summaryrefslogtreecommitdiff
path: root/lib/sqlalchemy/engine/default.py
Commit message (Collapse)AuthorAgeFilesLines
* Ensure escaping of percent signs in columns, parametersMike Bayer2020-10-171-3/+28
| | | | | | | | | | | | | | | | | | | | | | | | 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
* Genericize setinputsizes and support pyodbcMike Bayer2020-10-161-80/+52
| | | | | | | | | | | | Reworked the "setinputsizes()" set of dialect hooks to be correctly extensible for any arbirary DBAPI, by allowing dialects individual hooks that may invoke cursor.setinputsizes() in the appropriate style for that DBAPI. In particular this is intended to support pyodbc's style of usage which is fundamentally different from that of cx_Oracle. Added support for pyodbc. Fixes: #5649 Change-Id: I9f1794f8368bf3663a286932cfe3992dae244a10
* Deprecate engine-wise ss cursors; repair mariadbconnectorMike Bayer2020-09-131-1/+24
| | | | | | | | | | | | | | | | | | | The server_side_cursors engine-wide feature relies upon regexp parsing of statements a well as general guessing as to when the feature should be used. This is not within the 2.0 way of doing things and should be removed. Additionally, mariadbconnector defaults to unbuffered cursors; add new cursor hooks so that mariadbconnector can specify buffered or unbuffered cursors without too much difficulty. This will also correctly default mariadbconnector to buffered cursors which should repair the segfaults we've been getting. Try to restore the assert_raises that was removed in 5b6dfc0c38bf1f01da4b8 to see if mariadbconnector segfaults are resolved. Change-Id: I77f1c972c742e40694972f578140bb0cac8c39eb
* Merge "Do not specify type on mssql by default"mike bayer2020-09-121-3/+0
|\
| * Do not specify type on mssql by defaultFederico Caselli2020-09-121-3/+0
| | | | | | | | | | | | | | Make optional sequences render as identity in mssql Remove unused dialect option sequence_default_column_type Change-Id: I821eeffcb442f8d1b69186a9b798b15c3d8d6ff3
* | Update select usage to use the new 1.4 formatFederico Caselli2020-09-081-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* | Create connection characteristics API; implement postgresql flagsMike Bayer2020-09-081-22/+66
| | | | | | | | | | | | | | | | | | | | | | Added support for PostgreSQL "readonly" and "deferrable" flags for all of psycopg2, asyncpg and pg8000 dialects. This takes advantage of a newly generalized version of the "isolation level" API to support other kinds of session attributes set via execution options that are reliably reset when connections are returned to the connection pool. Fixes: #5549 Change-Id: I0ad6d7a095e49d331618274c40ce75c76afdc7dd
* | Updates for MariaDB sequencesFederico Caselli2020-08-221-8/+1
|/ | | | | | | | | | | | MariaDB should not run a Sequence if it has optional=True. Additionally, rework the rules in crud.py to accommodate the new combination MariaDB brings us, which is a dialect that supports both cursor.lastrowid, explicit sequences, *and* no support for returning. Co-authored-by: Mike Bayer <mike_mp@zzzcomputing.com> Fixes: #5528 Change-Id: I9a8ea69a34983affa95dfd22186e2908fdf0d58c
* Create a real type for Tuple() and handle appropriately in compilerMike Bayer2020-08-171-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | Improved the :func:`_sql.tuple_` construct such that it behaves predictably when used in a columns-clause context. The SQL tuple is not supported as a "SELECT" columns clause element on most backends; on those that do (PostgreSQL, not surprisingly), the Python DBAPI does not have a "nested type" concept so there are still challenges in fetching rows for such an object. Use of :func:`_sql.tuple_` in a :func:`_sql.select` or :class:`_orm.Query` will now raise a :class:`_exc.CompileError` at the point at which the :func:`_sql.tuple_` object is seen as presenting itself for fetching rows (i.e., if the tuple is in the columns clause of a subquery, no error is raised). For ORM use,the :class:`_orm.Bundle` object is an explicit directive that a series of columns should be returned as a sub-tuple per row and is suggested by the error message. Additionally ,the tuple will now render with parenthesis in all contexts. Previously, the parenthesization would not render in a columns context leading to non-defined behavior. As part of this change, Tuple receives a dedicated datatype which appears to allow us the very desirable change of removing the bindparam._expanding_in_types attribute as well as ClauseList._tuple_values (which might already have not been needed due to #4645). Fixes: #5127 Change-Id: Iecafa0e0aac2f1f37ec8d0e1631d562611c90200
* Implement rudimentary asyncio support w/ asyncpgMike Bayer2020-08-131-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | Using the approach introduced at https://gist.github.com/zzzeek/6287e28054d3baddc07fa21a7227904e We can now create asyncio endpoints that are then handled in "implicit IO" form within the majority of the Core internals. Then coroutines are re-exposed at the point at which we call into asyncpg methods. Patch includes: * asyncpg dialect * asyncio package * engine, result, ORM session classes * new test fixtures, tests * some work with pep-484 and a short plugin for the pyannotate package, which seems to have so-so results Change-Id: Idbcc0eff72c4cad572914acdd6f40ddb1aef1a7d Fixes: #3414
* Don't link on_connect to first_connect event handlerMike Bayer2020-08-071-0/+2
| | | | | | | | | | | | | Adjusted the dialect initialization process such that the :meth:`_engine.Dialect.on_connect` is not called a second time on the first connection. The hook is called first, then the :meth:`_engine.Dialect.initialize` is called if that connection is the first for that dialect, then no more events are called. This eliminates the two calls to the "on_connect" function which can produce very difficult debugging situations. Fixes: #5497 Change-Id: Icefc2e884e30ee7b4ac84b99dc54bf992a6085e3
* Robustness for lambdas, lambda statementsMike Bayer2020-08-051-4/+24
| | | | | | | | | | | | | | | | | | | | 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
* Revise setinputsizes approachMike Bayer2020-07-191-44/+60
| | | | | | | | | | | | | | | | | | | | | | | in order to support asyncpg as well as pg8000, we need to revise setinputsizes to work for more cases as well as adjust NativeForEmulated a bit to work more completely with the INTERVAL datatype. - put most of the setinputsizes work into the compiler where the computation can be cached. - support per-element setinputsizes for a tuple - adjust TypeDecorator so that _unwrapped_dialect_impl will honor a type that the dialect links to directly in it's adaption mapping. Decouble _unwrapped_dialect_impl from TypeDecorator._gen_dialect_impl() which has a different purpose. This allows setinputsizes to do the right thing with the INTERVAL datatype. - test cases for Oracle with Variant continue to work Change-Id: I9e1ea33aeca3b92b365daa4a356d778191070c03
* Add future=True to create_engine/Session; unify select()Mike Bayer2020-07-081-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Merge "ORM executemany returning"mike bayer2020-06-281-3/+4
|\
| * ORM executemany returningMike Bayer2020-06-271-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Build on #5401 to allow the ORM to take advanage of executemany INSERT + RETURNING. Implemented the feature updated tests to support INSERT DEFAULT VALUES, needed to come up with a new syntax for compiler INSERT INTO table (anycol) VALUES (DEFAULT) which can then be iterated out for executemany. Added graceful degrade to plain executemany for PostgreSQL <= 8.2 Renamed EXECUTEMANY_DEFAULT to EXECUTEMANY_PLAIN Fix issue where unicode identifiers or parameter names wouldn't work with execute_values() under Py2K, because we have to encode the statement and therefore have to encode the insert_single_values_expr too. Correct issue from #5401 to support executemany + return_defaults for a PK that is explicitly pre-generated, meaning we aren't actually getting RETURNING but need to return it from compiled_parameters. Fixes: #5263 Change-Id: Id68e5c158c4f9ebc33b61c06a448907921c2a657
* | Merge "Fix a wide variety of typos and broken links"mike bayer2020-06-261-2/+2
|\ \ | |/ |/|
| * Fix a wide variety of typos and broken linksaplatkouski2020-06-251-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | 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 "Default psycopg2 executemany mode to "values_only""mike bayer2020-06-261-54/+29
|\ \ | |/ |/|
| * Default psycopg2 executemany mode to "values_only"Mike Bayer2020-06-251-54/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* | Use time.perf_counter() for cache time measurementMike Bayer2020-06-241-2/+1
|/ | | | | | See https://twitter.com/raymondh/status/1275937373080023040 Change-Id: Iaa0abb0c433ccedfbd88d00e3970120242ba379b
* Propose using RETURNING for bulk updates, deletesMike Bayer2020-06-231-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch makes several improvements in the area of bulk updates and deletes as well as the new session mechanics. RETURNING is now used for an UPDATE or DELETE statement emitted for a diaelct that supports "full returning" in order to satisfy the "fetch" strategy; this currently includes PostgreSQL and SQL Server. The Oracle dialect does not support RETURNING for more than one row, so a new dialect capability "full_returning" is added in addition to the existing "implicit_returning", indicating this dialect supports RETURNING for zero or more rows, not just a single identity row. The "fetch" strategy will gracefully degrade to the previous SELECT mechanics for dialects that do not support RETURNING. Additionally, the "fetch" strategy will attempt to use evaluation for the VALUES that were UPDATEd, rather than just expiring the updated attributes. Values should be evalutable in all cases where the value is not a SQL expression. The new approach also incurs some changes in the session.execute mechanics, where do_orm_execute() event handlers can now be chained to each return results; this is in turn used by the handler to detect on a per-bind basis if the fetch strategy needs to do a SELECT or if it can do RETURNING. A test suite is added to test_horizontal_shard that breaks up a single UPDATE or DELETE operation among multiple backends where some are SQLite and don't support RETURNING and others are PostgreSQL and do. The session event mechanics are corrected in terms of the "orm pre execute" hook, which now receives a flag "is_reentrant" so that the two ORM implementations for this can skip on their work if they are being called inside of ORMExecuteState.invoke(), where previously bulk update/delete were calling its SELECT a second time. In order for "fetch" to get the correct identity when called as pre-execute, it also requests the identity_token for each mapped instance which is now added as an optional capability of a SELECT for ORM columns. the identity_token that's placed by horizontal_sharding is now made available within each result row, so that even when fetching a merged result of plain rows we can tell which row belongs to which identity token. The evaluator that takes place within the ORM bulk update and delete for synchronize_session="evaluate" now supports the IN and NOT IN operators. Tuple IN is also supported. Fixes: #1653 Change-Id: I2292b56ae004b997cef0ba4d3fc350ae1dd5efc1
* Turn on caching everywhere, add loggingMike Bayer2020-06-101-8/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Add support for "real" sequences in mssqlGord Thompson2020-05-291-0/+3
| | | | | | | | | | | | | | | | | Added support for "CREATE SEQUENCE" and full :class:`.Sequence` support for Microsoft SQL Server. This removes the deprecated feature of using :class:`.Sequence` objects to manipulate IDENTITY characteristics which should now be performed using ``mssql_identity_start`` and ``mssql_identity_increment`` as documented at :ref:`mssql_identity`. The change includes a new parameter :paramref:`.Sequence.data_type` to accommodate SQL Server's choice of datatype, which for that backend includes INTEGER and BIGINT. The default starting value for SQL Server's version of :class:`.Sequence` has been set at 1; this default is now emitted within the CREATE SEQUENCE DDL for all backends. Fixes: #4235 Fixes: #4633 Change-Id: I6aa55c441e8146c2f002e2e201a7f645e667b916
* callcount reductions and refinement for cached queriesMike Bayer2020-05-281-88/+78
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 Bayer2020-05-251-0/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Merge "Add with_for_update mysql new functionalities"mike bayer2020-05-231-0/+3
|\
| * Add with_for_update mysql new functionalitiesRobotScribe2020-05-151-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fixes: #4860 # Description Add nowait, skip_lock, of arguments to for_update_clause for mysql ### Checklist This pull request is: - [ ] A documentation / typographical error fix - Good to go, no issue or tests are needed - [ ] A short code fix - please include the issue number, and create an issue if none exists, which must include a complete example of the issue. one line code fixes without an issue and demonstration will not be accepted. - Please include: `Fixes: #<issue number>` in the commit message - please include tests. one line code fixes without tests will not be accepted. - [x] A new feature implementation - please include the issue number, and create an issue if none exists, which must include a complete example of how the feature would look. - Please include: `Fixes: #<issue number>` in the commit message - please include tests. **Have a nice day!** Closes: #5290 Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/5290 Pull-request-sha: 490e822e73e92ffe63cf45df9c49f3b31af1954d Change-Id: Ibd2acc47b538c601c69c8fb954776035ecab4c6c
* | Structural / performance refinementsMike Bayer2020-05-221-26/+9
| | | | | | | | | | | | | | | | | | | | | | | | * 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 Bayer2020-05-211-70/+61
| | | | | | | | | | | | | | | | | | | | | | 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
* | Disable "check unicode returns" under Python 3Mike Bayer2020-05-191-5/+16
|/ | | | | | | | | | | | | | | | | | | | | | | | | | Disabled the "unicode returns" check that runs on dialect startup when running under Python 3, which for many years has occurred in order to test the current DBAPI's behavior for whether or not it returns Python Unicode or Py2K strings for the VARCHAR and NVARCHAR datatypes. The check still occurs by default under Python 2, however the mechanism to test the behavior will be removed in SQLAlchemy 2.0 when Python 2 support is also removed. This logic was very effective when it was needed, however now that Python 3 is standard, all DBAPIs are expected to return Python 3 strings for character datatypes. In the unlikely case that a third party DBAPI does not support this, the conversion logic within :class:`.String` is still available and the third party dialect may specify this in its upfront dialect flags by setting the dialect level flag ``returns_unicode_strings`` to one of :attr:`.String.RETURNS_CONDITIONAL` or :attr:`.String.RETURNS_BYTES`, both of which will enable Unicode conversion even under Python 3. As part of this change, disabling testing of the doctest tutorials under Python 2. Fixes: #5315 Change-Id: I1260e894611409d3b7fe1a92bd90c52043bbcf19
* Propose Result as immediate replacement for ResultProxyMike Bayer2020-05-011-11/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Create initial 2.0 engine implementationMike Bayer2020-04-161-23/+104
| | | | | | | | | | | | | | | | | | | 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 Bayer2020-04-141-3/+3
| | | | | | | includes more replacements for create_engine(), Connection, disambiguation of Result from future/baked Change-Id: Icb60a79ee7a6c45ea9056c211ffd1be110da3b5e
* Run search and replace of symbolic module namesMike Bayer2020-04-141-5/+8
| | | | | | | | 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 Caselli2020-04-091-11/+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
* Broaden is[not]_distinct_from supportGord Thompson2020-04-021-0/+2
| | | | | | | Added support for .is[not]_distinct_from to SQL Server, MySQL, and Oracle. Fixes: #5137 Change-Id: I3b4d3b199821a55687f83c9a5b63a95d07a64cd5
* Try to measure new style caching in the ORM, take twoMike Bayer2020-04-011-5/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* String compiler can now literal compile datetime objectsFederico Caselli2020-03-291-0/+26
| | | | | | | | | | Add ability to literal compile a :class:`DateTime`, :class:`Date` or :class:"Time" when using the string dialect for debugging purposes. This change does not impact real dialect implementation that retain their current behavior. Fixes: #5052 Change-Id: Ia3fad2be905c6d35b0106b9a2388c7508f067e90
* Convert schema_translate to a post compileMike Bayer2020-03-241-8/+19
| | | | | | | | | | | | | | | | 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
* Decouple compiler state from DML objects; make cacheableMike Bayer2020-03-061-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Targeting select / insert / update / delete, the goal is to minimize overhead of construction and generative methods so that only the raw arguments passed are handled. An interim stage that converts the raw state into more compiler-ready state is added, which is analogous to the ORM QueryContext which will also be rolled in to be a similar concept, as is currently being prototyped in I19e05b3424b07114cce6c439b05198ac47f7ac10. the ORM update/delete BulkUD concept is also going to be rolled onto this idea. So while the compiler-ready state object, here called DMLState, looks a little thin, it's the base of a bigger pattern that will allow for ORM functionality to embed itself directly into the compiler, execution context, and result set objects. This change targets the DML objects, primarily focused on the values() method which is the most complex process. The work done by values() is minimized as much as possible while still being able to create a cache key. Additional computation is then offloaded to a new object ValuesState that is handled by the compiler. Architecturally, a big change here is that insert.values() and update.values() will generate BindParameter objects for the values now, which are then carefully received by crud.py so that they generate the expected names. This is so that the values() portion of these constructs is cacheable. for the "multi-values" version of Insert, this is all skipped and the plan right now is that a multi-values insert is not worth caching (can always be revisited). Using the coercions system in values() also gets us nicer validation for free, we can remove the NotAClauseElement thing from schema, and we also now require scalar_subquery() is called for an insert/update that uses a SELECT as a column value, 1.x deprecation path is added. The traversal system is then applied to the DML objects including tests so that they have traversal, cloning, and cache key support. cloning is not a use case for DML however having it present allows better validation of the structure within the tests. Special per-dialect DML is explicitly not cacheable at the moment, more as a proof of concept that third party DML constructs can exist as gracefully not-cacheable rather than producing an incomplete cache key. A few selected performance improvements have been added as well, simplifying the immutabledict.union() method and adding a new SQLCompiler function that can generate delimeter-separated clauses like WHERE and ORDER BY without having to build a ClauseList object at all. The use of ClauseList will be removed from Select in an upcoming commit. Overall, ClaustList is unnecessary for internal use and only adds overhead to statement construction and will likely be removed as much as possible except for explcit use of conjunctions like and_() and or_(). Change-Id: I408e0b8be91fddd77cf279da97f55020871f75a9
* Don't import provision.py unconditionallyMike Bayer2020-03-031-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | 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
* Update dialect API documentationMike Bayer2020-03-021-11/+3
| | | | | | | | | | The docstrings for connect() and on_connect() were incorrect between Dialect vs. DefaultDialect. Redocumented related methods, clean up formatting, and remove unicode-related attribute descriptions from the top level Dialect document as these don't apply to Python 3. Change-Id: I45baab757f8e20627eba42c30b9e8dbe26356275
* Result initial introductionMike Bayer2020-02-211-26/+88
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 Bayer2020-02-211-21/+55
| | | | | | | | | | | | | | | 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
* Create initial future package, RemovedIn20WarningMike Bayer2020-02-121-0/+1
| | | | | | | | | | | | | | | | | 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
* Query linter optionAlessio Bogon2020-01-221-2/+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
* Remove jython code, remove all jython / pypy symbolsMike Bayer2020-01-171-3/+1
| | | | | | | | | | | | | | | | | | | | | | Removed all dialect code related to support for Jython and zxJDBC. Jython has not been supported by SQLAlchemy for many years and it is not expected that the current zxJDBC code is at all functional; for the moment it just takes up space and adds confusion by showing up in documentation. At the moment, it appears that Jython has achieved Python 2.7 support in its releases but not Python 3. If Jython were to be supported again, the form it should take is against the Python 3 version of Jython, and the various zxJDBC stubs for various backends should be implemented as a third party dialect. Additionally modernized logic that distinguishes between "cpython" and "pypy" to instead look at platform.python_distribution() which reliably tells us if we are cPython or not; all booleans which previously checked for pypy and sometimes jython are now converted to be "not cpython", this impacts the test suite for tests that are cPython centric. Fixes: #5094 Change-Id: I226cb55827f997daf6b4f4a755c18e7f4eb8d9ad
* happy new yearMike Bayer2020-01-011-1/+1
| | | | Change-Id: I08440dc25e40ea1ccea1778f6ee9e28a00808235
View Lorry Controller Status