diff options
Diffstat (limited to 'lib/sqlalchemy/sql')
| -rw-r--r-- | lib/sqlalchemy/sql/schema.py | 41 | ||||
| -rw-r--r-- | lib/sqlalchemy/sql/util.py | 2 |
2 files changed, 39 insertions, 4 deletions
diff --git a/lib/sqlalchemy/sql/schema.py b/lib/sqlalchemy/sql/schema.py index 447e102ed..c37b60003 100644 --- a/lib/sqlalchemy/sql/schema.py +++ b/lib/sqlalchemy/sql/schema.py @@ -2271,10 +2271,19 @@ class Column(DialectKWArgs, SchemaItem, ColumnClause[_T]): information is not transferred. """ + fk = [ - ForeignKey(f.column, _constraint=f.constraint) - for f in self.foreign_keys + ForeignKey( + col if col is not None else f._colspec, + _unresolvable=col is None, + _constraint=f.constraint, + ) + for f, col in [ + (fk, fk._resolve_column(raiseerr=False)) + for fk in self.foreign_keys + ] ] + if name is None and self.name is None: raise exc.InvalidRequestError( "Cannot initialize a sub-selectable" @@ -2375,6 +2384,7 @@ class ForeignKey(DialectKWArgs, SchemaItem): link_to_name: bool = False, match: Optional[str] = None, info: Optional[_InfoType] = None, + _unresolvable: bool = False, **dialect_kw: Any, ): r""" @@ -2448,6 +2458,7 @@ class ForeignKey(DialectKWArgs, SchemaItem): """ self._colspec = coercions.expect(roles.DDLReferredColumnRole, column) + self._unresolvable = _unresolvable if isinstance(self._colspec, str): self._table_column = None @@ -2658,6 +2669,11 @@ class ForeignKey(DialectKWArgs, SchemaItem): parenttable = self.parent.table + if self._unresolvable: + schema, tname, colname = self._column_tokens + tablekey = _get_table_key(tname, schema) + return parenttable, tablekey, colname + # assertion # basically Column._make_proxy() sends the actual # target Column to the ForeignKey object, so the @@ -2742,13 +2758,30 @@ class ForeignKey(DialectKWArgs, SchemaItem): """ + return self._resolve_column() + + @overload + def _resolve_column(self, *, raiseerr: Literal[True] = ...) -> Column[Any]: + ... + + @overload + def _resolve_column( + self, *, raiseerr: bool = ... + ) -> Optional[Column[Any]]: + ... + + def _resolve_column( + self, *, raiseerr: bool = True + ) -> Optional[Column[Any]]: _column: Column[Any] if isinstance(self._colspec, str): parenttable, tablekey, colname = self._resolve_col_tokens() - if tablekey not in parenttable.metadata: + if self._unresolvable or tablekey not in parenttable.metadata: + if not raiseerr: + return None raise exc.NoReferencedTableError( "Foreign key associated with column '%s' could not find " "table '%s' with which to generate a " @@ -2757,6 +2790,8 @@ class ForeignKey(DialectKWArgs, SchemaItem): tablekey, ) elif parenttable.key not in parenttable.metadata: + if not raiseerr: + return None raise exc.InvalidRequestError( "Table %s is no longer associated with its " "parent MetaData" % parenttable diff --git a/lib/sqlalchemy/sql/util.py b/lib/sqlalchemy/sql/util.py index 390e23952..0400ab3fe 100644 --- a/lib/sqlalchemy/sql/util.py +++ b/lib/sqlalchemy/sql/util.py @@ -235,7 +235,7 @@ def find_left_clause_to_join_from( if set(f.c).union(s.c).issuperset(cols_in_onclause): idx.append(i) break - elif Join._can_join(f, s) or onclause is not None: + elif onclause is not None or Join._can_join(f, s): idx.append(i) break |