🎫`3184` would cause index operations to fail on Postgresql
versions 8.4 and earlier. The enhancements are now
disabled when using an older version of Postgresql.
fixes#3343
DROP TYPE instruction when a plain ``table.drop()`` is called,
assuming the object is not associated directly with a
:class:`.MetaData` object. In order to accomodate the use case of
an enumerated type shared between multiple tables, the type should
be associated directly with the :class:`.MetaData` object; in this
case the type will only be created at the metadata level, or if
created directly. The rules for create/drop of
Postgresql enumerated types have been highly reworked in general.
fixes#3319
return type is not strictly assumed to be boolean; it now
returns a :class:`.Boolean` subclass called :class:`.MatchType`.
The type will still produce boolean behavior when used in Python
expressions, however the dialect can override its behavior at
result time. In the case of MySQL, while the MATCH operator
is typically used in a boolean context within an expression,
if one actually queries for the value of a match expression, a
floating point value is returned; this value is not compatible
with SQLAlchemy's C-based boolean processor, so MySQL's result-set
behavior now follows that of the :class:`.Float` type.
A new operator object ``notmatch_op`` is also added to better allow
dialects to define the negation of a match operation.
fixes#3263
``pg_catalog.pg_table_is_visible(c.oid)``, rather than testing
for an exact schema match, when the schema name is None; this
so that the method will also illustrate that temporary tables
are present. Note that this is a behavioral change, as Postgresql
allows a non-temporary table to silently overwrite an existing
temporary table of the same name, so this changes the behavior
of ``checkfirst`` in that unusual scenario.
fixes#3264
- add a test for PG reflection of unique index without any unique
constraint
- for PG, don't include 'duplicates_constraint' in the entry
if the index does not actually mirror a constraint
- use a distinct method for unique constraint reflection within table
- catch unique constraint not implemented condition; this may
be within some dialects and also is expected to be supported by
Alembic tests
- migration + changelogs for #3184
- add individual doc notes as well to MySQL, Postgreql
fixes#3184
Calls to reflect a table did not create any UniqueConstraint objects.
The reflection core made no calls to get_unique_constraints and as
a result, the sqlite dialect would never reflect any unique constraints.
MySQL transparently converts unique constraints into unique indexes, but
SQLAlchemy would reflect those as an Index object and as a
UniqueConstraint. The reflection core will now deduplicate the unique
constraints.
PostgreSQL would reflect unique constraints as an Index object and as
a UniqueConstraint object. The reflection core will now deduplicate
the unique indexes.
constructs are now importable from the "from sqlalchemy" namespace,
just like every other Core construct.
- The implicit conversion of strings to :func:`.text` constructs
when passed to most builder methods of :func:`.select` as
well as :class:`.Query` now emits a warning with just the
plain string sent. The textual conversion still proceeds normally,
however. The only method that accepts a string without a warning
are the "label reference" methods like order_by(), group_by();
these functions will now at compile time attempt to resolve a single
string argument to a column or label expression present in the
selectable; if none is located, the expression still renders, but
you get the warning again. The rationale here is that the implicit
conversion from string to text is more unexpected than not these days,
and it is better that the user send more direction to the Core / ORM
when passing a raw string as to what direction should be taken.
Core/ORM tutorials have been updated to go more in depth as to how text
is handled.
fixes#2992
- return a list of dicts like other methods do
- don't combine 'schema' with 'name', leave them separate
- support '*' argument so that we can retrieve cross-schema
if needed
- remove "conn" argument
- use bound parameters for 'schema' in SQL
- order by schema, name, label
- adapt _load_enums changes to column reflection
- changelog
- module docs for get_enums()
- add drop of enums to --dropfirst
otherwise render a SQL NULL column value, rather than a JSON-encoded
``'null'``. To support this case, changes are as follows:
* The value :func:`.null` can now be specified, which will always
result in a NULL value resulting in the statement.
* A new parameter :paramref:`.JSON.none_as_null` is added, which
when True indicates that the Python ``None`` value should be
peristed as SQL NULL, rather than JSON-encoded ``'null'``.
Retrival of NULL as None is also repaired for DBAPIs other than
psycopg2, namely pg8000.
fixes#3159
non-standard DBAPI exceptions, such as the psycopg2
TransactionRollbackError. These exceptions will now be raised
using the closest available subclass in ``sqlalchemy.exc``, in the
case of TransactionRollbackError, ``sqlalchemy.exc.OperationalError``.
fixes#3075
While "oid" is generally a private type within PG that is not exposed
in modern versions, there are some PG use cases such as large object
support where these types might be exposed, as well as within some
user-reported schema reflection use cases.
fixes#3002
is needed to allow the ORM to skip over trying to "hash" an ORM-mapped
HSTORE column when requesting it in a mixed column/entity list.
Patch courtesy Gunnlaugur Þór Briem. Fixes#3053
As with postgresql+psycopg2,
execution_options(isolation_level='AUTOCOMMIT') now works for the
postgresql+pg8000 dialect.
Also enabled the autocommit test in test_dialect.py for pg8000.
the ARRAY type when using psycopg2. The psycopg2 dialect now
employs use of the psycopg2.extras.register_uuid() hook
so that UUID values are always passed to/from the DBAPI as
UUID() objects. The :paramref:`.UUID.as_uuid` flag is still
honored, except with psycopg2 we need to convert returned
UUID objects back into strings when this is disabled.
fixes#2940
Mike Bayer