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]}.
Aggregation over subquery produced syntactically incorrect queries in
some cases as Django didn't ensure that source expressions of the
aggregation were present in the subquery.
The .dates() queries were implemented by using custom Query, QuerySet,
and Compiler classes. Instead implement them by using expressions and
database converters APIs.
Added relabeled_clone() method to sql.Query to fix the problem. It
manifested itself in rare cases where at least double nested subquery's
filter condition might target non-existing alias.
Thanks to Trac alias ris for reporting the problem.
Complete rework of translating data values from database
Deprecation of SubfieldBase, removal of resolve_columns and
convert_values in favour of a more general converter based approach and
public API Field.from_db_value(). Now works seamlessly with aggregation,
.values() and raw queries.
Thanks to akaariai in particular for extensive advice and inspiration,
also to shaib, manfre and timograham for their reviews.
A regression caused queries to produce incorrect results for cases where
extra(select) is excluded by values() but included by extra(order_by)
The regression was caused by 2f35c6f10f.
Tim Graham
Anssi Kääriäinen
Anssi Kääriäinen
Claude Paroz
Loic Bistuer
Josh Smeaton
Simon Charette
Michał Modzelewski
Daniel Pyrathon
Piotr Pawlaczek
Niclas Olofsson
Michael Hall
Jon Dufresne
Carl Meyer
Collin Anderson
Thomas Chaumeny
Gabe Jackson
Thomas Chaumeny
Matt Robenolt
Marc Tamlyn
Andrew Torpedov
Anubhav Joshi
Rajiv Makhijani