src/main/java/com/conveyal/gtfs/loader/TimeField.java
@Override
    public ValidateFieldResult<String> validateAndConvert(String hhmmss) {
        return ValidateFieldResult.from(getSeconds(hhmmss));
    }
@Override
    public ValidateFieldResult<String> validateAndConvert(String hhmmss) {
        return ValidateFieldResult.from(getSeconds(hhmmss));
    }
Actually this is converting the string. Can we use some JDBC existing functions for this?