Schema Diff: ignore defseqrelid to avoid false SERIAL/BIGSERIAL diffs and invalid ALTER SQL (#10236)

web/pgadmin/browser/server_groups/servers/databases/schemas/tables/schema_diff_table_utils.py

@@ -24,8 +24,19 @@ class SchemaDiffTableCompare(SchemaDiffObjectCompare):
                             'rows_cnt', 'hastoasttable', 'relhassubclass',
                             'relacl_str', 'setting']
 
+    # 'seqrelid' (the sequence a column owns) and 'defseqrelid' (the
+    # sequence referenced by the column's nextval() DEFAULT) are compared
+    # against EACH OTHER by get_formatted_columns() to reproject a column
+    # as SERIAL/BIGSERIAL/SMALLSERIAL (see columns/utils.py, #9896/#10100/
+    # #10101) -- but the resulting raw sequence OIDs are otherwise
+    # meaningless across two independently-created databases, even when
+    # both sides have an identical SERIAL column. Without ignoring
+    # 'defseqrelid' here too, Schema Diff falsely reports such columns (and
+    # therefore their whole table) as different, and generates an invalid
+    # `ALTER COLUMN ... TYPE bigserial` statement despite both sides having
+    # the exact same reprojected cltype.
     column_keys_to_ignore = ['atttypid', 'edit_types', 'elemoid', 'seqrelid',
-                             'indkey', 'seqtypid']
+                             'indkey', 'seqtypid', 'defseqrelid']
 
     constraint_keys_to_ignore = ['relname', 'nspname', 'parent_tbl',
                                  'attrelid', 'adrelid', 'fknsp', 'confrelid',

web/pgadmin/browser/server_groups/servers/databases/schemas/tables/tests/test_schema_diff_serial_column_ignore.py

@@ -0,0 +1,83 @@
+##########################################################################
+#
+# pgAdmin 4 - PostgreSQL Tools
+#
+# Copyright (C) 2013 - 2026, The pgAdmin Development Team
+# This software is released under the PostgreSQL Licence
+#
+##########################################################################
+
+"""Unit tests for SchemaDiffTableCompare's column comparison, verifying
+that a SERIAL/BIGSERIAL column's raw sequence OID ('defseqrelid') does not
+cause Schema Diff to report a false-positive difference (#10236).
+"""
+
+from pgadmin.browser.server_groups.servers.databases.schemas.tables.\
+    schema_diff_table_utils import SchemaDiffTableCompare
+from pgadmin.utils.route import BaseTestGenerator
+
+
+def _make_bigserial_column(defseqrelid, **overrides):
+    """A column dict as returned by get_formatted_columns() for a
+    genuine, already-reprojected BIGSERIAL column."""
+    defaults = dict(
+        name='adl_id', cltype='bigserial', typname='bigserial',
+        atttypid=20, attlen=8, attnum=1, elemoid=20, seqtypid=20,
+        indkey=None, seqrelid=defseqrelid, defseqrelid=defseqrelid,
+        defval='', attnotnull=True, attacl=[],
+    )
+    defaults.update(overrides)
+    return defaults
+
+
+class TestSchemaDiffSerialColumnIgnore(BaseTestGenerator):
+    """Unit tests for SchemaDiffTableCompare.compare_target_cols()."""
+
+    scenarios = [
+        ('Identical BIGSERIAL columns with differing sequence OIDs are '
+         'not flagged as different',
+         dict(test_method='test_differing_defseqrelid_not_flagged')),
+        ('A genuinely different column is still flagged as different',
+         dict(test_method='test_genuine_difference_still_flagged')),
+    ]
+
+    def runTest(self):
+        getattr(self, self.test_method)()
+
+    def test_differing_defseqrelid_not_flagged(self):
+        # Two independently-created databases will assign different raw
+        # OIDs to each table's owned sequence, even for structurally
+        # identical BIGSERIAL columns. That OID difference alone must not
+        # cause the column (and thus the table) to be reported as
+        # different, and must not trigger an invalid
+        # `ALTER COLUMN ... TYPE bigserial` in the generated diff SQL.
+        source = _make_bigserial_column(defseqrelid=16482)
+        target_cols = [_make_bigserial_column(defseqrelid=98213)]
+
+        added = []
+        updated = []
+        SchemaDiffTableCompare.compare_target_cols(
+            source, target_cols, added, updated)
+
+        self.assertEqual(added, [])
+        self.assertEqual(updated, [])
+        # The matching target column must have been consumed.
+        self.assertEqual(target_cols, [])
+
+    def test_genuine_difference_still_flagged(self):
+        # A real difference (here, NOT NULL toggled) on an otherwise
+        # identical BIGSERIAL column must still be detected, proving the
+        # fix only suppresses the OID noise and doesn't mask real diffs.
+        source = _make_bigserial_column(defseqrelid=16482, attnotnull=True)
+        target_cols = [
+            _make_bigserial_column(defseqrelid=98213, attnotnull=False)
+        ]
+
+        added = []
+        updated = []
+        SchemaDiffTableCompare.compare_target_cols(
+            source, target_cols, added, updated)
+
+        self.assertEqual(len(updated), 1)
+        self.assertEqual(updated[0]['name'], 'adl_id')
+        self.assertEqual(added, [])