Question

我正在尝试执行一个查询，我想要检索所有具有2个定义值之间的高度和宽度的项目，如下所示：

let queryExpression = AWSDynamoDBQueryExpression()

queryExpression.filterExpression = ":widthSmall < #width < :width AND :heightSmall < #height < :height"
queryExpression.keyConditionExpression = "#addedByType = :addedByType"
queryExpression.expressionAttributeNames = ["#addedByType": "addedByType", "#width": "widthSmall","#height": "heightSmall","#width": "width","#height": "height"]
queryExpression.expressionAttributeValues = [":addedByType": "APPUSER", ":widthSmall": 50, ":heightSmall": 50, ":width": 100, ":height": 100]

queryExpression.scanIndexForward = false
queryExpression.limit = 200

这会因为expressionAttributeNames

而抛出以下错误

fatal error: Dictionary literal contains duplicate keys

检查的正确方法是什么？

Answer 1

好的，经过相当多的试验和错误，我已经弄清楚我做错了什么，并得出以下结果：

queryExpression.filterExpression = ":widthSmall < #width1 AND #width < :width AND :heightSmall < #height1 AND #height < :height"
queryExpression.keyConditionExpression = "#addedByType = :addedByType"
queryExpression.expressionAttributeNames = ["#addedByType": "addedByType", "#width1": "width","#height1": "height", "#width": "width", "#height": "height"]
queryExpression.expressionAttributeValues = [":addedByType": "APPUSER", ":widthSmall": 50, ":heightSmall": 50, ":width": 101, ":height": 101]

问题是我在词典中引用了两次相同的键

具有开始和结束值的AWS DynamoDB查询

1 个答案: