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author | Simon Charette <charette.s@gmail.com> | 2022-09-15 13:27:32 -0400 |
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committer | GitHub <noreply@github.com> | 2022-09-15 19:27:32 +0200 |
commit | 3ba7f2e9069c54db6d6d9d2fd1945b2dbc935d9c (patch) | |
tree | a3d0c4e184c63f288f22a207d302515650b10aa0 /django/db/models/sql/compiler.py | |
parent | a69b0e9cfe0af7cd2deaf55c069453c4c4598604 (diff) | |
download | django-3ba7f2e9069c54db6d6d9d2fd1945b2dbc935d9c.tar.gz |
Refs #28333 -- Explicitly ordered outer qualify query on window filtering.
While most backends will propagate derived table ordering as long as
the outer query doesn't perform additional processing the SQL specs
doesn't explicitly state the ordering must be maintained.
Diffstat (limited to 'django/db/models/sql/compiler.py')
-rw-r--r-- | django/db/models/sql/compiler.py | 56 |
1 files changed, 42 insertions, 14 deletions
diff --git a/django/db/models/sql/compiler.py b/django/db/models/sql/compiler.py index 27310e5d9f..c7efa469a8 100644 --- a/django/db/models/sql/compiler.py +++ b/django/db/models/sql/compiler.py @@ -607,24 +607,41 @@ class SQLCompiler: select = { expr: alias for expr, _, alias in self.get_select(with_col_aliases=True)[0] } + select_aliases = set(select.values()) qual_aliases = set() replacements = {} - expressions = list(self.qualify.leaves()) - while expressions: - expr = expressions.pop() - if select_alias := (select.get(expr) or replacements.get(expr)): - replacements[expr] = select_alias - elif isinstance(expr, Lookup): - expressions.extend(expr.get_source_expressions()) - else: - num_qual_alias = len(qual_aliases) - select_alias = f"qual{num_qual_alias}" - qual_aliases.add(select_alias) - inner_query.add_annotation(expr, select_alias) - replacements[expr] = select_alias + + def collect_replacements(expressions): + while expressions: + expr = expressions.pop() + if expr in replacements: + continue + elif select_alias := select.get(expr): + replacements[expr] = select_alias + elif isinstance(expr, Lookup): + expressions.extend(expr.get_source_expressions()) + elif isinstance(expr, Ref): + if expr.refs not in select_aliases: + expressions.extend(expr.get_source_expressions()) + else: + num_qual_alias = len(qual_aliases) + select_alias = f"qual{num_qual_alias}" + qual_aliases.add(select_alias) + inner_query.add_annotation(expr, select_alias) + replacements[expr] = select_alias + + collect_replacements(list(self.qualify.leaves())) self.qualify = self.qualify.replace_expressions( {expr: Ref(alias, expr) for expr, alias in replacements.items()} ) + order_by = [] + for order_by_expr, *_ in self.get_order_by(): + collect_replacements(order_by_expr.get_source_expressions()) + order_by.append( + order_by_expr.replace_expressions( + {expr: Ref(alias, expr) for expr, alias in replacements.items()} + ) + ) inner_query_compiler = inner_query.get_compiler( self.using, elide_empty=self.elide_empty ) @@ -657,7 +674,18 @@ class SQLCompiler: ")", self.connection.ops.quote_name("qualify_mask"), ] - return result, list(inner_params) + qualify_params + params = list(inner_params) + qualify_params + # As the SQL spec is unclear on whether or not derived tables + # ordering must propagate it has to be explicitly repeated on the + # outer-most query to ensure it's preserved. + if order_by: + ordering_sqls = [] + for ordering in order_by: + ordering_sql, ordering_params = self.compile(ordering) + ordering_sqls.append(ordering_sql) + params.extend(ordering_params) + result.extend(["ORDER BY", ", ".join(ordering_sqls)]) + return result, params def as_sql(self, with_limits=True, with_col_aliases=False): """ |