+9
| | | | | | Fixes: #5423 Change-Id: I716f8de17c49d7eefbbce5ddd9da203bfc9fe47f
* Fix a wide variety of typos and broken linksaplatkouski2020-06-251-142/+154
| | | | | | | | | | | | 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
* Turn on caching everywhere, add loggingMike Bayer2020-06-101-11/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 Bayer2020-06-061-3/+3
| | | | | | | | | | | | | | | 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 Bayer2020-05-311-14/+18
| | | | | | | | | | | | | | | | | | | | 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 Bayer2020-05-281-3/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 Bayer2020-05-251-22/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 Bayer2020-05-241-112/+341
| | | | | | | | | | | | | | | | | | | | | | | | | | 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
* fix typo in reference documentationFederico Caselli2020-05-231-1/+1
| | | | Change-Id: I5720635863f0d8a8ebfa4ddc51008bb93c1067b4
* Performance fixes for new result setMike Bayer2020-05-211-13/+16
| | | | | | | | | | | 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
* fix table.schema version to 1.3.18Mike Bayer2020-05-191-1/+1
| | | | | Fixes: #5338 Change-Id: I12ce8021f5627c306c768b74da991ef4af0a5b55
* Streamline visitors.iterateMike Bayer2020-05-181-5/+6
| | | | | | | | | | | | | | | | | | | | 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
* Add 'schema' parameter to tableDylan Modesitt2020-05-101-3/+14
| | | | | | | | | | | | Added a "schema" parameter to the :func:`_expression.table` construct, allowing ad-hoc table expressions to also include a schema name. Pull request courtesy Dylan Modesitt. Fixes: #5309 Closes: #5310 Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/5310 Pull-request-sha: ce85681050500186678131f948b6ea277a65dc17 Change-Id: I32015d593e1ee1121c7426fbffdcc565d025fad1
* 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 Bayer2020-04-141-442/+636
| | | | | | | | Replaces a wide array of Sphinx-relative doc references with an abbreviated absolute form now supported by zzzeeksphinx. Change-Id: I94bffcc3f37885ffdde6238767224296339698a2
* Enable zzzeeksphinx module prefixesMike Bayer2020-04-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | zzzeeksphinx 1.1.2 in git can now convert short prefix names in a configured lookup to fully qualified module names, so that we can have succinct and portable pyrefs that still resolve absolutely. It also includes a formatter that will format all pyrefs in a fully consistent way regardless of the package path, by unconditionally removing all package tokens but always leaving class names in place including for methods, which means we no longer have to deal with tildes in pyrefs. The most immediate goal of the absolute prefixes is that we have lots of "ambiguous" names that appear in muliple places, like select(), ARRAY, ENUM etc. With the incoming future packages there is going to be lots of name overlap so it is necessary that all names eventually use absolute package paths when Sphinx receives them. In multiple stages, pyrefs will be converted using the zzzeeksphinx tools/fix_xrefs.py tool so that doclinks can be made absolute using symbolic prefixes. For this review, the actual search and replace of symbols is not performed, instead some general cleanup to prepare the docs as well as a lookup file used by the tool to do the conversion. this relatively small patch will be backported with appropriate changes to 1.3, 1.2, 1.1 and the tool can then be run on each branch individually. We are shooting for almost no warnings at all for master (still a handful I can't figure out which don't seem to have any impact) , very few for 1.3, and for 1.2 / 1.1 we hope for a significant reduction in warnings. Overall for all versions pyrefs should always point to the correct target, if they are in fact hyperlinked. it's better for a ref to go nowhere and be plain text than go to the wrong thing. Right now, hundreds of API links are pointing to the wrong thing as they are ambiguous names such as refresh(), insert(), update(), select(), join(), JSON etc. and Sphinx sends these all to essesntially random destinations among as many as five or six possible choices per symbol. A shorthand system that allows us to use absolute refs without having to type out a full blown absoulte module is the only way this is going to work, and we should ultimately seek to abandon any use of prefix dot for lookups. Everything should be on an underscore token so at the very least the module spaces can be reorganized without having to search and replace the entire documentation every time. Change-Id: I484a7329034af275fcdb322b62b6255dfeea9151