delta/python-packages/sqlalchemy.git/test/ext/test_deprecations.py, branch 2020_tutorial github.com: zzzeek/sqlalchemy.git callcount reductions and refinement for cached queries 2020-05-28T18:38:56+00:00 Mike Bayer mike_mp@zzzcomputing.com 2020-05-26T02:36:44+00:00 77f1b7d236dba6b1c859bb428ef32d118ec372e6 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 
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
Source base cleanups 2020-01-01T16:11:24+00:00 Mike Bayer mike_mp@zzzcomputing.com 2020-01-01T15:51:15+00:00 748bf710fdeeed327933a5e7c277c7f79f6053a6 in trying to apply 2020 copyright to files, the pre-commit hooks complain about random file issues. - remove old corrections.py utility, this had something to do with repairing refs in the sphinx docs - run pre commit hooks on all files - formatting adjustments to work around code formatting collisions (long import lines that zimports can't rewrite correctly) Change-Id: I260744866f69e902eb93665c7c728ee94d3371a2 
in trying to apply 2020 copyright to files, the pre-commit
hooks complain about random file issues.

- remove old corrections.py utility, this had something to do
  with repairing refs in the sphinx docs

- run pre commit hooks on all files

- formatting adjustments to work around code formatting collisions
  (long import lines that zimports can't rewrite correctly)

Change-Id: I260744866f69e902eb93665c7c728ee94d3371a2
Implement relationship to AliasedClass; deprecate non primary mappers 2019-01-25T14:28:28+00:00 Mike Bayer mike_mp@zzzcomputing.com 2018-12-30T01:54:29+00:00 93855ed623ceedffc02dee06c9a46c37dd26286b Implemented a new feature whereby the :class:`.AliasedClass` construct can now be used as the target of a :func:`.relationship`. This allows the concept of "non primary mappers" to no longer be necessary, as the :class:`.AliasedClass` is much easier to configure and automatically inherits all the relationships of the mapped class, as well as preserves the ability for loader options to work normally. - introduce new name for mapped_table, "persist_selectable". this is the selectable that selects against the local mapper and its superclasses, but does not include columns local only to subclasses. - relationship gains "entity" which is the mapper or aliasedinsp. - clarfiy name "entity" vs. "query_entity" in loader strategies. Fixes: #4423 Fixes: #4422 Fixes: #4421 Fixes: #3348 Change-Id: Ic3609b43dc4ed115006da9ad9189e574dc0c72d9 
Implemented a new feature whereby the :class:`.AliasedClass` construct can
now be used as the target of a :func:`.relationship`.  This allows the
concept of "non primary mappers" to no longer be necessary, as the
:class:`.AliasedClass` is much easier to configure and automatically inherits
all the relationships of the mapped class, as well as preserves the
ability for loader options to work normally.

- introduce new name for mapped_table, "persist_selectable".  this is
the selectable that selects against the local mapper and its superclasses,
but does not include columns local only to subclasses.

- relationship gains "entity" which is the mapper or aliasedinsp.

- clarfiy name "entity" vs. "query_entity" in loader strategies.

Fixes: #4423
Fixes: #4422
Fixes: #4421
Fixes: #3348

Change-Id: Ic3609b43dc4ed115006da9ad9189e574dc0c72d9