docs: function(className, requestedData, callback) {
          /**
           * Callback for QB.data.delete(className, requestedData, callback)
           * @callback deletedDataCallback
           * @param {object} error - The error object
           * @param {object|null} response
           * @param {array} response.deleted - Array of ids of deleted records. If you delete BY CRITERIA this property will be null.
           * @param {number} response.deletedCount - count of deleted records.
           */
          var typesData = {
              id: 1,
              ids: 2,
              criteria: 3
          };
  
          var requestedTypeOf;
  
          var responceNormalized = {
              deleted: [],
              deletedCount: 0
          };
  
          var ajaxParams = {
              type: 'DELETE',
              dataType: 'text'
          };
  
          /** Define what type of data passed by client */
          if(typeof requestedData === 'string') {
              requestedTypeOf = typesData.id;
          } else if(Utils.isArray(requestedData)) {
              requestedTypeOf = typesData.ids;
          } else if(Utils.isObject(requestedData)) {
              requestedTypeOf = typesData.criteria;
          }
  
          if(requestedTypeOf === typesData.id) {
              ajaxParams.url = Utils.getUrl(config.urls.data, className + '/' + requestedData);
          } else if(requestedTypeOf === typesData.ids) {
              ajaxParams.url = Utils.getUrl(config.urls.data, className + '/' + requestedData.toString());
          } else if(requestedTypeOf === typesData.criteria) {
              ajaxParams.url = Utils.getUrl(config.urls.data, className + '/by_criteria');
              ajaxParams.data = requestedData;
          }
  
          function handleDeleteCO(error, result) {
              if (error) {
                  callback(error, null);
              } else {
                  var response;
  
                  if(requestedTypeOf === typesData.id) {
                      responceNormalized.deleted.push(requestedData);
                      responceNormalized.deletedCount = responceNormalized.deleted.length;
                  } else if(requestedTypeOf === typesData.ids) {
                      response = JSON.parse(result);
                      responceNormalized.deleted = response.SuccessfullyDeleted.ids.slice(0);
                      responceNormalized.deletedCount = responceNormalized.deleted.length;
                  } else if(requestedTypeOf === typesData.criteria) {
                      response = JSON.parse(result);
                      responceNormalized.deleted = null;
                      responceNormalized.deletedCount = response.total_deleted;
                  }
  
                  callback (error, responceNormalized);
              }
          }
  
          this.service.ajax(ajaxParams, handleDeleteCO);
      }