Fixed bug in SQL Server dialect with new "max_identifier_length" feature
where the mssql dialect already featured this flag, and the implementation
did not accommodate for the new initialization hook correctly.
Fixes: #4857
Change-Id: I96a9c6ca9549d8f6fb167c0333f684e8d922a3bf
(cherry picked from commit 2ba70aba90)
Added new :func:`.create_engine` parameter
:paramref:`.create_engine.max_identifier_length`. This overrides the
dialect-coded "max identifier length" in order to accommodate for databases
that have recently changed this length and the SQLAlchemy dialect has
not yet been adjusted to detect for that version. This parameter interacts
with the existing :paramref:`.create_engine.label_length` parameter in that
it establishes the maximum (and default) value for anonymously generated
labels.
The Oracle dialect now emits a warning if Oracle version 12.2 or greater is
used, and the :paramref:`.create_engine.max_identifier_length` parameter is
not set. The version in this specific case defaults to that of the
"compatibility" version set in the Oracle server configuration, not the
actual server version. In version 1.4, the default max_identifier_length
for 12.2 or greater will move to 128 characters. In order to maintain
forwards compatibility, applications should set
:paramref:`.create_engine.max_identifier_length` to 30 in order to maintain
the same length behavior, or to 128 in order to test the upcoming behavior.
This length determines among other things how generated constraint names
are truncated for statements like ``CREATE CONSTRAINT`` and ``DROP
CONSTRAINT``, which means a the new length may produce a name-mismatch
against a name that was generated with the old length, impacting database
migrations.
Fixes: #4857
Change-Id: Ib62efb00c6180c375869029b57353d90385d7950
(cherry picked from commit 88761b8b0b0cfa67cdd6a4913e3a0ea5cba93cbb)
Applied on top of a pure run of black -l 79 in
I7eda77fed3d8e73df84b3651fd6cfcfe858d4dc9, this set of changes
resolves all remaining flake8 conditions for those codes
we have enabled in setup.cfg.
Included are resolutions for all remaining flake8 issues
including shadowed builtins, long lines, import order, unused
imports, duplicate imports, and docstring issues.
Change-Id: I4f72d3ba1380dd601610ff80b8fb06a2aff8b0fe
This is a straight reformat run using black as is, with no edits
applied at all.
The black run will format code consistently, however in
some cases that are prevalent in SQLAlchemy code it produces
too-long lines. The too-long lines will be resolved in the
following commit that will resolve all remaining flake8 issues
including shadowed builtins, long lines, import order, unused
imports, duplicate imports, and docstring issues.
Change-Id: I7eda77fed3d8e73df84b3651fd6cfcfe858d4dc9
a label that overlapped another label that is not truncated; this
because the length threshhold for truncation was greater than
the portion of the label that remains after truncation. These
two values have now been made the same; label_length - 6.
The effect here is that shorter column labels will be "truncated"
where they would not have been truncated before.
fixes#3396
become an externally usable package but still remains within the main sqlalchemy parent package.
in this system, we use kind of an ugly hack to get the noseplugin imported outside of the
"sqlalchemy" package, while still making it available within sqlalchemy for usage by
third party libraries.
is applied to columns in SELECT statements
allows "truncated" labels, that is label names
that are generated in Python which exceed
the maximum identifier length (note this is
configurable via label_length on create_engine()),
to be properly referenced when rendered inside
of a subquery, as well as to be present
in a result set row using their original
in-Python names. [ticket:2396]
- apply pep8 to test_labels
Mike Bayer