I faced an issue related to pg bouncer and prepared statement cache flow in asyncpg dialect. Regarding this discussion https://github.com/sqlalchemy/sqlalchemy/issues/6467 I prepared PR to support an optional parameter `name` in prepared statement which is allowed, since 0.25.0 version in `asyncpg` https://github.com/MagicStack/asyncpg/pull/846
**UPD:**
the issue with proposal: https://github.com/sqlalchemy/sqlalchemy/issues/9608
### Description
Added optional parameter `name_func` to `AsyncAdapt_asyncpg_connection` class which will call on the `self._connection.prepare()` function and populate a unique name.
so in general instead this
```python
from uuid import uuid4
from asyncpg import Connection
class CConnection(Connection):
def _get_unique_id(self, prefix: str) -> str:
return f'__asyncpg_{prefix}_{uuid4()}__'
engine = create_async_engine(...,
connect_args={
'connection_class': CConnection,
},
)
```
would be enough
```python
from uuid import uuid4
engine = create_async_engine(...,
connect_args={
'name_func': lambda: f'__asyncpg_{uuid4()}__',
},
)
```
### Checklist
<!-- go over following points. check them with an `x` if they do apply, (they turn into clickable checkboxes once the PR is submitted, so no need to do everything at once)
-->
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!**
Fixes: #9608
Closes: #9607
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/9607
Pull-request-sha: b4bc8d3e57ab095a26112830ad4bea36083454e3
Change-Id: Icd753366cba166b8a60d1c8566377ec8335cd828
Repaired a major shortcoming which was identified in the :ref:`engine_insertmanyvalues` performance optimization feature first introduced in the 2.0 series. This was a continuation of the change in 2.0.9 which disabled the SQL Server version of the feature due to a reliance in the ORM on apparent row ordering that is not guaranteed to take place. The fix applies new logic to all "insertmanyvalues" operations, which takes effect when a new parameter :paramref:`_dml.Insert.returning.sort_by_parameter_order` on the :meth:`_dml.Insert.returning` or :meth:`_dml.UpdateBase.return_defaults` methods, that through a combination of alternate SQL forms, direct correspondence of client side parameters, and in some cases downgrading to running row-at-a-time, will apply sorting to each batch of returned rows using correspondence to primary key or other unique values in each row which can be correlated to the input data. Performance impact is expected to be minimal as nearly all common primary key scenarios are suitable for parameter-ordered batching to be achieved for all backends other than SQLite, while "row-at-a-time" mode operates with a bare minimum of Python overhead compared to the very heavyweight approaches used in the 1.x series. For SQLite, there is no difference in performance when "row-at-a-time" mode is used. It's anticipated that with an efficient "row-at-a-time" INSERT with RETURNING batching capability, the "insertmanyvalues" feature can be later be more easily generalized to third party backends that include RETURNING support but not necessarily easy ways to guarantee a correspondence with parameter order. Fixes: #9618 References: #9603 Change-Id: I1d79353f5f19638f752936ba1c35e4dc235a8b7c
<!-- Provide a general summary of your proposed changes in the Title field above --> ### Description Fixes: #9509 <!-- Describe your changes in detail --> ### Checklist <!-- go over following points. check them with an `x` if they do apply, (they turn into clickable checkboxes once the PR is submitted, so no need to do everything at once) --> 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: #9510 Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/9510 Pull-request-sha: 596648e7989327eef1807057519b2295b48f1adf Change-Id: I7b527edda09eb78dee6948edd4d49b00ea437011
Restored the :paramref:`_postgresql.ENUM.name` parameter as optional in the signature for :class:`_postgresql.ENUM`, as this is chosen automatically from a given pep-435 ``Enum`` type. Fixed issue where the comparison for :class:`_postgresql.ENUM` against a plain string would cast that right-hand side type as VARCHAR, which due to more explicit casting added to dialects such as asyncpg would produce a PostgreSQL type mismatch error. Fixes: #9611 Fixes: #9621 Change-Id: If095544cd1a52016ad2e7cfa2d70c919a94e79c1
Change-Id: If6f2efd7cd443593a8e7ca06109e51cfd07ed020
we will keep trying to find workarounds, however this patch is the "turn it off" patch Due to a critical bug identified in SQL Server, the SQLAlchemy "insertmanyvalues" feature which allows fast INSERT of many rows while also supporting RETURNING unfortunately needs to be disabled for SQL Server. SQL Server is apparently unable to guarantee that the order of rows inserted matches the order in which they are sent back by OUTPUT inserted when table-valued rows are used with INSERT in conjunction with OUTPUT inserted. We are trying to see if Microsoft is able to confirm this undocumented behavior however there is no known workaround, other than it's not safe to use table-valued expressions with OUTPUT inserted for now. Fixes: #9603 Change-Id: I4b932fb8774390bbdf4e870a1f6cfe9a78c4b105
Changed the bulk INSERT strategy used for SQL Server "executemany" with pyodbc when ``fast_executemany`` is set to ``True`` by using ``fast_executemany`` / ``cursor.executemany()`` for bulk INSERT that does not include RETURNING, restoring the same behavior as was used in SQLAlchemy 1.4 when this parameter is set. For INSERT statements that use RETURNING, the "insertmanyvalues" strategy continues to be used as it is the only current strategy that supports RETURNING with bulk INSERT. Previously, SQLAlchemy 2.0 would use "insertmanyvalues" for all INSERT statements when ``use_insertmanyvalues`` was left at its default of ``False``, ignoring if ``fast_executemany`` was set. New performance details from end users have shown that ``fast_executemany`` is still much faster for very large datasets as it uses ODBC commands that can receive all rows in a single round trip, allowing for much larger datasizes than the batches that can be sent by the current "insertmanyvalues" strategy. Fixes: #9586 Change-Id: I85955a10ba77c26cdc0c22e362a827d7aaef2852
Fixed issue where string datatypes such as :class:`.CHAR`, :class:`.VARCHAR`, :class:`.TEXT`, as well as binary :class:`.BLOB`, could not be produced with an explicit length of zero, which has special meaning for MySQL. Pull request courtesy J. Nick Koston. Fixes: #9544 Closes: #9543 Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/9543 Pull-request-sha: dc17fc3e93f0ba90881c4efb06016ddf83c7af8b Change-Id: I96925d45f16887f5dfd68a5d4f9284b3abc46d25