Executing a cassandra insert query through Python multiprocessing queue -


i have cassandra keyspace sujata.i connecting cassandra using python driver cassandra.cluster.the column family of sujata hello. following code:-

from multiprocessing import process,queue cassandra.cluster import cluster import os queue=queue() cluster = cluster(['127.0.0.1']) metadata = cluster.metadata session = cluster.connect("sujata")  def hi():     global session     global queue     while true:         y=queue.get()         if y=="exit":             os._exit(0)             else:             print y             session.execute(y)  if __name__=="__main__":     x=process(target=hi)     x.start()     in xrange(10):         z="insert hello(name) values('" + str(i) + "');"         queue.put(z)         if i==9:             queue.put("exit")     session.cluster.shutdown()     session.shutdown()

in table, have column name want insert value of i.the insert query passed through queue.i able contents of queue.when run above code,the output is:-

insert hello(name) values('0');

the session.execute() not working. unable understand why happening.

i don't have cassandra machine, guess, it'll work once move connection part prcoess-function hi(). like:

def hi():     cluster = cluster(['127.0.0.1'])     metadata = cluster.metadata     session = cluster.connect("sujata")     global queue     while true:         y=queue.get()         if y=="exit":             os._exit(0)             else:             print y             session.execute(y)

don't know why it's behaving this, i've seen global variables behaving oddly new processes.

this not best way guess. because each time it'll connect same database redundant , need closed. hope there might better answer.

edit 1:

i didn't read code properly. using queue. process hi start once , queue being used communicate between processes. connection database once only. don't need database connection in main process. shifting part multiprocess function best way.


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