問題描述

    AWSDynamoDBObjectMapper *dynamoDBObjectMapper = [AWSDynamoDBObjectMapper defaultDynamoDBObjectMapper];
    AWSDynamoDBScanExpression *scanExpression = [AWSDynamoDBScanExpression new];
    scanExpression.exclusiveStartKey = nil;
    scanExpression.limit = @20;
    [[[dynamoDBObjectMapper scan:[DDBTableRow class]
                      expression:scanExpression]
      continueWithExecutor:[BFExecutor mainThreadExecutor] withSuccessBlock:^id(BFTask *task) { ................

我能夠掃描并返回從我的 DynamoDB 的特定表中記錄的前 20 個(gè)，如上面的一段代碼所示.

I am able to scan through and return the first 20 recorded from a specific table from my DynamoDB as shows on a piece of code above.

現(xiàn)在的問題是我想添加一個(gè) scanExpression.scanFilter = 屬性，但我還沒有找到關(guān)于如何構(gòu)建它的任何好的方向.我在 xcode6

The question now is I want to add a scanExpression.scanFilter = property but I haven't find any good direction on how to build that. I am using AWSiOSSDKv2 aws sdk for iOS on xcode6

這是我目前所擁有的.還沒有完成:

here is what I have so far. It is not complete yet:

    AWSDynamoDBCondition *condition = [AWSDynamoDBCondition new];
    AWSDynamoDBAttributeValue *attribute = [AWSDynamoDBAttributeValue new];
    attribute.N = @"400";
    condition.comparisonOperator = AWSDynamoDBComparisonOperatorEQ;

    NSDictionary *scanFilter = @{@"lat":
                                     @{@"AttributeValueList":attribute,
                                       @"ComparisonOperator":@1}
                                 };
    scanExpression.scanFilter = scanFilter;

推薦答案

可以如下使用:

AWSDynamoDBCondition *condition = [AWSDynamoDBCondition new];
AWSDynamoDBAttributeValue *attribute = [AWSDynamoDBAttributeValue new];
attribute.N = @"400";
condition.attributeValueList = @[attribute];
condition.comparisonOperator = AWSDynamoDBComparisonOperatorEQ;
scanExpression.scanFilter = @{@"lat": condition};

這篇關(guān)于在objective-c中帶有掃描過濾器的dynamodb scanexpression的文章就介紹到這了，希望我們推薦的答案對(duì)大家有所幫助，也希望大家多多支持html5模板網(wǎng)！