如何在dynamodb查询中使用保留关键字'year'

Question

我试图从dynamodb代表年份（保留关键字）获取记录。

但无法取得成功。

DynamoDBScanExpression queryExpression = new DynamoDBScanExpression();
queryExpression.withFilterExpression("year = :year).withExpressionAttributeValues(valueMap);
result = dynamoDBTemplate.scan(ABC.class, queryExpression);

Answer 1

      DynamoDBScanExpression queryExpression = new DynamoDBScanExpression();

      Map<String, AttributeValue> valueMap = new HashMap<>();

     valueMap.put(":year", new AttributeValue().withS(2016));

    queryExpression.withFilterExpression("#y = :year).

   .withExpressionAttributeValues(valueMap);

   Map<String, String> expression = new HashMap<>();

            expression.put("#y", "year");

     queryExpression.withExpressionAttributeNames(expression);

解决了我的问题。

Answer 2

Map<String, String> rwnm = new HashMap();
rwnm.put("#a", "action");

QuerySpec querySpec = new QuerySpec();
querySpec.withFilterExpression("#a > :action");
querySpec.withNameMap(rwnm);
querySpec.withValueMap(new ValueMap().withString(":action", "LightsOn"));