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我在使用 dynamodb 时遇到问题。我正在尝试验证其中包含的数据，但扫描似乎只返回数据的一个子集，这是我与 python boto 绑定一起使用的代码

#!/usr/bin/python
#Check the scanned length of a table against the Table Description
import boto.dynamodb
#Connect
TABLENAME = "MyTableName"
sdbconn = boto.dynamodb.connect_to_region(
    "eu-west-1",
    aws_access_key_id='-snipped-',
    aws_secret_access_key='-snipped-')

#Initial Scan
results = sdbconn.layer1.scan(TABLENAME,count=True)
previouskey = results['LastEvaluatedKey']

#Create Counting Variable
count = results['Count']

#DynamoDB scan results are limited to 1MB but return a Key value to carry on for the next MB
#so loop untill it does not return a continuation point
while previouskey != False:
    results = sdbconn.layer1.scan(TABLENAME,exclusive_start_key=previouskey,count=True)
    print(count)
    count = count + results['Count']
    try:
        #get next key
        previouskey = results['LastEvaluatedKey']
    except:
        #no key returned so thats all folks!
        print(previouskey)
        print("Reached End")
        previouskey = False

#these presumably should match, they dont on the MyTableName Table, not even close
print(sdbconn.describe_table(TABLENAME)['Table']['ItemCount'])
print(count)

print(sdbconn.describe_table)给我 1748175 和 print(count)583021。我的印象是这些应该总是匹配？（我知道 6 小时更新）在过去 24 小时内只添加了 300 行，但有人知道这是否是 dynamodb 的问题吗？还是我的代码有错误的假设？

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1 回答 1

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终于弄明白了，它与本地二级索引有关，它们在表描述中显示为唯一项目，该表有两个 LSI 导致它显示的项目数量是实际存在的项目数量的 3 倍

于 2013-10-29T10:31:15.140 回答