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* 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
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| * 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
* Update transaction / connection handlingMike Bayer2020-05-171-261/+446
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | step one, do away with __connection attribute and using awkward AttributeError logic step two, move all management of "connection._transaction" into the transaction objects themselves where it's easier to follow. build MarkerTransaction that takes the role of "do-nothing block" new connection datamodel is: connection._transaction, always a root, connection._nested_transaction, always a nested. nested transactions still chain to each other as this is still sort of necessary but they consider the root transaction separately, and the marker transactions not at all. introduce new InvalidRequestError subclass PendingRollbackError. Apply to connection and session for all cases where a transaction needs to be rolled back before continuing. Within Connection, both PendingRollbackError as well as ResourceClosedError are now raised directly without being handled by handle_dbapi_error(); this removes these two exception cases from the handle_error event handler as well as from StatementError wrapping, as these two exceptions are not statement oriented and are instead programmatic issues, that the application is failing to handle database errors properly. Revise savepoints so that when a release fails, they set themselves as inactive so that their rollback() method does not throw another exception. Give savepoints another go on MySQL, can't get release working however get support for basic round trip going Fixes: #5327 Change-Id: Ia3cbbf56d4882fcc7980f90519412f1711fae74d
* Actively unset reset agent in discard transactionMike Bayer2020-05-141-15/+3
| | | | | | | | | | | | | | | The assumptions in _discard_transaction from 916e1fea25afcd07fa1d1d2f72043b372cd02223 were too narrow, assuming that if the given transaction were not our "current" one, that this would not be the reset agent. however as the legacy behvaior is that even a "nested" transaction gets set as "self._transaction", this did not accommodate for the nested transaction being thrown away. We will attempt to refine all of this logic in #5327 for 1.4 /master assuming this is feasible for the full suite of current use cases. Fixes: #5326 Change-Id: I6787e82c9e50c23317f87d0d094122c6a6f066da
* Assert reset agent always set correctly and is activeMike Bayer2020-05-131-3/+21
| | | | | | | | | | | | | | | | | | | | Fixed fairly critical issue where the DBAPI connection could be returned to the connection pool while still in an un-rolled-back state. The reset agent responsible for rolling back the connection could be corrupted in the case that the transaction was "closed" without being rolled back or committed, which can occur in some scenarios when using ORM sessions and emitting .close() in a certain pattern involving savepoints. The fix ensures that the reset agent is always active. note that the reset agent will go away in 2.0 and the only real purpose of it is for logging of ROLLBACK. Apparently with the SQLite singleton engine in the test suite, there are some strucutral mismatches in the test fixtures where the reset agent is getting set differently than the transaction likely due to the same connection being shared in multiple context, though it's unclear. Fixes: #5326 Change-Id: If056870ea70a2d9a1749768988d5e023f3061b31
* Documentation updates for ResultProxy -> ResultMike Bayer2020-05-011-10/+10
| | | | | | | | | This is based off of I8091919d45421e3f53029b8660427f844fee0228 and includes all documentation-only changes as a separate merge, once the parent is merged. Change-Id: I711adea23df0f9f0b1fe7c76210bd2de6d31842d
* Create initial 2.0 engine implementationMike Bayer2020-04-161-90/+226
| | | | | | | | | | | | | | | | | | | Implemented the SQLAlchemy 2 :func:`.future.create_engine` function which is used for forwards compatibility with SQLAlchemy 2. This engine features always-transactional behavior with autobegin. Allow execution options per statement execution. This includes that the before_execute() and after_execute() events now accept an additional dictionary with these options, empty if not passed; a legacy event decorator is added for backwards compatibility which now also emits a deprecation warning. Add some basic tests for execution, transactions, and the new result object. Build out on a new testing fixture that swaps in the future engine completely to start with. Change-Id: I70e7338bb3f0ce22d2f702537d94bb249bd9fb0a Fixes: #4644
* Set up absolute references for create_engine and relatedMike Bayer2020-04-141-15/+18
| | | | | | | includes more replacements for create_engine(), Connection, disambiguation of Result from future/baked Change-Id: Icb60a79ee7a6c45ea9056c211ffd1be110da3b5e
* Run search and replace of symbolic module namesMike Bayer2020-04-141-173/+220
| | | | | | | | 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 Caselli2020-04-091-13/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - 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
* Try to measure new style caching in the ORM, take twoMike Bayer2020-04-011-4/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Supercedes: If78fbb557c6f2cae637799c3fec2cbc5ac248aaf Trying to see if by making the cache key memoized, we still can have the older "identity" form of caching which is the cheapest of all, at the same time as the newer "cache key each time" version that is not nearly as cheap; but still much cheaper than no caching at all. Also needed is a per-execution update of _keymap when we invoke from a cached select, so that Column objects that are anonymous or otherwise adapted will match up. this is analogous to the adaption of bound parameters from the cache key. Adds test coverage for the keymap / construct_params() changes related to caching. Also hones performance to a large extent for statement construction and cache key generation. Also includes a new memoized attribute approach that vastly simplifies the previous approach of "group_expirable_memoized_property" and finally integrates cleanly with _clone(), _generate(), etc. no more hardcoding of attributes is needed, as well as that most _reset_memoization() calls are no longer needed as the reset is inherent in a _generate() call; this also has dramatic performance improvements. Change-Id: I95c560ffcbfa30b26644999412fb6a385125f663
* Convert schema_translate to a post compileMike Bayer2020-03-241-43/+25
| | | | | | | | | | | | | | | | Revised the :paramref:`.Connection.execution_options.schema_translate_map` feature such that the processing of the SQL statement to receive a specific schema name occurs within the execution phase of the statement, rather than at the compile phase. This is to support the statement being efficiently cached. Previously, the current schema being rendered into the statement for a particular run would be considered as part of the cache key itself, meaning that for a run against hundreds of schemas, there would be hundreds of cache keys, rendering the cache much less performant. The new behavior is that the rendering is done in a similar manner as the "post compile" rendering added in 1.4 as part of :ticket:`4645`, :ticket:`4808`. Fixes: #5004 Change-Id: Ia5c89eb27cc8dc2c5b8e76d6c07c46290a7901b6
* Deprecate plain string in execute and introduce `exec_driver_sql`Federico Caselli2020-03-211-19/+92
| | | | | | | | | | | | | | | Execution of literal sql string is deprecated in the :meth:`.Connection.execute` and a warning is raised when used stating that it will be coerced to :func:`.text` in a future release. To execute a raw sql string the new connection method :meth:`.Connection.exec_driver_sql` was added, that will retain the previous behavior, passing the string to the DBAPI driver unchanged. Usage of scalar or tuple positional parameters in :meth:`.Connection.execute` is also deprecated. Fixes: #4848 Fixes: #5178 Change-Id: I2830181054327996d594f7f0d59c157d477c3aa9
* Rework select(), CompoundSelect() in terms of CompileStateMike Bayer2020-03-101-9/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Continuation of I408e0b8be91fddd77cf279da97f55020871f75a9 - add an options() method to the base Generative construct. this will be where ORM options can go - Change Null, False_, True_ to be singletons, so that we aren't instantiating them and having to use isinstance. The previous issue with this was that they would produce dupe labels in SELECT statements. Apply the duplicate column logic, newly added in 1.4, to these objects as well as to non-apply-labels SELECT statements in general as a means of improving this. - create a revised system for generating ClauseList compilation constructs that simplfies up front creation to not actually use ClauseList; a simple tuple is rendered by the compiler using the same constrcution rules as what are used for ClauseList but without creating the actual object. Apply to Select, CompoundSelect, revise Update, Delete - Select, CompoundSelect get an initial CompileState implementation. All methods used only within compilation are moved here - refine update/insert/delete compile state to not require an outside boolean - refine and simplify Select._copy_internals - rework bind(), which is going away, to not use some of the internal traversal stuff - remove "autocommit", "for_update" parameters from Select, references #4643 - remove "autocommit" parameter from TextClause , references #4643 - add deprecation warnings for statement.execute(), engine.execute(), statement.scalar(), engine.scalar(). Fixes: #5193 Change-Id: I04ca0152b046fd42c5054ba10f37e43fc6e5a57b
* Run handle_error for any exceptions raised in execute_context()Mike Bayer2020-03-031-30/+31
| | | | | | | | | | | | | | | | | | | | | Observing a SQLite connection/cursor being hung on test_resultset -> PositionalTextTest -> test_dupe_col_obj. this uses connectionless execution and the result object fails to be constructed. When that happens, there is no path for the cursor or connection to be closed / released. Recent changes with the exception assertions in #4849 seem to be causing a cycle to last a little longer than usual which is exposing this issue for one particular test on SQLite. As we want to get rid of weakref cleanup, evaluate why we dont have handle_dbapi_exception for this whole block, as after_cursor_execute can raise, result construction can raise, autocommit can raise, close can raise, there does not seem to be a reason these things should be outside of the block that gets cleaned up. Fixes: #5182 Change-Id: I640ac55e8c5f39d287f779fbb5dc0ab727218ca3
* Ensure all nested exception throws have a causeMike Bayer2020-03-021-11/+20
| | | | | | | | | | | | | | | 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/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Deprecate connection branchingMike Bayer2020-02-211-1/+16
| | | | | | | | | | | | | | | The :meth:`.Connection.connect` method is deprecated as is the concept of "connection branching", which copies a :class:`.Connection` into a new one that has a no-op ".close()" method. This pattern is oriented around the "connectionless execution" concept which is also being removed in 2.0. As part of this change we begin to move the internals away from "connectionless execution" overall. Remove the "connectionless execution" concept from the reflection internals and replace with explicit patterns at the Inspector level. Fixes: #5131 Change-Id: Id23d28a9889212ac5ae7329b85136157815d3e6f
* Query linter optionAlessio Bogon2020-01-221-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Added "from linting" as a built-in feature to the SQL compiler. This allows the compiler to maintain graph of all the FROM clauses in a particular SELECT statement, linked by criteria in either the WHERE or in JOIN clauses that link these FROM clauses together. If any two FROM clauses have no path between them, a warning is emitted that the query may be producing a cartesian product. As the Core expression language as well as the ORM are built on an "implicit FROMs" model where a particular FROM clause is automatically added if any part of the query refers to it, it is easy for this to happen inadvertently and it is hoped that the new feature helps with this issue. The original recipe is from: https://github.com/sqlalchemy/sqlalchemy/wiki/FromLinter The linter is now enabled for all tests in the test suite as well. This has necessitated that a lot of the queries be adjusted to not include cartesian products. Part of the rationale for the linter to not be enabled for statement compilation only was to reduce the need for adjustment for the many test case statements throughout the test suite that are not real-world statements. This gerrit is adapted from Ib5946e57c9dba6da428c4d1dee6760b3e978dda0. Fixes: #4737 Change-Id: Ic91fd9774379f895d021c3ad564db6062299211c Closes: #4830 Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/4830 Pull-request-sha: f8a21aa6262d1bcc9ff0d11a2616e41fba97a47a
* happy new yearMike Bayer2020-01-011-1/+1
| | | | Change-Id: I08440dc25e40ea1ccea1778f6ee9e28a00808235
* Clarify isolation_level documentationMike Bayer2019-10-151-20/+14
| | | | | Fixes: #4909 Change-Id: I32114a8349c1d2d0a837610ccc74f9e789ed20f5
* pass executemany context to _repr_paramsMike Bayer2019-10-111-1/+10
| | | | | | | | | | | | | | | | | | Fixed bug where parameter repr as used in logging and error reporting needs additional context in order to distinguish between a list of parameters for a single statement and a list of parameter lists, as the "list of lists" structure could also indicate a single parameter list where the first parameter itself is a list, such as for an array parameter. The engine/connection now passes in an additional boolean indicating how the parameters should be considered. The only SQLAlchemy backend that expects arrays as parameters is that of psycopg2 which uses pyformat parameters, so this issue has not been too apparent, however as other drivers that use positional gain more features it is important that this be supported. It also eliminates the need for the parameter repr function to guess based on the parameter structure passed. Fixes: #4902 Change-Id: I086246ee0eb51484adbefd83e07295fa56576c5f
* Remove deprecated extension and similar classesMike Bayer2019-10-061-4/+0
| | | | | | | | | | All long-deprecated "extension" classes have been removed, including MapperExtension, SessionExtension, PoolListener, ConnectionProxy, AttributExtension. These classes have been deprecated since version 0.7 long superseded by the event listener system. Fixes: #4638 Change-Id: If4156d4956b10847bd93b6408a7c52ff5168db9b
* Add hide_parameters flag to create_engineMike Bayer2019-08-221-3/+14
| | | | | | | | | Added new parameter :paramref:`.create_engine.hide_parameters` which when set to True will cause SQL parameters to no longer be logged, nor rendered in the string representation of a :class:`.StatementError` object. Fixes: #4815 Change-Id: Ib87f868b6936cf6b42b192644e9d732ec24266c2
* Modernize internal reflectionMike Bayer2019-08-061-16/+58
| | | | | | | | | | | | | | | | | | | | | | | - Deprecated remaining engine-level introspection and utility methods including :meth:`.Engine.run_callable`, :meth:`.Engine.transaction`, :meth:`.Engine.table_names`, :meth:`.Engine.has_table`. The utility methods are superseded by modern context-manager patterns, and the table introspection tasks are suited by the :class:`.Inspector` object. - The internal dialect method ``Dialect.reflecttable`` has been removed. A review of third party dialects has not found any making use of this method, as it was already documented as one that should not be used by external dialects. Additionally, the private ``Engine._run_visitor`` method is also removed. - The long-deprecated ``Inspector.get_table_names.order_by`` parameter has been removed. - The :paramref:`.Table.autoload_with` parameter now accepts an :class:`.Inspector` object directly, as well as any :class:`.Engine` or :class:`.Connection` as was the case before. Fixes: #4755 Change-Id: Iec3a8b0f3e298ba87d532b16fac1e1132f464e21
* Remove threadlocal engine strategy, engine strategies pool threadlocalMike Bayer2019-07-151-63/+17
| | | | | | | | | | | | The "threadlocal" execution strategy, deprecated in 1.3, has been removed for 1.4, as well as the concept of "engine strategies" and the ``Engine.contextual_connect`` method. The "strategy='mock'" keyword argument is still accepted for now with a deprecation warning; use :func:`.create_mock_engine` instead for this use case. Fixes: #4632 Change-Id: I8a351f9fa1f7dfa2a56eec1cd2d1a4b9d65765a2 (cherry picked from commit b368c49b44c5716d93c7428ab22b6761c6ca7cf5)
* Ensure .engine is part of Connectable interface, implement as descriptorMike Bayer2019-07-081-1/+4
| | | | | | | | | | Fixed bug where using reflection function such as :meth:`.MetaData.reflect` with an :class:`.Engine` object that had execution options applied to it would fail, as the resulting :class:`.OptionEngine` proxy object failed to include a ``.engine`` attribute used within the reflection routines. Fixes: #4754 Change-Id: I6c342af5c6db6fe362b9d25f3f26d6859f62f87a
* Don't discard inactive transaction until it is explicitly rolled backMike Bayer2019-06-101-15/+52
| | | | | | | | | | | | | | | | | The :class:`.Connection` object will now not clear a rolled-back transaction until the outermost transaction is explicitly rolled back. This is essentially the same behavior that the ORM :class:`.Session` has had for a long time, where an explicit call to ``.rollback()`` on all enclosing transactions is required for the transaction to logically clear, even though the DBAPI-level transaction has already been rolled back. The new behavior helps with situations such as the "ORM rollback test suite" pattern where the test suite rolls the transaction back within the ORM scope, but the test harness which seeks to control the scope of the transaction externally does not expect a new transaction to start implicitly. Fixes: #4712 Change-Id: Ibc6c8d981cff31594a5d26dd5203fd9cfcea1c74
* Add getters for all execution_optionsDaniel Lister2019-01-251-0/+34
| | | | | | | | | | | | | | | Added accessors for execution options to Core and ORM, via :meth:`.Query.get_execution_options`, :meth:`.Connection.get_execution_options`, :meth:`.Engine.get_execution_options`, and :meth:`.Executable.get_execution_options`. PR courtesy Daniel Lister. Fixes: #4406 Closes: #4465 Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/4465 Pull-request-sha: 9674688bb5e80471a6a421bac06f995c2e64f8f7 Change-Id: I93ba51d7a2d687e255edd6938db15615e56dd237
* Add deprecation warnings to all deprecated APIsMike Bayer2019-01-231-21/+21
| | | | | | | | | | | | | | | A large change throughout the library has ensured that all objects, parameters, and behaviors which have been noted as deprecated or legacy now emit ``DeprecationWarning`` warnings when invoked. As the Python 3 interpreter now defaults to displaying deprecation warnings, as well as that modern test suites based on tools like tox and pytest tend to display deprecation warnings, this change should make it easier to note what API features are obsolete. See the notes added to the changelog and migration notes for further details. Fixes: #4393 Change-Id: If0ea11a1fc24f9a8029352eeadfc49a7a54c0a1b
* - pep8 fixMike Bayer2019-01-161-1/+2
| | | | Change-Id: I5e2e013c3460c035ad80dae7fd08efe5d1676a5d
* Convert most "See also" phrases into .. seealso::Mike Bayer2019-01-151-16/+28
| | | | | Change-Id: Ie32598b895c1c5f5bce7c8e1573abbcfe9d434a8 (cherry picked from commit e81d3815abb36c52b0019dee6e4f67990e3d1c7d)
* Remove version directives for 0.6, 0.7, 0.8Mike Bayer2019-01-151-11/+5
| | | | | | | | | - fix a few "seealso"s - ComparableProprerty's "superseded in 0.7" becomes deprecated in 0.7 Backport to currently maintained doc versions 1.2, 1.1 Change-Id: Ib1fcb2df8673dbe5c4ffc47f3896a60d1dfcb4b2
* happy new yearMike Bayer2019-01-111-1/+1
| | | | Change-Id: I6a71f4924d046cf306961c58dffccf21e9c03911
* Post black reformattingMike Bayer2019-01-061-22/+27
| | | | | | | | | | | | | Applied on top of a pure run of black -l 79 in I7eda77fed3d8e73df84b3651fd6cfcfe858d4dc9, this set of changes resolves all remaining flake8 conditions for those codes we have enabled in setup.cfg. Included are resolutions for all remaining flake8 issues including shadowed builtins, long lines, import order, unused imports, duplicate imports, and docstring issues. Change-Id: I4f72d3ba1380dd601610ff80b8fb06a2aff8b0fe
* Run black -l 79 against all source filesMike Bayer2019-01-061-192/+253
| | | | | | | | | | | | | | This is a straight reformat run using black as is, with no edits applied at all. The black run will format code consistently, however in some cases that are prevalent in SQLAlchemy code it produces too-long lines. The too-long lines will be resolved in the following commit that will resolve all remaining flake8 issues including shadowed builtins, long lines, import order, unused imports, duplicate imports, and docstring issues. Change-Id: I7eda77fed3d8e73df84b3651fd6cfcfe858d4dc9
* Fix reference leak in compiled cacheOlivier Grisel2018-04-251-3/+3
| | | | | | | | | | Fixed a reference leak issue where the values of the parameter dictionary used in a statement execution would remain referenced by the "compiled cache", as a result of storing the key view used by Python 3 dictionary keys(). Pull request courtesy Olivier Grisel. Change-Id: Icfb0f38111a165780f6dd3e4e3382a03df79ce26 Pull-request: https://github.com/zzzeek/sqlalchemy/pull/441
* Add flag for class-level disallow of events, apply to OptionEngineMike Bayer2018-02-071-0/+16
| | | | | | | | | | | | | | | | | | | | Fixed bug where events associated with an :class:`Engine` at the class level would be doubled when the :meth:`.Engine.execution_options` method were used. To achieve this, the semi-private class :class:`.OptionEngine` no longer accepts events directly at the class level and will raise an error; the class only propagates class-level events from its parent :class:`.Engine`. Instance-level events continue to work as before. The comments present another way of doing this where we would copy events from the parent engine at option time rather than linking the event listeners, but this would be a behavioral change that adding new events to the parent engine would not take effect for an already-created OptionEngine. Change-Id: Id128516f54103fbad9a2210d6571eceb59c8b0cb Fixes: #4181