Fixed #31630 -- Replaced introspection features with DatabaseFeatures.introspected_field_types.

django/db/backends/base/features.py

@@ -128,38 +128,22 @@ class BaseDatabaseFeatures:
     # Can the backend introspect an AutoField, instead of an IntegerField?
     can_introspect_autofield = False
 
-    # Can the backend introspect a BigIntegerField, instead of an IntegerField?
-    can_introspect_big_integer_field = True
-
-    # Can the backend introspect an BinaryField, instead of an TextField?
-    can_introspect_binary_field = True
-
-    # Can the backend introspect an DecimalField, instead of an FloatField?
-    can_introspect_decimal_field = True
-
-    # Can the backend introspect a DurationField, instead of a BigIntegerField?
-    can_introspect_duration_field = True
-
-    # Can the backend introspect an IPAddressField, instead of an CharField?
-    can_introspect_ip_address_field = False
-
-    # Can the backend introspect a PositiveIntegerField, instead of an IntegerField?
-    can_introspect_positive_integer_field = False
-
-    # Can the backend introspect a SmallIntegerField, instead of an IntegerField?
-    can_introspect_small_integer_field = False
-
-    # Can the backend introspect a TimeField, instead of a DateTimeField?
-    can_introspect_time_field = True
-
-    # Some backends may not be able to differentiate BigAutoField or
-    # SmallAutoField from other fields such as AutoField.
-    introspected_big_auto_field_type = 'BigAutoField'
-    introspected_small_auto_field_type = 'SmallAutoField'
-
-    # Some backends may not be able to differentiate BooleanField from other
-    # fields such as IntegerField.
-    introspected_boolean_field_type = 'BooleanField'
+    # Map fields which some backends may not be able to differentiate to the
+    # field it's introspected as.
+    introspected_field_types = {
+        'BigAutoField': 'BigAutoField',
+        'BigIntegerField': 'BigIntegerField',
+        'BinaryField': 'BinaryField',
+        'BooleanField': 'BooleanField',
+        'DurationField': 'DurationField',
+        'GenericIPAddressField': 'GenericIPAddressField',
+        'PositiveBigIntegerField': 'PositiveBigIntegerField',
+        'PositiveIntegerField': 'PositiveIntegerField',
+        'PositiveSmallIntegerField': 'PositiveSmallIntegerField',
+        'SmallAutoField': 'SmallAutoField',
+        'SmallIntegerField': 'SmallIntegerField',
+        'TimeField': 'TimeField',
+    }
 
     # Can the backend introspect the column order (ASC/DESC) for indexes?
     supports_index_column_ordering = True

django/db/backends/mysql/features.py

@@ -15,11 +15,6 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     supports_regex_backreferencing = False
     supports_date_lookup_using_string = False
     can_introspect_autofield = True
-    can_introspect_binary_field = False
-    can_introspect_duration_field = False
-    can_introspect_small_integer_field = True
-    can_introspect_positive_integer_field = True
-    introspected_boolean_field_type = 'IntegerField'
     supports_index_column_ordering = False
     supports_timezones = False
     requires_explicit_null_ordering_when_grouping = True
@@ -70,6 +65,16 @@ class DatabaseFeatures(BaseDatabaseFeatures):
         "Confirm support for introspected foreign keys"
         return self._mysql_storage_engine != 'MyISAM'
 
+    @cached_property
+    def introspected_field_types(self):
+        return {
+            **super().introspected_field_types,
+            'BinaryField': 'TextField',
+            'BooleanField': 'IntegerField',
+            'DurationField': 'BigIntegerField',
+            'GenericIPAddressField': 'CharField',
+        }
+
     @cached_property
     def can_return_columns_from_insert(self):
         return self.connection.mysql_is_mariadb and self.connection.mysql_version >= (10, 5, 0)

django/db/backends/oracle/features.py

@@ -1,5 +1,6 @@
 from django.db import InterfaceError
 from django.db.backends.base.features import BaseDatabaseFeatures
+from django.utils.functional import cached_property
 
 
 class DatabaseFeatures(BaseDatabaseFeatures):
@@ -22,7 +23,6 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     supports_tablespaces = True
     supports_sequence_reset = False
     can_introspect_materialized_views = True
-    can_introspect_time_field = False
     atomic_transactions = False
     supports_combined_alters = False
     nulls_order_largest = True
@@ -61,3 +61,15 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     allows_multiple_constraints_on_same_fields = False
     supports_boolean_expr_in_select_clause = False
     supports_primitives_in_json_field = False
+
+    @cached_property
+    def introspected_field_types(self):
+        return {
+            **super().introspected_field_types,
+            'GenericIPAddressField': 'CharField',
+            'PositiveBigIntegerField': 'BigIntegerField',
+            'PositiveIntegerField': 'IntegerField',
+            'PositiveSmallIntegerField': 'IntegerField',
+            'SmallIntegerField': 'IntegerField',
+            'TimeField': 'DateTimeField',
+        }

django/db/backends/postgresql/features.py

@@ -22,10 +22,7 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     can_release_savepoints = True
     supports_tablespaces = True
     supports_transactions = True
-    can_introspect_autofield = True
-    can_introspect_ip_address_field = True
     can_introspect_materialized_views = True
-    can_introspect_small_integer_field = True
     can_distinct_on_fields = True
     can_rollback_ddl = True
     supports_combined_alters = True
@@ -61,6 +58,15 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     supports_deferrable_unique_constraints = True
     has_json_operators = True
 
+    @cached_property
+    def introspected_field_types(self):
+        return {
+            **super().introspected_field_types,
+            'PositiveBigIntegerField': 'BigIntegerField',
+            'PositiveIntegerField': 'IntegerField',
+            'PositiveSmallIntegerField': 'SmallIntegerField',
+        }
+
     @cached_property
     def is_postgresql_10(self):
         return self.connection.pg_version >= 100000

django/db/backends/sqlite3/features.py

@@ -19,12 +19,6 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     max_query_params = 999
     supports_mixed_date_datetime_comparisons = False
     can_introspect_autofield = True
-    can_introspect_decimal_field = False
-    can_introspect_duration_field = False
-    can_introspect_positive_integer_field = True
-    can_introspect_small_integer_field = True
-    introspected_big_auto_field_type = 'AutoField'
-    introspected_small_auto_field_type = 'AutoField'
     supports_transactions = True
     atomic_transactions = False
     can_rollback_ddl = True
@@ -51,6 +45,16 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     supports_order_by_nulls_modifier = Database.sqlite_version_info >= (3, 30, 0)
     order_by_nulls_first = True
 
+    @cached_property
+    def introspected_field_types(self):
+        return{
+            **super().introspected_field_types,
+            'BigAutoField': 'AutoField',
+            'DurationField': 'BigIntegerField',
+            'GenericIPAddressField': 'CharField',
+            'SmallAutoField': 'AutoField',
+        }
+
     @cached_property
     def supports_json_field(self):
         try: