Skip to content

Latest commit

 

History

History
116 lines (87 loc) · 3.47 KB

README.rst

File metadata and controls

116 lines (87 loc) · 3.47 KB
Raw

PyHive

PyHive is a collection of Python DB-API and SQLAlchemy interfaces for Presto and Hive.

Usage

DB-API

from pyhive import presto
cursor = presto.connect('localhost').cursor()
cursor.execute('SELECT * FROM my_awesome_data LIMIT 10')
print cursor.fetchone()
print cursor.fetchall()

DB-API (asynchronous)

from pyhive import hive
from TCLIService.ttypes import TOperationState
cursor = hive.connect('localhost').cursor()
cursor.execute('SELECT * FROM my_awesome_data LIMIT 10', async=True)

status = cursor.poll().operationState
while status in (TOperationState.INITIALIZED_STATE, TOperationState.RUNNING_STATE):
    logs = cursor.fetch_logs()
    for message in logs:
        print message

    # If needed, an asynchronous query can be cancelled at any time with:
    # cursor.cancel()

    status = cursor.poll().operationState

print cursor.fetchall()

SQLAlchemy

First install this package to register it with SQLAlchemy (see setup.py).

from sqlalchemy import *
from sqlalchemy.engine import create_engine
from sqlalchemy.schema import *
engine = create_engine('presto://localhost:8080/hive/default')
logs = Table('my_awesome_data', MetaData(bind=engine), autoload=True)
print select([func.count('*')], from_obj=logs).scalar()

Note: query generation functionality is not exhaustive or fully tested, but there should be no problem with raw SQL.

Passing session configuration

# DB-API
hive.connect('localhost', configuration={'hive.exec.reducers.max': '123'})
presto.connect('localhost', session_props={'query_max_run_time': '1234m'})
# SQLAlchemy
create_engine(
    'hive://user@host:10000/database',
    connect_args={'configuration': {'hive.exec.reducers.max': '123'}},
)

Requirements

Install using

  • pip install pyhive[hive] for the Hive interface and
  • pip install pyhive[presto] for the Presto interface.

PyHive works with

  • Python 2.7
  • For Presto: Presto install
  • For Hive: HiveServer2 daemon

There's also a third party Conda package.

Changelog

See https://github.com/dropbox/PyHive/releases.

Contributing

  • Please fill out the Dropbox Contributor License Agreement at https://opensource.dropbox.com/cla/ and note this in your pull request.
  • Changes must come with tests, with the exception of trivial things like fixing comments. See .travis.yml for the test environment setup.

Testing

http://codecov.io/github/dropbox/PyHive/coverage.svg?branch=master

Run the following in an environment with Hive/Presto:

./scripts/make_test_tables.sh
virtualenv --no-site-packages env
source env/bin/activate
pip install -e .
pip install -r dev_requirements.txt
py.test

WARNING: This drops/creates tables named one_row, one_row_complex, and many_rows, plus a database called pyhive_test_database.