Skip to main content

Simple ClickHouse SQLAlchemy Dialect

Project description

ClickHouse SQLAlchemy

ClickHouse dialect for SQLAlchemy to ClickHouse database.

https://img.shields.io/pypi/v/clickhouse-sqlalchemy.svg https://coveralls.io/repos/github/xzkostyan/clickhouse-sqlalchemy/badge.svg?branch=master https://img.shields.io/pypi/l/clickhouse-sqlalchemy.svg https://img.shields.io/pypi/pyversions/clickhouse-sqlalchemy.svg https://img.shields.io/pypi/dm/clickhouse-sqlalchemy.svg https://github.com/xzkostyan/clickhouse-sqlalchemy/actions/workflows/actions.yml/badge.svg

Documentation

Documentation is available at https://clickhouse-sqlalchemy.readthedocs.io.

Usage

Supported interfaces:

  • native [recommended] (TCP) via clickhouse-driver <https://github.com/mymarilyn/clickhouse-driver>

  • async native (TCP) via asynch <https://github.com/long2ice/asynch>

  • http via requests

Define table

from sqlalchemy import create_engine, Column, MetaData

from clickhouse_sqlalchemy import (
    Table, make_session, get_declarative_base, types, engines
)

uri = 'clickhouse+native://localhost/default'

engine = create_engine(uri)
session = make_session(engine)
metadata = MetaData(bind=engine)

Base = get_declarative_base(metadata=metadata)

class Rate(Base):
    day = Column(types.Date, primary_key=True)
    value = Column(types.Int32)

    __table_args__ = (
        engines.Memory(),
    )

Rate.__table__.create()

Insert some data

from datetime import date, timedelta

from sqlalchemy import func

today = date.today()
rates = [
    {'day': today - timedelta(i), 'value': 200 - i}
    for i in range(100)
]

And query inserted data

session.execute(Rate.__table__.insert(), rates)

session.query(func.count(Rate.day)) \
    .filter(Rate.day > today - timedelta(20)) \
    .scalar()

License

ClickHouse SQLAlchemy is distributed under the MIT license.

Supported by

AWS Cloud computing and Security Sponsor Datadog Monitoring Fastly CDN Google Download Analytics Pingdom Monitoring Sentry Error logging StatusPage Status page