<feed xmlns='http://www.w3.org/2005/Atom'>
<title>delta/python-packages/sqlalchemy.git/lib/sqlalchemy/engine/default.py, branch rel_2_0_6</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 event handlers called for all do_ping</title>
<updated>2023-03-04T16:00:48+00:00</updated>
<author>
<name>Mike Bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2023-02-24T21:15:21+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=5132237f8ddaab1a8c6bfcaa03aca6487434ae95'/>
<id>5132237f8ddaab1a8c6bfcaa03aca6487434ae95</id>
<content type='text'>
The support for pool ping listeners to receive exception events via the
:meth:`.ConnectionEvents.handle_error` event added in 2.0.0b1 for
:ticket:`5648` failed to take into account dialect-specific ping routines
such as that of MySQL and PostgreSQL. The dialect feature has been reworked
so that all dialects participate within event handling.   Additionally,
a new boolean element :attr:`.ExceptionContext.is_pre_ping` is added
which identifies if this operation is occurring within the pre-ping
operation.

For this release, third party dialects which implement a custom
:meth:`_engine.Dialect.do_ping` method can opt in to the newly improved
behavior by having their method no longer catch exceptions or check
exceptions for "is_disconnect", instead just propagating all exceptions
outwards. Checking the exception for "is_disconnect" is now done by an
enclosing method on the default dialect, which ensures that the event hook
is invoked for all exception scenarios before testing the exception as a
"disconnect" exception. If an existing ``do_ping()`` method continues to
catch exceptions and check "is_disconnect", it will continue to work as it
did previously, but ``handle_error`` hooks will not have access to the
exception if it isn't propagated outwards.

Fixes: #5648
Change-Id: I6535d5cb389e1a761aad8c37cfeb332c548b876d
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The support for pool ping listeners to receive exception events via the
:meth:`.ConnectionEvents.handle_error` event added in 2.0.0b1 for
:ticket:`5648` failed to take into account dialect-specific ping routines
such as that of MySQL and PostgreSQL. The dialect feature has been reworked
so that all dialects participate within event handling.   Additionally,
a new boolean element :attr:`.ExceptionContext.is_pre_ping` is added
which identifies if this operation is occurring within the pre-ping
operation.

For this release, third party dialects which implement a custom
:meth:`_engine.Dialect.do_ping` method can opt in to the newly improved
behavior by having their method no longer catch exceptions or check
exceptions for "is_disconnect", instead just propagating all exceptions
outwards. Checking the exception for "is_disconnect" is now done by an
enclosing method on the default dialect, which ensures that the event hook
is invoked for all exception scenarios before testing the exception as a
"disconnect" exception. If an existing ``do_ping()`` method continues to
catch exceptions and check "is_disconnect", it will continue to work as it
did previously, but ``handle_error`` hooks will not have access to the
exception if it isn't propagated outwards.

Fixes: #5648
Change-Id: I6535d5cb389e1a761aad8c37cfeb332c548b876d
</pre>
</div>
</content>
</entry>
<entry>
<title>replace @decorated_property decorator</title>
<updated>2023-01-12T17:36:25+00:00</updated>
<author>
<name>Mike Bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2023-01-12T17:33:09+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=ae7e74487e5aff1b9ebb832a704055ddcf042567'/>
<id>ae7e74487e5aff1b9ebb832a704055ddcf042567</id>
<content type='text'>
This decorator is no longer necessary as of Mypy
0.981 [1].

In current mypy versions, we require direct use of
`@property` for return types of these methods to be
recognized

[1] https://github.com/python/mypy/issues/1362

Change-Id: Ibc36083dec854c5f9140a9b621e9bf9d5bb4fb61
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This decorator is no longer necessary as of Mypy
0.981 [1].

In current mypy versions, we require direct use of
`@property` for return types of these methods to be
recognized

[1] https://github.com/python/mypy/issues/1362

Change-Id: Ibc36083dec854c5f9140a9b621e9bf9d5bb4fb61
</pre>
</div>
</content>
</entry>
<entry>
<title>happy new year 2023</title>
<updated>2023-01-03T17:45:52+00:00</updated>
<author>
<name>Mike Bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2023-01-03T17:45:52+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=5147bf8e3cb321b8728b3af5bb0b2644995b3793'/>
<id>5147bf8e3cb321b8728b3af5bb0b2644995b3793</id>
<content type='text'>
Change-Id: I625af65b3fb1815b1af17dc2ef47dd697fdc3fb1
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Change-Id: I625af65b3fb1815b1af17dc2ef47dd697fdc3fb1
</pre>
</div>
</content>
</entry>
<entry>
<title>Rewrite positional handling, test for "numeric"</title>
<updated>2022-12-05T14:59:01+00:00</updated>
<author>
<name>Federico Caselli</name>
<email>cfederico87@gmail.com</email>
</author>
<published>2022-12-02T16:58:40+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=06c234d037bdab48e716d6c5f5dc200095269474'/>
<id>06c234d037bdab48e716d6c5f5dc200095269474</id>
<content type='text'>
Changed how the positional compilation is performed. It's rendered by the compiler
the same as the pyformat compilation. The string is then processed to replace
the placeholders with the correct ones, and to obtain the correct order of the
parameters.
This vastly simplifies the computation of the order of the parameters, that in
case of nested CTE is very hard to compute correctly.

Reworked how numeric paramstyle behavers:
- added support for repeated parameter, without duplicating them like in normal
positional dialects
- implement insertmany support. This requires that the dialect supports out of
order placehoders, since all parameters that are not part of the VALUES clauses
are placed at the beginning of the parameter tuple
- support for different identifiers for a numeric parameter. It's for example
possible to use postgresql style placeholder $1, $2, etc

Added two new dialect based on sqlite to test "numeric" fully using
both :1 style and $1 style. Includes a workaround for SQLite's
not-really-correct numeric implementation.

Changed parmstyle of asyncpg dialect to use numeric, rendering with its native
$ identifiers

Fixes: #8926
Fixes: #8849
Change-Id: I7c640467d49adfe6d795cc84296fc7403dcad4d6
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Changed how the positional compilation is performed. It's rendered by the compiler
the same as the pyformat compilation. The string is then processed to replace
the placeholders with the correct ones, and to obtain the correct order of the
parameters.
This vastly simplifies the computation of the order of the parameters, that in
case of nested CTE is very hard to compute correctly.

Reworked how numeric paramstyle behavers:
- added support for repeated parameter, without duplicating them like in normal
positional dialects
- implement insertmany support. This requires that the dialect supports out of
order placehoders, since all parameters that are not part of the VALUES clauses
are placed at the beginning of the parameter tuple
- support for different identifiers for a numeric parameter. It's for example
possible to use postgresql style placeholder $1, $2, etc

Added two new dialect based on sqlite to test "numeric" fully using
both :1 style and $1 style. Includes a workaround for SQLite's
not-really-correct numeric implementation.

Changed parmstyle of asyncpg dialect to use numeric, rendering with its native
$ identifiers

Fixes: #8926
Fixes: #8849
Change-Id: I7c640467d49adfe6d795cc84296fc7403dcad4d6
</pre>
</div>
</content>
</entry>
<entry>
<title>Try running pyupgrade on the code</title>
<updated>2022-11-16T22:03:04+00:00</updated>
<author>
<name>Federico Caselli</name>
<email>cfederico87@gmail.com</email>
</author>
<published>2022-11-03T19:52:21+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=4eb4ceca36c7ce931ea65ac06d6ed08bf459fc66'/>
<id>4eb4ceca36c7ce931ea65ac06d6ed08bf459fc66</id>
<content type='text'>
command run is "pyupgrade --py37-plus --keep-runtime-typing --keep-percent-format &lt;files...&gt;"
pyupgrade will change assert_ to assertTrue. That was reverted since assertTrue does not
exists in sqlalchemy fixtures

Change-Id: Ie1ed2675c7b11d893d78e028aad0d1576baebb55
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
command run is "pyupgrade --py37-plus --keep-runtime-typing --keep-percent-format &lt;files...&gt;"
pyupgrade will change assert_ to assertTrue. That was reverted since assertTrue does not
exists in sqlalchemy fixtures

Change-Id: Ie1ed2675c7b11d893d78e028aad0d1576baebb55
</pre>
</div>
</content>
</entry>
<entry>
<title>Improve typings of execution options</title>
<updated>2022-11-03T01:38:31+00:00</updated>
<author>
<name>Federico Caselli</name>
<email>cfederico87@gmail.com</email>
</author>
<published>2022-10-17T20:02:13+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=d10b62f54e6b9dd0613c0412b924c1b346ec1611'/>
<id>d10b62f54e6b9dd0613c0412b924c1b346ec1611</id>
<content type='text'>
Fixes: #8605
Change-Id: I4aec83b9f321462427c3f4ac941c3b272255c088
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fixes: #8605
Change-Id: I4aec83b9f321462427c3f4ac941c3b272255c088
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert automatic set of sequence start to 1</title>
<updated>2022-10-17T19:36:25+00:00</updated>
<author>
<name>Federico Caselli</name>
<email>cfederico87@gmail.com</email>
</author>
<published>2022-09-24T13:50:26+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=974b1bd0fc40e11fc2886b5a9fc333feeeebf546'/>
<id>974b1bd0fc40e11fc2886b5a9fc333feeeebf546</id>
<content type='text'>
The :class:`.Sequence` construct restores itself to the DDL behavior it
had prior to the 1.4 series, where creating a :class:`.Sequence` with
no additional arguments will emit a simple ``CREATE SEQUENCE`` instruction
**without** any additional parameters for "start value".   For most backends,
this is how things worked previously in any case; **however**, for
MS SQL Server, the default value on this database is
``-2**63``; to prevent this generally impractical default
from taking effect on SQL Server, the :paramref:`.Sequence.start` parameter
should be provided.   As usage of :class:`.Sequence` is unusual
for SQL Server which for many years has standardized on ``IDENTITY``,
it is hoped that this change has minimal impact.

Fixes: #7211
Change-Id: I1207ea10c8cb1528a1519a0fb3581d9621c27b31
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The :class:`.Sequence` construct restores itself to the DDL behavior it
had prior to the 1.4 series, where creating a :class:`.Sequence` with
no additional arguments will emit a simple ``CREATE SEQUENCE`` instruction
**without** any additional parameters for "start value".   For most backends,
this is how things worked previously in any case; **however**, for
MS SQL Server, the default value on this database is
``-2**63``; to prevent this generally impractical default
from taking effect on SQL Server, the :paramref:`.Sequence.start` parameter
should be provided.   As usage of :class:`.Sequence` is unusual
for SQL Server which for many years has standardized on ``IDENTITY``,
it is hoped that this change has minimal impact.

Fixes: #7211
Change-Id: I1207ea10c8cb1528a1519a0fb3581d9621c27b31
</pre>
</div>
</content>
</entry>
<entry>
<title>ORM bulk insert via execute</title>
<updated>2022-09-24T15:18:01+00:00</updated>
<author>
<name>Mike Bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2022-08-07T16:14:19+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=a8029f5a7e3e376ec57f1614ab0294b717d53c05'/>
<id>a8029f5a7e3e376ec57f1614ab0294b717d53c05</id>
<content type='text'>
* ORM Insert now includes "bulk" mode that will run
  essentially the same process as session.bulk_insert_mappings;
  interprets the given list of values as ORM attributes for
  key names
* ORM UPDATE has a similar feature, without RETURNING support,
  for session.bulk_update_mappings
* Added support for upserts to do RETURNING ORM objects as well
* ORM UPDATE/DELETE with list of parameters + WHERE criteria
  is a not implemented; use connection
* ORM UPDATE/DELETE defaults to "auto" synchronize_session;
  use fetch if RETURNING is present, evaluate if not, as
  "fetch" is much more efficient (no expired object SELECT problem)
  and less error prone if RETURNING is available
  UPDATE: howver this is inefficient!   please continue to
  use evaluate for simple cases, auto can move to fetch
  if criteria not evaluable
* "Evaluate" criteria will now not preemptively
  unexpire and SELECT attributes that were individually
  expired. Instead, if evaluation of the criteria indicates that
  the necessary attrs were expired, we expire the object
  completely (delete) or expire the SET attrs unconditionally
  (update). This keeps the object in the same unloaded state
  where it will refresh those attrs on the next pass, for
  this generally unusual case.  (originally #5664)
* Core change! update/delete rowcount comes from len(rows)
  if RETURNING was used.  SQLite at least otherwise did not
  support this.  adjusted test_rowcount accordingly
* ORM DELETE with a list of parameters at all is also a not
  implemented as this would imply "bulk", and there is no
  bulk_delete_mappings (could be, but we dont have that)
* ORM insert().values() with single or multi-values translates
  key names based on ORM attribute names
* ORM returning() implemented for insert, update, delete;
  explcit returning clauses now interpret rows in an ORM
  context, with support for qualifying loader options as well
* session.bulk_insert_mappings() assigns polymorphic identity
  if not set.
* explicit RETURNING + synchronize_session='fetch' is now
  supported with UPDATE and DELETE.
* expanded return_defaults() to work with DELETE also.
* added support for composite attributes to be present
  in the dictionaries used by bulk_insert_mappings and
  bulk_update_mappings, which is also the new ORM bulk
  insert/update feature, that will expand the composite
  values into their individual mapped attributes the way they'd
  be on a mapped instance.
* bulk UPDATE supports "synchronize_session=evaluate", is the
  default.  this does not apply to session.bulk_update_mappings,
  just the new version
* both bulk UPDATE and bulk INSERT, the latter with or without
  RETURNING, support *heterogenous* parameter sets.
  session.bulk_insert/update_mappings did this, so this feature
  is maintained.  now cursor result can be both horizontally
  and vertically spliced :)

This is now a long story with a lot of options, which in
itself is a problem to be able to document all of this
in some way that makes sense.  raising exceptions for
use cases we haven't supported is pretty important here
too, the tradition of letting unsupported things just not work
is likely not a good idea at this point, though there
are still many cases that aren't easily avoidable

Fixes: #8360
Fixes: #7864
Fixes: #7865
Change-Id: Idf28379f8705e403a3c6a937f6a798a042ef2540
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* ORM Insert now includes "bulk" mode that will run
  essentially the same process as session.bulk_insert_mappings;
  interprets the given list of values as ORM attributes for
  key names
* ORM UPDATE has a similar feature, without RETURNING support,
  for session.bulk_update_mappings
* Added support for upserts to do RETURNING ORM objects as well
* ORM UPDATE/DELETE with list of parameters + WHERE criteria
  is a not implemented; use connection
* ORM UPDATE/DELETE defaults to "auto" synchronize_session;
  use fetch if RETURNING is present, evaluate if not, as
  "fetch" is much more efficient (no expired object SELECT problem)
  and less error prone if RETURNING is available
  UPDATE: howver this is inefficient!   please continue to
  use evaluate for simple cases, auto can move to fetch
  if criteria not evaluable
* "Evaluate" criteria will now not preemptively
  unexpire and SELECT attributes that were individually
  expired. Instead, if evaluation of the criteria indicates that
  the necessary attrs were expired, we expire the object
  completely (delete) or expire the SET attrs unconditionally
  (update). This keeps the object in the same unloaded state
  where it will refresh those attrs on the next pass, for
  this generally unusual case.  (originally #5664)
* Core change! update/delete rowcount comes from len(rows)
  if RETURNING was used.  SQLite at least otherwise did not
  support this.  adjusted test_rowcount accordingly
* ORM DELETE with a list of parameters at all is also a not
  implemented as this would imply "bulk", and there is no
  bulk_delete_mappings (could be, but we dont have that)
* ORM insert().values() with single or multi-values translates
  key names based on ORM attribute names
* ORM returning() implemented for insert, update, delete;
  explcit returning clauses now interpret rows in an ORM
  context, with support for qualifying loader options as well
* session.bulk_insert_mappings() assigns polymorphic identity
  if not set.
* explicit RETURNING + synchronize_session='fetch' is now
  supported with UPDATE and DELETE.
* expanded return_defaults() to work with DELETE also.
* added support for composite attributes to be present
  in the dictionaries used by bulk_insert_mappings and
  bulk_update_mappings, which is also the new ORM bulk
  insert/update feature, that will expand the composite
  values into their individual mapped attributes the way they'd
  be on a mapped instance.
* bulk UPDATE supports "synchronize_session=evaluate", is the
  default.  this does not apply to session.bulk_update_mappings,
  just the new version
* both bulk UPDATE and bulk INSERT, the latter with or without
  RETURNING, support *heterogenous* parameter sets.
  session.bulk_insert/update_mappings did this, so this feature
  is maintained.  now cursor result can be both horizontally
  and vertically spliced :)

This is now a long story with a lot of options, which in
itself is a problem to be able to document all of this
in some way that makes sense.  raising exceptions for
use cases we haven't supported is pretty important here
too, the tradition of letting unsupported things just not work
is likely not a good idea at this point, though there
are still many cases that aren't easily avoidable

Fixes: #8360
Fixes: #7864
Fixes: #7865
Change-Id: Idf28379f8705e403a3c6a937f6a798a042ef2540
</pre>
</div>
</content>
</entry>
<entry>
<title>implement batched INSERT..VALUES () () for executemany</title>
<updated>2022-09-24T15:15:32+00:00</updated>
<author>
<name>Mike Bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2022-07-18T19:08:37+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=2bcc97da424eef7db9a5d02f81d02344925415ee'/>
<id>2bcc97da424eef7db9a5d02f81d02344925415ee</id>
<content type='text'>
the feature is enabled for all built in backends
when RETURNING is used,
except for Oracle that doesn't need it,  and on
psycopg2 and mssql+pyodbc it is used for all INSERT statements,
not just those that use RETURNING.

third party dialects would need to opt in to the new feature
by setting use_insertmanyvalues to True.

Also adds dialect-level guards against using returning
with executemany where we dont have an implementation to
suit it.   execute single w/ returning still defers to the
server without us checking.

Fixes: #6047
Fixes: #7907
Change-Id: I3936d3c00003f02e322f2e43fb949d0e6e568304
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
the feature is enabled for all built in backends
when RETURNING is used,
except for Oracle that doesn't need it,  and on
psycopg2 and mssql+pyodbc it is used for all INSERT statements,
not just those that use RETURNING.

third party dialects would need to opt in to the new feature
by setting use_insertmanyvalues to True.

Also adds dialect-level guards against using returning
with executemany where we dont have an implementation to
suit it.   execute single w/ returning still defers to the
server without us checking.

Fixes: #6047
Fixes: #7907
Change-Id: I3936d3c00003f02e322f2e43fb949d0e6e568304
</pre>
</div>
</content>
</entry>
<entry>
<title>break out text() from TextualSelect for col matching</title>
<updated>2022-09-19T22:39:18+00:00</updated>
<author>
<name>Mike Bayer</name>
<email>mike_mp@zzzcomputing.com</email>
</author>
<published>2022-09-19T13:40:40+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/python-packages/sqlalchemy.git/commit/?id=c9af2ebf5e5d288aea3a3a26bdf950e08ac4f927'/>
<id>c9af2ebf5e5d288aea3a3a26bdf950e08ac4f927</id>
<content type='text'>
Fixed issue where mixing "*" with additional explicitly-named column
expressions within the columns clause of a :func:`_sql.select` construct
would cause result-column targeting to sometimes consider the label name or
other non-repeated names to be an ambiguous target.

Fixes: #8536
Change-Id: I3c845eaf571033e54c9208762344f67f4351ac3a
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fixed issue where mixing "*" with additional explicitly-named column
expressions within the columns clause of a :func:`_sql.select` construct
would cause result-column targeting to sometimes consider the label name or
other non-repeated names to be an ambiguous target.

Fixes: #8536
Change-Id: I3c845eaf571033e54c9208762344f67f4351ac3a
</pre>
</div>
</content>
</entry>
</feed>
