:meth:`.ConnectionEvents.detach`, :meth:`.ConnectionEvents.close_detached`.
via :paramref:`.create_engine.isolation_level` and :paramref:`.Connection.execution_options.isolation_level` parameters. fixes #3534
for example an exception object made within a test suite can still repr (error seen in Keystone)
logging, exception, and ``repr()`` purposes now truncate very large scalar values within each collection, including an "N characters truncated" notation, similar to how the display for large multiple-parameter sets are themselves truncated. fixes #2837
the warning here to all safe_reraise() cases in Python 2. - Revisiting :ticket:`2696`, first released in 1.0.10, which attempts to work around Python 2's lack of exception context reporting by emitting a warning for an exception that was interrupted by a second exception when attempting to roll back the already-failed transaction; this issue continues to occur for MySQL backends in conjunction with a savepoint that gets unexpectedly lost, which then causes a "no such savepoint" error when the rollback is attempted, obscuring what the original condition was. The approach has been generalized to the Core "safe reraise" function which takes place across the ORM and Core in any place that a transaction is being rolled back in response to an error which occurred trying to commit, including the context managers provided by :class:`.Session` and :class:`.Connection`, and taking place for operations such as a failure on "RELEASE SAVEPOINT". Previously, the fix was only in place for a specific path within the ORM flush/commit process; it now takes place for all transational context managers as well. fixes #2696
This supports the use case of an application that uses the same set of
:class:`.Table` objects in many schemas, such as schema-per-user.
A new execution option
:paramref:`.Connection.execution_options.schema_translate_map` is
added. fixes #2685
- latest tox doesn't like the {posargs} in the profile rerunner
be stated in the query string for a URL. Custom plugins can be written which will be given the chance up front to alter and/or consume the engine's URL and keyword arguments, and then at engine create time will be given the engine itself to allow additional modifications or event registration. Plugins are written as a subclass of :class:`.CreateEnginePlugin`; see that class for details. fixes #3536
"auto increment" column has been changed, such that autoincrement is no longer implicitly enabled for a :class:`.Table` that has a composite primary key. In order to accommodate being able to enable autoincrement for a composite PK member column while at the same time maintaining SQLAlchemy's long standing behavior of enabling implicit autoincrement for a single integer primary key, a third state has been added to the :paramref:`.Column.autoincrement` parameter ``"auto"``, which is now the default. fixes #3216 - The MySQL dialect no longer generates an extra "KEY" directive when generating CREATE TABLE DDL for a table using InnoDB with a composite primary key with AUTO_INCREMENT on a column that isn't the first column; to overcome InnoDB's limitation here, the PRIMARY KEY constraint is now generated with the AUTO_INCREMENT column placed first in the list of columns.