boto python dynamodb 扫描 attributes_to_get

Question

大家好，

boto的文档说得很模糊，这个操作为什么不成功呢？

from boto.dynamodb2.table import Table
import time

print "Scanning Existing Database"

myTable = Table('myTable')

start = time.clock()

my_query = myTable.scan(scan_filter=None, attributes_to_get=['something'])
results = []
for x in my_query:
    results.append(x['something'])

elapsed = (time.clock() - start)
print "Scan Operation took",elapsed
print len(results)

那为什么这个能成功呢：

#!/bin/env python

import boto
db = boto.connect_dynamodb()

import time

print "Scanning Existing Database"

table = db.get_table('current_fhv_drivers')

start = time.clock()

all_query = table.scan(attributes_to_get=['something'])
results = []
for x in all_query:
    results.append(x['something'])

elapsed = (time.clock() - start)
print "Scan Operation took",elapsed
print len(results)

Answer 1

第一个代码示例如果你在.boto文件中正确设置了配置，就应该能正常运行。这个方法对我的任务是有效的。

Answer 2

看起来你是在尝试在建立连接之前获取一个表格。你可以试试这个：

import boto
import boto.dynamodb2
from boto.dynamodb2.table import Table

conn = boto.dynamodb2.connect_to_region(
    'us-east-1',
    aws_access_key_id=AWS_ACCESS_KEY_ID,
    aws_secret_access_key=AWS_SECRET_ACCESS_KEY
)
myTable = Table('myTable', connection=conn)