When an error occurred during the cursor.execute statement, the cursor
is closed. This operation did not fail with client-side cursors. Now,
with server-side cursors, the close operation might fail (example
below). The original error should be raised, not the one raised by
cursor.close(), this is only clean-up code.
For example, one can attempt to create a named cursor for an invalid
query. psycopg will raise an error about the invalid query and the
server-side cursor will not be created on PostgreSQL. When the code
attempts to cursor.close(), it asks psycopg to close a cursor that was
not created. pyscopg raises a new error: psycopg2.OperationalError:
cursor "_django_curs_140365867840512_20" does not exist.
Thanks to Josh Smeaton for the idea of implementing server-side cursors
in PostgreSQL from the iterator method, and Anssi Kääriäinen and Kevin
Turner for their previous work. Also Simon Charette and Tim Graham for
review.
The removed test was added in the original select_related() validation
patch (45d4e43d2d), but there doesn't
seem to be any reason for it.
Thanks Claude Paroz for help and review.
When the query's model had a self-referential foreign key, the
compiler.get_group_by() code incorrectly used the self-referential
foreign key's column (for example parent_id) as GROUP BY clause
when it should have used the model's primary key column (id).
Fixed queries where an expression was used in order_by() but the
expression wasn't in the query's select clause (for example the
expression could be masked by .values() call)
Thanks to Trac alias MattBlack85 for the report.
Field.rel is now deprecated. Rel objects have now also remote_field
attribute. This means that self == self.remote_field.remote_field.
In addition, made the Rel objects a bit more like Field objects. Still,
marked ManyToManyFields as null=True.
As suggested by Anssi. This has the slightly strange side effect of
passing the expression to Expression.convert_value has the expression
passed back to it, but it allows more complex patterns of expressions.
Instead of splitting filter clauses to where and having parts before
adding them to query.where or query.having, add all filter clauses to
query.where, and when compiling the query split the where to having and
where parts.
Refactored compiler SELECT, GROUP BY and ORDER BY generation.
While there, also refactored select_related() implementation
(get_cached_row() and get_klass_info() are now gone!).
Made get_db_converters() method work on expressions instead of
internal_type. This allows the backend converters to target
specific expressions if need be.
Added query.context, this can be used to set per-query state.
Also changed the signature of database converters. They now accept
context as an argument.
Also removed Query.join_map. This structure was used to speed up join
reuse calculation. Initial benchmarking shows that this isn't actually
needed. If there are use cases where the removal has real-world
performance implications, it should be relatively straightforward to
reintroduce it as map {alias: [Join-like objects]}.
Florian Apolloner
François Freitag
Florian Apolloner
Daniel Hillier
Tim Graham
François Freitag
Mikhail Denisenko
Simon Charette
Johannes Dollinger
acrefoot
Anssi Kääriäinen
Sergey Fedoseev
Dmitry Dygalo
Alex Hill
Valentina Mukhamedzhanova
risicle
Anssi Kääriäinen
Jay Wineinger
Marc Tamlyn
Claude Paroz
Josh Smeaton
Michał Modzelewski
Daniel Pyrathon
Niclas Olofsson