<feed xmlns='http://www.w3.org/2005/Atom'>
<title>delta/python-packages/sqlalchemy.git/lib/sqlalchemy/engine/cursor.py, branch review/mike_bayer/tutorial20</title>
<subtitle>github.com: zzzeek/sqlalchemy.git
</subtitle>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/'/>
<entry>
<title>Ensure all cursor self.handle_exception() calls are covered</title>
<updated>2020-10-12T16:31:10+00:00</updated>
<author>
<name>Mike Bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2020-10-12T14:16:25+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=286fe9b0b165e46099066cc16552b93a0b853a7e'/>
<id>286fe9b0b165e46099066cc16552b93a0b853a7e</id>
<content type='text'>
Fixes: #5642
Change-Id: I07a77483e6e2ec593d87d3d3467a4339c5f77a26
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fixes: #5642
Change-Id: I07a77483e6e2ec593d87d3d3467a4339c5f77a26
</pre>
</div>
</content>
</entry>
<entry>
<title>upgrade to black 20.8b1</title>
<updated>2020-09-28T19:17:26+00:00</updated>
<author>
<name>Mike Bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2020-09-28T18:08:59+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=c3f102c9fe9811fd5286628cc6aafa5fbc324621'/>
<id>c3f102c9fe9811fd5286628cc6aafa5fbc324621</id>
<content type='text'>
It's better, the majority of these changes look more readable to me.
also found some docstrings that had formatting / quoting issues.

Change-Id: I582a45fde3a5648b2f36bab96bad56881321899b
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
It's better, the majority of these changes look more readable to me.
also found some docstrings that had formatting / quoting issues.

Change-Id: I582a45fde3a5648b2f36bab96bad56881321899b
</pre>
</div>
</content>
</entry>
<entry>
<title>Don't rely on string col name in adapt_to_context</title>
<updated>2020-09-06T13:55:27+00:00</updated>
<author>
<name>Mike Bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2020-09-05T23:45:04+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=b0e9083eb2a786670a1a129d7968d768d1c4ab42'/>
<id>b0e9083eb2a786670a1a129d7968d768d1c4ab42</id>
<content type='text'>
fixed an issue where even though the method claims to be
matching up columns positionally, it was failing on that by
looking in "keymap" based on string name.

Adds a new member to the _keymap recs MD_RESULT_MAP_INDEX
so that we can efficiently link from the generated keymap
back to the compiled._result_columns structure without
any ambiguity.

Fixes: #5559

Change-Id: Ie2fa9165c16625ef860ffac1190e00575e96761f
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
fixed an issue where even though the method claims to be
matching up columns positionally, it was failing on that by
looking in "keymap" based on string name.

Adds a new member to the _keymap recs MD_RESULT_MAP_INDEX
so that we can efficiently link from the generated keymap
back to the compiled._result_columns structure without
any ambiguity.

Fixes: #5559

Change-Id: Ie2fa9165c16625ef860ffac1190e00575e96761f
</pre>
</div>
</content>
</entry>
<entry>
<title>Break scalars() and mappings() into separate objects</title>
<updated>2020-08-12T16:23:56+00:00</updated>
<author>
<name>Mike Bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2020-08-10T22:40:49+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=6d4dcbb40571644494524738cd76e2e281323534'/>
<id>6d4dcbb40571644494524738cd76e2e281323534</id>
<content type='text'>
The issue of Result.fetchXXX()  methods returning Row
objects unless filtering is applied will not provide a
clear enough API story when type annotations are applied,
so break out scalars/mappings into separate wrapper objects.
this makes some things more intuitive and other things a little
more bumpy.   however the return type story is now clearer.

Fixes: #5503
Change-Id: I629a061823179680dc0723559183859a67ea4db1
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The issue of Result.fetchXXX()  methods returning Row
objects unless filtering is applied will not provide a
clear enough API story when type annotations are applied,
so break out scalars/mappings into separate wrapper objects.
this makes some things more intuitive and other things a little
more bumpy.   however the return type story is now clearer.

Fixes: #5503
Change-Id: I629a061823179680dc0723559183859a67ea4db1
</pre>
</div>
</content>
</entry>
<entry>
<title>Robustness for lambdas, lambda statements</title>
<updated>2020-08-05T20:42:26+00:00</updated>
<author>
<name>Mike Bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2020-08-05T20:42:26+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=cc57ea495f6460dd56daa6de57e40047ed999369'/>
<id>cc57ea495f6460dd56daa6de57e40047ed999369</id>
<content type='text'>
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
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge "Fix a wide variety of typos and broken links"</title>
<updated>2020-06-26T15:30:57+00:00</updated>
<author>
<name>mike bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2020-06-26T15:30:57+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=ba047cc8cab22541e88ce91936162d6e8164991a'/>
<id>ba047cc8cab22541e88ce91936162d6e8164991a</id>
<content type='text'>
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
</pre>
</div>
</content>
</entry>
<entry>
<title>Fix a wide variety of typos and broken links</title>
<updated>2020-06-25T23:42:28+00:00</updated>
<author>
<name>aplatkouski</name>
<email>5857672+aplatkouski@users.noreply.github.com</email>
</author>
<published>2020-06-22T15:34:39+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=2a1a9f5f5a9723f757439657d2bdf224baed8748'/>
<id>2a1a9f5f5a9723f757439657d2bdf224baed8748</id>
<content type='text'>
Note the PR has a few remaining doc linking issues
listed in the comment that must be addressed separately.

Signed-off-by: aplatkouski &lt;5857672+aplatkouski@users.noreply.github.com&gt;
Closes: #5371
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/5371
Pull-request-sha: 7e7d233cf3a0c66980c27db0fcdb3c7d93bc2510

Change-Id: I9c36e8d8804483950db4b42c38ee456e384c59e3
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Note the PR has a few remaining doc linking issues
listed in the comment that must be addressed separately.

Signed-off-by: aplatkouski &lt;5857672+aplatkouski@users.noreply.github.com&gt;
Closes: #5371
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/5371
Pull-request-sha: 7e7d233cf3a0c66980c27db0fcdb3c7d93bc2510

Change-Id: I9c36e8d8804483950db4b42c38ee456e384c59e3
</pre>
</div>
</content>
</entry>
<entry>
<title>Default psycopg2 executemany mode to "values_only"</title>
<updated>2020-06-25T22:58:34+00:00</updated>
<author>
<name>Mike Bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2020-06-23T20:21:04+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=f1a3038f480ee1965928cdcd1dc0c47347f270bc'/>
<id>f1a3038f480ee1965928cdcd1dc0c47347f270bc</id>
<content type='text'>
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
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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
</pre>
</div>
</content>
</entry>
<entry>
<title>Turn on caching everywhere, add logging</title>
<updated>2020-06-10T19:29:01+00:00</updated>
<author>
<name>Mike Bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2020-06-07T00:40:43+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=b0cfa7379cf8513a821a3dbe3028c4965d9f85bd'/>
<id>b0cfa7379cf8513a821a3dbe3028c4965d9f85bd</id>
<content type='text'>
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
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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
</pre>
</div>
</content>
</entry>
<entry>
<title>Convert bulk update/delete to new execution model</title>
<updated>2020-06-06T17:31:54+00:00</updated>
<author>
<name>Mike Bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2020-06-03T21:38:35+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=3ab2364e78641c4f0e4b6456afc2cbed39b0d0e6'/>
<id>3ab2364e78641c4f0e4b6456afc2cbed39b0d0e6</id>
<content type='text'>
This reorganizes the BulkUD model in sqlalchemy.orm.persistence
to be based on the CompileState concept and to allow plain
update() / delete() to be passed to session.execute() where
the ORM synchronize session logic will take place.
Also gets "synchronize_session='fetch'" working with horizontal
sharding.

Adding a few more result.scalar_one() types of methods
as scalar_one() seems like what is normally desired.

Fixes: #5160
Change-Id: I8001ebdad089da34119eb459709731ba6c0ba975
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This reorganizes the BulkUD model in sqlalchemy.orm.persistence
to be based on the CompileState concept and to allow plain
update() / delete() to be passed to session.execute() where
the ORM synchronize session logic will take place.
Also gets "synchronize_session='fetch'" working with horizontal
sharding.

Adding a few more result.scalar_one() types of methods
as scalar_one() seems like what is normally desired.

Fixes: #5160
Change-Id: I8001ebdad089da34119eb459709731ba6c0ba975
</pre>
</div>
</content>
</entry>
</feed>
