Revised the :paramref:`.Connection.execution_options.schema_translate_map`
feature such that the processing of the SQL statement to receive a specific
schema name occurs within the execution phase of the statement, rather than
at the compile phase. This is to support the statement being efficiently
cached. Previously, the current schema being rendered into the statement
for a particular run would be considered as part of the cache key itself,
meaning that for a run against hundreds of schemas, there would be hundreds
of cache keys, rendering the cache much less performant. The new behavior
is that the rendering is done in a similar manner as the "post compile"
rendering added in 1.4 as part of 🎫`4645`, 🎫`4808`.
Fixes: #5004
Change-Id: Ia5c89eb27cc8dc2c5b8e76d6c07c46290a7901b6
The :meth:`.Index.create` and :meth:`.Index.drop` methods now have a
parameter :paramref:`.Index.create.checkfirst`, in the same way as that of
:class:`.Table` and :class:`.Sequence`, which when enabled will cause the
operation to detect if the index exists (or not) before performing a create
or drop operation.
Fixes: #527
Change-Id: Idf994bc016359d0ae86cc64ccb20378115cb66d6
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
Added support for SQL comments on :class:`.Table` and :class:`.Column`
objects, via the new :paramref:`.Table.comment` and
:paramref:`.Column.comment` arguments. The comments are included
as part of DDL on table creation, either inline or via an appropriate
ALTER statement, and are also reflected back within table reflection,
as well as via the :class:`.Inspector`. Supported backends currently
include MySQL, Postgresql, and Oracle.
Co-authored-by: Mike Bayer <mike_mp@zzzcomputing.com>
Fixes: #1546
Change-Id: Ib90683850805a2b4ee198e420dc294f32f15d35d
sort_tables_and_constraints function.
- The DDL generation system of :meth:`.MetaData.create_all`
and :meth:`.Metadata.drop_all` has been enhanced to in most
cases automatically handle the case of mutually dependent
foreign key constraints; the need for the
:paramref:`.ForeignKeyConstraint.use_alter` flag is greatly
reduced. The system also works for constraints which aren't given
a name up front; only in the case of DROP is a name required for
at least one of the constraints involved in the cycle.
fixes#3282
the import structure of many core modules.
``sqlalchemy.schema`` and ``sqlalchemy.types``
remain in the top-level package, but are now just lists of names
that pull from within ``sqlalchemy.sql``. Their implementations
are now broken out among ``sqlalchemy.sql.type_api``, ``sqlalchemy.sql.sqltypes``,
``sqlalchemy.sql.schema`` and ``sqlalchemy.sql.ddl``, the last of which was
moved from ``sqlalchemy.engine``. ``sqlalchemy.sql.expression`` is also
a namespace now which pulls implementations mostly from ``sqlalchemy.sql.elements``,
``sqlalchemy.sql.selectable``, and ``sqlalchemy.sql.dml``.
Most of the "factory" functions
used to create SQL expression objects have been moved to classmethods
or constructors, which are exposed in ``sqlalchemy.sql.expression``
using a programmatic system. Care has been taken such that all the
original import namespaces remain intact and there should be no impact
on any existing applications. The rationale here was to break out these
very large modules into smaller ones, provide more manageable lists
of function names, to greatly reduce "import cycles" and clarify the
up-front importing of names, and to remove the need for redundant
functions and documentation throughout the expression package.