> pip install aiochclient

When installing aiochclient will try to build C extensions to boost its speed (about 30% speed up).

aiochclient needs aiohttp.ClientSession for connecting:

from aiochclient import ChClient
from aiohttp import ClientSession


async def main():
    async with ClientSession() as s:
        client = ChClient(s)
        assert await client.is_alive()  # returns True if connection is Ok

await client.execute(
    "CREATE TABLE t (a UInt8, b Tuple(Date, Nullable(Float32))) ENGINE = Memory"
)

For INSERT queries you can pass values as *args. Values should be iterables.

await client.execute(
    "INSERT INTO t VALUES",
    (1, (dt.date(2018, 9, 7), None)),
    (2, (dt.date(2018, 9, 8), 3.14)),
)

For fetching all rows at once use fetch method:

all_rows = await client.fetch("SELECT * FROM t")

For fetching first row from result use fetchrow method:

row = await client.fetchrow("SELECT * FROM t WHERE a=1")
assert row == (1, (dt.date(2018, 9, 7), None))

You can also use fetchval method, which returns first value of the first row from query result:

val = await client.fetchval("SELECT b FROM t WHERE a=2")
assert val == (dt.date(2018, 9, 8), 3.14)

With async iteration on query results steam you can fetch multiple rows without loading them all into memory at once:

async for row in client.iterate(
    "SELECT number, number*2 FROM system.numbers LIMIT 10000"
):
    assert row[0] * 2 == row[1]

ChClient returns rows as tuples.

Use fetch/fetchrow/fetchval for SELECT queries and execute or any of last for INSERT and all another queries.

aiochclient automatically converts values to needed type both from Clickhouse response and for client INSERT queries.

If you want to change connection pool size, you can use aiohttp.TCPConnector. Note that by default pool limit is 100 connections.