如何检查dynamodb中的字符串集中是否存在字符串

How to check a string exist in string set in dynamodb(如何检查dynamodb中的字符串集中是否存在字符串)

问题描述

我在表中的每个项目中都设置了一个字符串.例如，

I have a string set in each item in my table. For example,

{                                        
   Title = "Qm9vayAxMDEgVGl0bGU="
   ISBN = "111-1111111111"
   Authors = "Author 1"
   Price = -2
   Dimensions = "8.5 x 11.0 x 0.5"
   PageCount = 500
   Color = [ "Red", "Black" ]
   ProductCategory = "Book" 
}


{                                        
   Title = "Qm9vayAxMDIgVGl0bGU="
   ISBN = "222-222222222"
   Authors = "Author 2"
   Price = -8
   Dimensions = "8.5 x 11.0 x 0.5"
   PageCount = 700
   Color = [ "Red", "Green" ]
   ProductCategory = "Book" 
}

使用 dynamoDB php sdk，我想获得红色"颜色的项目.我试试这样.

With dynamoDB php sdk, I want to get items which is "Red" color. I try like this.

$response = $client->query(array(
    "TableName" => $tablename,
    "KeyConditions" => array(
        "ComparisonOperator" => ComparisonOperator::CONTAINS,
        'Color' => array(
            'AttributeValueList' => array(
                array(Type::STRING_SET => array("Red"))
        ),
     )
));

但我遇到了这样的错误.

But I got an error like that.

ValidationException: One or more parameter values were invalid: ComparisonOperator CONTAINS is not valid for SS AttributeValue type

推荐答案

我从 aws 开发者论坛找到了一个解决方案 这里.不能将 CONTAINS 与 query 一起使用.必须与 scan 一起使用.就这样.

I found a solution from aws developer forum here. Can't use CONTAINS with query. Have to use it with scan. Like that.

$response = $client->scan(array(
    "TableName" => $tablename,
    "KeyConditions" => array(
        "ComparisonOperator" => ComparisonOperator::CONTAINS,
        'Color' => array(
            'AttributeValueList' => array(
                array(Type::STRING => "Red")
        ),
     )
));

这篇关于如何检查dynamodb中的字符串集中是否存在字符串的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！