diff --git a/internal/dbutil/testing.go b/internal/dbutil/testing.go
index 0b81687..378f913 100644
--- a/internal/dbutil/testing.go
+++ b/internal/dbutil/testing.go
@@ -34,7 +34,7 @@ func NewTestDB(t *testing.T, migrationTables ...interface{}) (testDB *gorm.DB, c
 		dsn = os.ExpandEnv("$DB_USER:$DB_PASSWORD@tcp($DB_HOST:$DB_PORT)/$DB_DATABASE?charset=utf8mb4&parseTime=True&loc=Local")
 		dialectFunc = mysql.Open
 	case "postgres":
-		dsn = os.ExpandEnv("host=$DB_HOST user=$DB_USER password=$DB_PASSWORD port=$DB_PORT sslmode=disable TimeZone=Asia/Shanghai")
+		dsn = os.ExpandEnv("host=$DB_HOST user=$DB_USER password=$DB_PASSWORD dbname=$DB_DATABASE port=$DB_PORT sslmode=disable TimeZone=Asia/Shanghai")
 		dialectFunc = postgres.Open
 	default:
 		t.Fatalf("Unknown database type: %q", dbType)
@@ -111,7 +111,15 @@ func NewTestDB(t *testing.T, migrationTables ...interface{}) (testDB *gorm.DB, c
 		}
 
 		for _, table := range tables {
-			err := testDB.WithContext(ctx).Exec(`TRUNCATE TABLE ` + QuoteIdentifier(dbType, table)).Error
+			var query string
+			switch dbType {
+			case "mysql":
+				query = `TRUNCATE TABLE ` + QuoteIdentifier(dbType, table)
+			case "postgres":
+				query = `TRUNCATE TABLE ` + QuoteIdentifier(dbType, table) + ` RESTART IDENTITY CASCADE`
+			}
+
+			err := testDB.WithContext(ctx).Exec(query).Error
 			if err != nil {
 				return err
 			}