Clickhouse Cluster

Clickhouse cluster with 2 shards and 2 replicas built with docker-compose.

Not for production use.

Run

Run single command, and it will copy configs for each node and run clickhouse cluster company_cluster with docker-compose

make config up

Containers will be available in docker network 172.23.0.0/24

Profiles

• default - no password
• admin - password 123

Test it

Login to clickhouse01 console (first node's ports are mapped to localhost)

clickhouse-client -h localhost

Or open clickhouse-client inside any container

docker exec -it clickhouse01 clickhouse-client -h localhost

Create a test database and table (sharded and replicated)

CREATE DATABASE company_db ON CLUSTER 'company_cluster';

CREATE TABLE company_db.events ON CLUSTER 'company_cluster' (
    time DateTime,
    uid  Int64,
    type LowCardinality(String)
)
ENGINE = ReplicatedMergeTree('/clickhouse/tables/{cluster}/{shard}/events', '{replica}')
PARTITION BY toDate(time)
ORDER BY (uid);

CREATE TABLE company_db.events_distr ON CLUSTER 'company_cluster' AS company_db.events
ENGINE = Distributed('company_cluster', company_db, events, uid);

Load some data

INSERT INTO company_db.events_distr VALUES
    ('2020-01-01 10:00:00', 100, 'view'),
    ('2020-01-01 10:05:00', 101, 'view'),
    ('2020-01-01 11:00:00', 100, 'contact'),
    ('2020-01-01 12:10:00', 101, 'view'),
    ('2020-01-02 08:10:00', 100, 'view'),
    ('2020-01-03 13:00:00', 103, 'view');

Check data from the current shard

SELECT * FROM company_db.events;

Check data from all cluster

SELECT * FROM company_db.events_distr;

Add more nodes

If you need more Clickhouse nodes, add them like this:

1. Add replicas/shards to config.xml to the block company/remote_servers/company_cluster.
2. Add nodes to docker-compose.yml.
3. Add nodes in Makefile in config target.

Start, stop

Start/stop the cluster without removing containers

make start
make stop

Teardown

Stop and remove containers

make down