fix(db diff): filter inherited constraints for partitioned tables

internal/db/diff/diff.go

@@ -35,6 +35,7 @@ func Run(ctx context.Context, schema []string, file string, config pgconn.Config
 	if err != nil {
 		return err
 	}
+	out = filterInheritedConstraints(out)
 	branch := keys.GetGitBranch(fsys)
 	fmt.Fprintln(os.Stderr, "Finished "+utils.Aqua("supabase db diff")+" on branch "+utils.Aqua(branch)+".\n")
 	if err := SaveDiff(out, file, fsys); err != nil {
@@ -89,6 +90,29 @@ func findDropStatements(out string) []string {
 	return drops
 }
 
+var inheritedConstraintPattern = regexp.MustCompile(`(?i)alter\s+table\s+[^;]+\s+(drop|add)\s+constraint\s+"[^"]*fkey\d+"`)
+
+func filterInheritedConstraints(out string) string {
+	lines, err := parser.SplitAndTrim(strings.NewReader(out))
+	if err != nil {
+		return out
+	}
+	var filtered []string
+	for _, line := range lines {
+		if !inheritedConstraintPattern.MatchString(line) {
+			filtered = append(filtered, line)
+		}
+	}
+	if len(filtered) == 0 {
+		return ""
+	}
+	result := strings.Join(filtered, ";\n\n") + ";"
+	if strings.HasSuffix(out, "\n") {
+		result += "\n"
+	}
+	return result
+}
+
 func CreateShadowDatabase(ctx context.Context, port uint16) (string, error) {
 	// Disable background workers in shadow database
 	config := start.NewContainerConfig("-c", "max_worker_processes=0")

internal/db/diff/diff_test.go

@@ -345,6 +345,68 @@ func TestDropStatements(t *testing.T) {
 	assert.Equal(t, []string{"drop table t", "alter table t drop column c"}, drops)
 }
 
+func TestFilterInheritedConstraints(t *testing.T) {
+	t.Run("filters inherited fkey constraints", func(t *testing.T) {
+		input := `alter table "public"."users" drop constraint "users_avatar_id_fkey1";
+alter table "public"."users" drop constraint "users_avatar_id_fkey2";
+alter table "public"."users" add constraint "users_avatar_id_fkey1" FOREIGN KEY (avatar_id) REFERENCES photos_avatars(id);
+create table test();`
+		result := filterInheritedConstraints(input)
+		assert.Equal(t, "create table test();", result)
+	})
+
+	t.Run("preserves non-inherited constraints", func(t *testing.T) {
+		input := `alter table "public"."users" drop constraint "users_avatar_id_fkey";
+alter table "public"."users" add constraint "users_avatar_id_fkey" FOREIGN KEY (avatar_id) REFERENCES photos(id);`
+		result := filterInheritedConstraints(input)
+		assert.Contains(t, result, `alter table "public"."users" drop constraint "users_avatar_id_fkey"`)
+		assert.Contains(t, result, `alter table "public"."users" add constraint "users_avatar_id_fkey" FOREIGN KEY (avatar_id) REFERENCES photos(id)`)
+	})
+
+	t.Run("returns empty string when all statements filtered", func(t *testing.T) {
+		input := `alter table "public"."users" drop constraint "users_fkey1";
+alter table "public"."users" drop constraint "users_fkey2";`
+		result := filterInheritedConstraints(input)
+		assert.Equal(t, "", result)
+	})
+
+	t.Run("handles empty input", func(t *testing.T) {
+		result := filterInheritedConstraints("")
+		assert.Equal(t, "", result)
+	})
+
+	t.Run("handles mixed statements with partitioned table constraints", func(t *testing.T) {
+		input := `create table accounts(id text primary key);
+alter table "public"."users" drop constraint "users_avatar_id_avatar_bucket_fkey1";
+alter table "public"."users" drop constraint "users_avatar_id_avatar_bucket_fkey14";
+alter table "public"."companies" drop constraint "companies_logo_id_fkey1";
+create index idx_test on test(id);`
+		result := filterInheritedConstraints(input)
+		assert.Contains(t, result, "create table accounts(id text primary key)")
+		assert.Contains(t, result, "create index idx_test on test(id)")
+		assert.NotContains(t, result, "fkey1")
+		assert.NotContains(t, result, "fkey14")
+	})
+
+	t.Run("filters exact bug report pattern", func(t *testing.T) {
+		input := `alter table "public"."users" drop constraint "users_avatar_id_avatar_bucket_fkey1";
+alter table "public"."users" drop constraint "users_avatar_id_avatar_bucket_fkey2";
+alter table "public"."users" drop constraint "users_avatar_id_avatar_bucket_fkey3";
+alter table "public"."users" add constraint "users_avatar_id_avatar_bucket_fkey1" FOREIGN KEY (avatar_id, avatar_bucket) REFERENCES photos_avatars(id, bucket) ON DELETE SET NULL;
+alter table "public"."users" add constraint "users_avatar_id_avatar_bucket_fkey2" FOREIGN KEY (avatar_id, avatar_bucket) REFERENCES photos_brands(id, bucket) ON DELETE SET NULL;`
+		result := filterInheritedConstraints(input)
+		assert.Equal(t, "", result)
+	})
+
+	t.Run("preserves legitimate constraint operations", func(t *testing.T) {
+		input := `alter table "public"."users" drop constraint "users_avatar_id_avatar_bucket_fkey";
+alter table "public"."users" add constraint "users_avatar_id_avatar_bucket_fkey" FOREIGN KEY (avatar_id, avatar_bucket) REFERENCES photos(id, bucket) ON DELETE SET NULL;`
+		result := filterInheritedConstraints(input)
+		assert.Contains(t, result, "users_avatar_id_avatar_bucket_fkey")
+		assert.NotContains(t, result, "fkey1")
+	})
+}
+
 func TestLoadSchemas(t *testing.T) {
 	expected := []string{
 		filepath.Join(utils.SchemasDir, "comment", "model.sql"),

internal/db/diff/pgadmin.go

@@ -44,7 +44,7 @@ func RunPgAdmin(ctx context.Context, schema []string, file string, config pgconn
 		return err
 	}
 
-	return SaveDiff(output, file, fsys)
+	return SaveDiff(filterInheritedConstraints(output), file, fsys)
 }
 
 var output string