DynamoDB查询具有以下详细信息的索引：

Question

我的DynamoDB表确实具有一个索引名称：具有分区键的countryStateBusinessUnit-submittedAtId-index是countryStateBusinessUnit（字符串），而排序键是submittedAtId（字符串）。

Sample of record is : 

{
    "actionRequested": "Approve",
    "altMobileNo": null,
    "appState": "Approved",
  "businessUnit": "DStv",
  "comments": "test2",
  "company": {
    "dealerNo": " ",
    "id": " ",
    "name": " "
  },
  "country": "MOZ",
  "countryStateBusinessUnit": "MOZ\*Approved\*DStv",
  "dob": "1992-02-05",
  "email": true,
  "emailAddress": "declankelly1@gmail.com",
  "firstName": "shana",
  "id": "e7a48235-638f-436c-ac67-a4260891c22a",
  "idPassportLoc": "http://location.jpg",
  "lang": "en",
  "lastName": "shamase",
  "loc1": {
    "lat": "-19.570135",
    "lon": "34.72598070000004",
    "name": "213, Dondo, Mozambique"
  },
  "loc2": {
    "lat": "-18.9480626",
    "lon": "32.85425220000002",
    "name": "6, Manica, Mozambique"
  },
  "mobileNo": "+258 11 111 1111",
  "photoLoc": "http://location.jpg",
  "refNo": "BOE-41-TXY",
  "sms": false,
  "submittedAt": "2017-06-12T14:22:02.674Z",
  "submittedAtId": "2017-06-12T14:22:02.674Z\*e7a48235-638f-436c-ac67-a4260891c22a",
  "tools": [
    {
      "code": "Toolbox",
      "owned": true
    },
    {
      "code": "cableclips",
      "owned": true
    },
    {
      "code": "cablecutter",
      "owned": true
    },
    {
      "code": "cablestrippers",
      "owned": true
    },
    {
      "code": "cableties",
      "owned": true
    },
    {
      "code": "compressionf",
      "owned": true
    },
    {
      "code": "compressiontool",
      "owned": true
    },
    {
      "code": "drillingmachine",
      "owned": true
    },
    {
      "code": "fieldstrengthmeter",
      "owned": true
    },
    {
      "code": "fishtape",
      "owned": true
    },
    {
      "code": "hammer",
      "owned": true
    },
    {
      "code": "insulationtape",
      "owned": true
    },
    {
      "code": "screwdriver",
      "owned": true
    },
    {
      "code": "spanners",
      "owned": true
    },
    {
      "code": "stanley",
      "owned": true
    },
    {
      "code": "stepladder",
      "owned": true
    }
  ],
  "trainingConfirmed": [
    {
      "code": "CustomerService",
      "confirmed": true,
      "proofLocation": "https://location.jpg"
    },
    {
      "code": "one_training",
      "confirmed": true,
      "proofLocation": "https://location.jpg"
    },
    {
      "code": "two_training",
      "confirmed": true,
      "proofLocation": "https://location.jpg"
    },
    {
      "code": "product_knowledge",
      "confirmed": true,
      "proofLocation": "https://location.jpg"
    },
    {
      "code": "sales",
      "confirmed": true,
      "proofLocation": "https://location.jpg"
    },
    {
      "code": "abc_dealer",
      "confirmed": true,
      "proofLocation": "https://location.jpg"
    },
    {
      "code": "vms",
      "confirmed": true,
      "proofLocation": "https://location.jpg"
    }
  ],
  "trainingRequested": [
    {
      "code": "two_training",
      "levelCode": true,
      "requested": true
    },
    {
      "code": "abc_dealer",
      "levelCode": null,
      "requested": true
    }
  ],
  "tsAndCsAccepted": true,
  "updatedAt": "2018-02-09T08:04:30.868Z"
}

我尝试使用下面的查询，但是没有用：

    requestParam = {
                TableName: stages.toStageQualifiedResourceName(config.ICApplicationTableName, context.stage, context),
                IndexName: "country-state-index",
                KeyConditionExpression: "country = :cntry and #state = :state",
                ExpressionAttributeNames:{
                    "#state": "state"
                },
                ExpressionAttributeValues: {
                    ":cntry": request.countryId.toUpperCase(),
                    ":state": request.appState
                },
                ProjectionExpression: "id, firstName, lastName, appState, dob, submittedAt, company, businessUnit, updatedAt",
                Limit: request.limit,
                ScanIndexForward: false
            };

            if (fromDate && toDate) {
                requestParam.ExpressionAttributeValues[":fromDte"] = fromDate;
                requestParam.ExpressionAttributeValues[":toDte"] = toDate;
                requestParam['FilterExpression'] = "submittedAtId > :fromDte and submittedAtId < :toDte";
            }
            else {
                if (fromDate || toDate) {
                    if (fromDate) {
                        requestParam.ExpressionAttributeValues[":fromDte"] = fromDate;
                        requestParam['FilterExpression'] = "submittedAtId > :fromDte";
                    }
                    if (toDate) {
                        requestParam.ExpressionAttributeValues[":toDte"] = toDate;
                        requestParam['FilterExpression'] = "submittedAtId < :toDte";

                    }
                }
            }
        }

if (request.exclusiveStartKey && request.exclusiveStartKey.trim().length > 0) {
        var exKey = request.exclusiveStartKey.split(",");
        requestParam.ExclusiveStartKey = {
            id: exKey[0],
            submittedAtId: exKey[1],
            countryStateBusinessUnit: exKey[2]
        };
    }

有人可以告诉我如何从＆到日期查询国家，州（appState）和可选（我们将与SubmittedAt或SubmittedAtId进行比较）。我还用以下详细信息创建了一个索引：

另一个新的索引名称：具有分区键的country-state-index是country（String），排序键是state（String）。请让我知道没有businessUnit时如何查询？