_ci =& get_instance(); // get code igniter instance // get zgvdatum of prestudent $this->_ci->load->model('crm/Prestudent_model', 'PrestudentModel'); $this->_ci->PrestudentModel->addSelect('zgvdatum, zgvmadatum'); $prestudentRes = $this->_ci->PrestudentModel->load($params['prestudent_id']); if (isError($prestudentRes)) return $prestudentRes; if (hasData($prestudentRes)) { $prestudentData = getData($prestudentRes)[0]; // get and compare zgvdatum and zgvmadatum $zgvdatum = $prestudentData->zgvdatum; if (isEmptyString($zgvdatum)) return success(false); $zgvmadatum = $prestudentData->zgvmadatum; if (isEmptyString($zgvmadatum)) return success(false); // check if zgvmadatum comes after zgvdatum if ($zgvmadatum < $zgvdatum) return success(false); else return success(true); } else return success(false); } }