python-driver | DataStax Python Driver for Apache Cassandra
kandi X-RAY | python-driver Summary
kandi X-RAY | python-driver Summary
DataStax Python Driver for Apache Cassandra
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Top functions reviewed by kandi - BETA
- Perform an update statement
- Adds a query to the batch
- Get a connection to the pool
- Execute a statement
- Benchmark a connection
- Execute a query asynchronously
- Parse command line options
- Bind values to values
- Return True if i is a routing key index
- Appends UNSET_VALUE
- Send a query to the proxy
- Serialize the value to a buffer
- Updates the model
- Runs the loop once
- Deserialize a DateRange
- Save this instance to the database
- Create a Cassandra protocol handler for the given column parser
- Decode a message
- Return a connection from the pool
- Run setup
- Populate the trace
- Query the database
- Process an options response
- Prepare a query
- Murmurmur3 hash function
- Main loop
- Handle a startup response
python-driver Key Features
python-driver Examples and Code Snippets
Lines of Code : 145License : Permissive (MIT)
Copyfrom playhouse.cockroachdb import CockroachDatabase
db = CockroachDatabase('my_app', user='root', host='10.1.0.8')
db = CockroachDatabase('postgresql://root:secret@host:26257/defaultdb...')
db = CockroachDatabase(
'my_app',
user='root',
from bno055_usb_stick_py import BnoUsbStick
bno_usb_stick = BnoUsbStick()
reg_addr = 0x00
reg_val = bno_usb_stick.read_register(reg_addr)
print(f"bno chip id addr: 0x{reg_addr:02X}, value: 0x{reg_val:02X}")
from bno055_usb_stick_py import BnoUsbStic from rethinkdb import r
import trio
async def main():
r.set_loop_type('trio')
async with trio.open_nursery() as nursery:
async with r.open(db='test', nursery=nursery) as conn:
await r.table_create('marvel').run(conn)
# -*- coding: utf-8 -*-
#
# Copyright 2012-2015 Spotify AB
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www connection.setup(["http://myserver.myname.com"], "cqlengine", protocol_version=3)
connection.setup(["myserver.myname.com"], "cqlengine", protocol_version=3)
from cassandra.cluster import Cluster
cluster = Cluster(['127.0.0.1'])
session = cluster.connect()
rows = session.execute("select * from jaeger_v1_test.traces")
trace = rows[0]
hexstr = ''.join('{:02x}'.format(x) for x in trace.trace_id)
#!/bin/bash
packageName=$1
destinationPath=$2
configLocation=$3
mkdir /tmp/$packageName
pip download $packageName -d /tmp/$packageName
zip -r $destinationPath/$packageName.zip /tmp/$packageName/* $configLocation
rm -rf /tmp/$packageName
UPDATE test,tbl SET val = val + ? where name = ? and id = ?;
bs = bind(ps, [set(['name']), 'name', 1])
from cassandra.cqlengine import columns
from cassandra.cqlengine.usertype import UserType
from django.db import connections
from cassandra.cluster import UserTypeDoesNotExist
class UserAddress(UserType)
street = columns.Text()
*** Test Cases ***
Forloop method
:FOR ${i} IN RANGE ${row}
\ Log ${i}
Community Discussions
Trending Discussions on python-driver
QUESTION
To archive this using Cassendra Shell :
...ANSWER
Answered 2022-Mar-24 at 10:28The metrics in nodetool tablestats (formerly cfstats) is not exposed to the drivers so you cannot get this information via CQL.
These metrics are only exposed via JMX. Cheers!
QUESTION
I am attempting to query neo4j for an average score, aggregated by month.
BackgroundThe date attribute in my DB is set as epoch timestamp.
Work so farI have the following code so far
...ANSWER
Answered 2021-Mar-06 at 05:13The simplest thing is to aggregate by year and month:
QUESTION
I am having trouble parallelizing code that reads some files and writes to neo4j.
- I am using dask to parallelize the process_language_files function (3rd cell from the bottom).
- I try to explain the code below, listing out the functions (First 3 cells).
- The errors are printed at the end (Last 2 cells).
- I am also listing environments and package versions at the end.
If I remove dask.delayed and run this code sequentially, its works perfectly well.
Thank you for your help. :)
==========================================================================
Some functions to work with neo4j.
...ANSWER
Answered 2021-Jan-12 at 08:07You are getting this error because you are trying to share the driver object amongst your worker.
The driver object contains private data about the connection, data that do not make sense outside the process (and also are not serializable).
It is like trying to open a file somewhere and share the file descriptor somewhere else. It won't work because the file number makes sense only within the process that generates it.
If you want your workers to access the database or any other network resource, you should give them the directions to connect to the resource.
In your case, you should not pass the global_driver as a parameter but rather the connection parameters and let each worker call get_driver to get its own driver.
QUESTION
I am trying to write to DB tables and currently hardcoding the schema name in every query i.e. awesome_schema.book. Unfortunately, now I have to set this schema name in all the queries :-(
Is there a way to set it in the connector or cursor level and not tangle the queries with schema name.
Can anyone please suggest what would be the option for my case.
How to set the schema while running code from python.
...ANSWER
Answered 2021-Jan-07 at 07:32Redshift (and PostgreSQL) has the SET search_path TO some_schema syntax that might be a possible solution for your use case.
https://docs.aws.amazon.com/redshift/latest/dg/r_search_path.html
QUESTION
In my Python (3.8) application, I make a request to the Cassandra database via DataStax Python Driver 3.24.
I have several CQL operations that I am trying to execute with a single query via BatchStatement according to the official documentation. Unfortunately, my code causes an error with the following content:
...ANSWER
Answered 2020-Dec-15 at 06:12Well, I finally found the error.
I removed the retry_policy property from the BatchStatement. Then my mistake was that I put CQL arguments inside SimpleStatement.
Here is working example code snippet:
QUESTION
I have encountered very strange behavior and am trying to understand in which cases this may occur. In my Python application, I access the Cassandra database via the driver.
As you can see below, first, I do an INSERT operation, which creates a record in the table. Next, I do a SELECT operation that should return the last message that was created earlier. Sometimes the select operation returns empty values to me. I have an assumption that Cassandra has an internal scheduler that takes the INSERT task to work. However, when I try to get the last record through the SELECT operation, the record has not yet been created. Is this possible?
QUESTION:
Is it possible to get a callback from Cassandra after the INSERT operation that the record was created successfully?
SNIPPET:
...ANSWER
Answered 2020-Nov-25 at 10:53When you execute the first insert statement and you get the result, that means Cassandra completed your insert statement.
It looks like you are inserting with consistency level(CL) of LOCAL_QUORUM but CL is not set when you select the same record.
By default, python driver uses LOCAL_ONE for consistency level if it is not set.
In your case, when you insert the record with LOCAL_QUORUM, assuming you have replication factor of 3, then at least 2 replica nodes out of 3 have your data.
(note that Cassandra always tries to write to all the replica nodes.)
And then you query with LOCAL_ONE, you may hit those 2 nodes and get the result, or you may hit the one that failed to write your record.
In order to achieve strong consistency in Cassandra, you have to use LOCAL_QUORUM for reads and writes.
Try using LOCAL_QUORUM for select also, or set the default consistency level to LOCAL_QUORUM through default execution profile: https://docs.datastax.com/en/developer/python-driver/3.24/getting_started/#execution-profiles
QUESTION
>>> from pymongo import MongoClient
>>> client = MongoClient()
>>> db = client['cvedb']
>>> db.list_collection_names()
['cpeother', 'mgmt_blacklist', 'via4', 'capec', 'cves', 'mgmt_whitelist', 'ranking', 'cwe', 'info', 'cpe']
>>> colCVE = db["cves"]
>>> cve = colCVE.find().sort("Modified", -1) # this works
>>> cve_ = colCVE.find().allow_disk_use(True).sort("Modified", -1) # this doesn't work
AttributeError: 'Cursor' object has no attribute 'allow_disk_use'
>>> cve_ = colCVE.find().sort("Modified", -1).allow_disk_use(True) # this doesn't work
AttributeError: 'Cursor' object has no attribute 'allow_disk_use'
>>> cve.allow_disk_use(True) # this doesn't work
AttributeError: 'Cursor' object has no attribute 'allow_disk_use'
>>>
ANSWER
Answered 2020-Oct-20 at 08:57In pymongo, you can use allowDiskUse in combination with aggregate:
QUESTION
In my Python application, I make the query to the Cassandra database. I'm trying to implement pagination through the cassandra-driver package. As you can see from the code below, paging_state returns the bytes data type. I can convert this value to the string data type. Then I send the value of the str_paging_state variable to the client. If this client sends me str_paging_state again I want to use it in my query.
This part of code works:
...ANSWER
Answered 2020-Oct-07 at 15:05Just convert the binary data into hex string or base64 - use binascii module for that. For example, for first case functions hexlify/unhexlify (or in Python 3 use .hex method of binary data), and for base64 - use functions b2a_base64/a2b_base64
QUESTION
I am developing an app using python and Cassandra(Astra provider) and trying to deploy it on Heroku.
The problem is connecting to the database requires the credential zip file to be present locally- https://docs.datastax.com/en/astra/aws/doc/dscloud/astra/dscloudConnectPythonDriver.html '/path/to/secure-connect-database_name.zip' and Heroku does not have support for uploading credentials files.
I can configure the username and password as environment variable but the credential zip file can't be configured as an environment variable.
...ANSWER
Answered 2020-Jun-30 at 06:06If you can checkin secure bundle into repo, then it should be easy - you just need to point to it from the cloud config map, and take username/password from the configured secrets via environment variables:
QUESTION
I have a Node.js application that connects to neo4j. Running it normally works well, I'm able to connect. However, when I run it inside Docker I run into this error:
...ANSWER
Answered 2020-May-14 at 23:26Your docker image runs in an isolated network so it does not have access to your neo4j at localhost:7687
In your javascript file, try changing the url you're connecting to to your host-ip instead of localhost. You can find that with running ip addr show.
Better yet, you can pass host mappings to your container with the --add-host flag - add host to container example
Community Discussions, Code Snippets contain sources that include Stack Exchange Network
Vulnerabilities
No vulnerabilities reported
Install python-driver
You can use python-driver like any standard Python library. You will need to make sure that you have a development environment consisting of a Python distribution including header files, a compiler, pip, and git installed. Make sure that your pip, setuptools, and wheel are up to date. When using pip it is generally recommended to install packages in a virtual environment to avoid changes to the system.
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