Fixed #16055 -- Fixed crash when filtering against char/text GenericRelation relation on PostgreSQL.

3 files changed, 21 insertions, 0 deletions

diff --git a/django/db/backends/base/operations.py b/django/db/backends/base/operations.py
index d2bc336dd8..6f10e31cd5 100644
--- a/django/db/backends/base/operations.py
+++ b/django/db/backends/base/operations.py
@@ -8,6 +8,7 @@ import sqlparse
 from django.conf import settings
 from django.db import NotSupportedError, transaction
 from django.db.backends import utils
+from django.db.models.expressions import Col
 from django.utils import timezone
 from django.utils.encoding import force_str
 
@@ -776,3 +777,9 @@ class BaseDatabaseOperations:
 
     def on_conflict_suffix_sql(self, fields, on_conflict, update_fields, unique_fields):
         return ""
+
+    def prepare_join_on_clause(self, lhs_table, lhs_field, rhs_table, rhs_field):
+        lhs_expr = Col(lhs_table, lhs_field)
+        rhs_expr = Col(rhs_table, rhs_field)
+
+        return lhs_expr, rhs_expr
diff --git a/django/db/backends/oracle/features.py b/django/db/backends/oracle/features.py
index 3d77a615c8..05dc552a98 100644
--- a/django/db/backends/oracle/features.py
+++ b/django/db/backends/oracle/features.py
@@ -120,6 +120,9 @@ class DatabaseFeatures(BaseDatabaseFeatures):
             "migrations.test_operations.OperationTests."
             "test_alter_field_pk_fk_db_collation",
         },
+        "Oracle doesn't support comparing NCLOB to NUMBER.": {
+            "generic_relations_regress.tests.GenericRelationTests.test_textlink_filter",
+        },
     }
     django_test_expected_failures = {
         # A bug in Django/cx_Oracle with respect to string handling (#23843).
diff --git a/django/db/backends/postgresql/operations.py b/django/db/backends/postgresql/operations.py
index 18cfcb29cb..aa839f5634 100644
--- a/django/db/backends/postgresql/operations.py
+++ b/django/db/backends/postgresql/operations.py
@@ -12,6 +12,7 @@ from django.db.backends.postgresql.psycopg_any import (
 )
 from django.db.backends.utils import split_tzname_delta
 from django.db.models.constants import OnConflict
+from django.db.models.functions import Cast
 from django.utils.regex_helper import _lazy_re_compile
 
 
@@ -413,3 +414,13 @@ class DatabaseOperations(BaseDatabaseOperations):
             update_fields,
             unique_fields,
         )
+
+    def prepare_join_on_clause(self, lhs_table, lhs_field, rhs_table, rhs_field):
+        lhs_expr, rhs_expr = super().prepare_join_on_clause(
+            lhs_table, lhs_field, rhs_table, rhs_field
+        )
+
+        if lhs_field.db_type(self.connection) != rhs_field.db_type(self.connection):
+            rhs_expr = Cast(rhs_expr, lhs_field)
+
+        return lhs_expr, rhs_expr