of :class:`.ForeignKeyConstraint` is silently ignored on the MySQL
backend, will be reverted as of 0.9; this keyword will now render again, raising
errors on MySQL as it is not understood - the same behavior will also
apply to the ``initially`` keyword. In 0.8, the keywords will remain
ignored but a warning is emitted. Additionally, the ``match`` keyword
now raises a :class:`.CompileError` on 0.9 and emits a warning on 0.8;
this keyword is not only silently ignored by MySQL but also breaks
the ON UPDATE/ON DELETE options.
To use a :class:`.ForeignKeyConstraint`
that does not render or renders differently on MySQL, use a custom
compilation option. An example of this usage has been added to the
documentation, see :ref:`mysql_foreign_keys`.
[ticket:2721] [ticket:2839]
behavior as that of :class:`.mysql.ENUM`. Quotes are not required when
setting up the value, but quotes that are present will be auto-detected
along with a warning. This also helps with Alembic where
the SET type doesn't render with quotes. [ticket:2817]
mssql to ensure that any literal SQL expression values are
rendered directly as literals, instead of as bound parameters,
within a CREATE INDEX statement. [ticket:2742]
- don't need expression_as_ddl(); literal_binds and include_table
take care of this functionality.
instead of relying upon various ``quote=True`` flags being passed around,
these flags are converted into rich string objects with quoting information
included at the point at which they are passed to common schema constructs
like :class:`.Table`, :class:`.Column`, etc. This solves the issue
of various methods that don't correctly honor the "quote" flag such
as :meth:`.Engine.has_table` and related methods. The :class:`.quoted_name`
object is a string subclass that can also be used explicitly if needed;
the object will hold onto the quoting preferences passed and will
also bypass the "name normalization" performed by dialects that
standardize on uppercase symbols, such as Oracle, Firebird and DB2.
The upshot is that the "uppercase" backends can now work with force-quoted
names, such as lowercase-quoted names and new reserved words.
[ticket:2812]
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.
regexp apparently were not fully implemented correctly; while the
arguments were accepted, in practice they would have no effect;
this has been fixed. Also in 0.8.3.
[ticket:2781]
This controls the value of the ``retaining`` flag sent to the
``commit()`` and ``rollback()`` methods of the DBAPI connection.
Defaults to False. Also in 0.8.2, where it defaults to True.
[ticket:2763]
Postgresql dialect to no longer inject a hardcoded ``::timestamp``
or similar cast into the given expression, as this interfered
with types such as timezone-aware datetimes, but also
does not appear to be at all necessary with modern versions
of psycopg2. Also in 0.8.2.
[ticket:2740]
INT64 has been fixed so that LONG is treated as INTEGER,
INT64 treated as BIGINT, unless the type has a "precision"
in which case it's treated as NUMERIC. Patch courtesy
Russell Stuart.
[ticket:2757]
backslashed quotes would not be escaped correctly when
using the "non native" (i.e. non-psycopg2) means
of translating HSTORE data. Patch courtesy Ryan Kelly.
[ticket:2766]
- add support for correlations to propagate all the way in; because
correlations require context now, need to make sure a select enclosure
of any level takes effect any number of levels deep.
- fix what we said correlate_except() was supposed to do when we first
released #2668 - "the FROM clause is left intact if the correlated SELECT
is not used in the context of an enclosing SELECT..." - it was not
considering the "existing_froms" collection at all, and prohibited
additional FROMs from being placed in an any() or has().
- add test for multilevel any()
- lots of docs, including glossary entries as we really need to define
"WHERE clause", "columns clause" etc. so that we can explain correlation better
- based on the insight that a SELECT can correlate anything that ultimately
came from an enclosing SELECT that links to this one via WHERE/columns/HAVING/ORDER BY,
have the compiler keep track of the FROM lists that correspond in this way,
link it to the asfrom flag, so that we send to _get_display_froms() the exact
list of candidate FROMs to correlate. no longer need any asfrom logic in the
Select() itself
- preserve 0.8.1's behavior for correlation when no correlate options are given, not
to mention 0.7 and prior's behavior of not propagating implicit correlation more than one level..
this is to reduce surprises/hard-to-debug situations when a user isn't trying
to correlate anything.
If SQLite keywords are used as column names, they are
quoted. The code parsing the information about table
unique constraints should be modified so that it properly
removes double-quotes from column names.
One can use this to emit statements, which can not be
executed within a transaction (e. g. CREATE DATABASE):
from sqlalchemy import create_engine
eng = create_engine('postgresql://test:test@localhost/test')
conn = eng.connect().execution_options(isolation_level='AUTOCOMMIT')
conn.execute('CREATE DATABASE test2;')
Fixes issue #2072.
Inspection API already supports reflection of table
indexes information and those also include unique
constraints (at least for PostgreSQL and MySQL).
But it could be actually useful to distinguish between
indexes and plain unique constraints (though both are
implemented in the same way internally in RDBMS).
This change adds a new method to Inspection API - get_unique_constraints()
and implements it for SQLite, PostgreSQL and MySQL dialects.
Currently, one can specify the prefix length for an index
column using 'mysql_length' keyword argument when creating
an Index instance. But in case of composite indexes the
prefix length value is applied only to the last column.
Extend the existing API in way so that 'mysql_length' argument
value can be either:
- an integer specifying the same prefix length value
for each column of an index
- a (column_name --> integer value) mapping specifying
the prefix length value for each column of an index
separately
Fixes issue #2704.
Mike Bayer