Question

我在使用Cassandra数据库的Linux平台上。我想使用远程服务器上的Python代码将图像数据插入到Cassandra数据库中。以前，我编写了一个python代码，用于将Images的数据从远程服务器插入MySQL数据库。请参阅下面的MySQL代码

#!/usr/bin/python
# -*- coding: utf-8 -*-
import MySQLdb as mdb
import psycopg2
import sys
import MySQLdb
def read_image(i):   
    filename="/home/faban/Downloads/Python/Python-Mysql/images/im"
    filename=filename+str(i)+".jpg"
    print(filename)
    fin = open(filename)    
    img = fin.read()   
    return img
con = MySQLdb.connect("192.168.50.12","root","faban","experiments" )  
with con:
    print('connecting to database')
    range_from=input('Enter range from:')
    range_till=input('Enter range till:')
    for i in range(range_from,range_till):
     cur = con.cursor()
     data = read_image(i)
     cur.execute("INSERT INTO images VALUES(%s, %s)", (i,data, ))
     cur.close()
     con.commit()
con.close()

此代码成功将数据插入到位于.12的MySQL数据库中我想修改相同的代码以将数据插入到Cassandra数据库中，该数据库也位于.12 在这方面请帮帮我。

Answer 1

如果我创建一个这样的简单表：

CREATE TABLE stackoverflow.images (
    name text PRIMARY KEY,
    data blob);

我可以使用与您类似的Python代码加载这些图像，但是使用DataStax Python Cassandra驱动程序（pip install cassandra-driver）进行一些小的更改：

#imports for DataStax Cassandra driver and sys
from cassandra.cluster import Cluster
from cassandra.auth import PlainTextAuthProvider
from cassandra.cluster import SimpleStatement
import sys

#reading my hostname, username, and password from the command line; defining my Cassandra keyspace as as variable.
hostname=sys.argv[1]
username=sys.argv[2]
password=sys.argv[3]
keyspace="stackoverflow"

#adding my hostname to an array, setting up auth, and connecting to Cassandra
nodes = []
nodes.append(hostname)
auth_provider = PlainTextAuthProvider(username=username, password=password)
ssl_opts = {}
cluster = Cluster(nodes,auth_provider=auth_provider,ssl_options=ssl_opts)
session = cluster.connect(keyspace)

#setting my image name, loading the file, and reading the data
name = "IVoidWarranties.jpg"
fileHandle = open("/home/aploetz/Pictures/" + name)
imgData = fileHandle.read()

#preparing and executing my INSERT statement
strCQL = "INSERT INTO images (name,data) VALUES (?,?)"
pStatement = session.prepare(strCQL)
session.execute(pStatement,[name,imgData])

#closing my connection
session.shutdown()

希望有所帮助！

使用Python填充Cassandra数据库

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