PyClickHouseMigrate

PyClickHouseMigrate is simple tool for manage your ClickHouse migrations.

Inspired by dbmate and aerich.

Install

➜ pip install py-clickhouse-migrator

Usage

Init migrations directory.

By default migrator will create and use ./db/migrations.

➜ migrator --url=clickhouse://[email protected]:9000/default init

As you can see ClickHouse url passed with --url param.

If you want to change migrations path then you can use --path parameter.

➜ migrator --path=./your_path/migrations  --url=clickhouse://[email protected]:9000/default init

After initializitaion make sure you the folders will created.

➜ tree db

db
├── migrations
└── schema.sql

Create new migration

For creation new migrations you need new command.

➜  migrator --url=...  new first_migration

Migration ./db/migrations/202401080000_first_migration.py has been created.

And after this you can find empty migration inside db directory:

➜ tree db
db
├── migrations
│   └── 202401080000_first_migration.py
└── schema.sql

Apply new migration

To apply new migrations you need up command.

Apply all new migrations:

➜  migrator --url=...  up

Apply N new migrations (the next after the last applied):

➜  migrator --url=...  up N

Rollback

To rollback migrations you need rollback command.

Rollback last applied migration:

➜  migrator --url=...  rollback

Rollback N migrations (the next after the last applied):

➜  migrator --url=...  rollback N

View all migrations

To see all migrations (including unapplied) you can use show command.

➜  migrator --url=...  show

[✔] 202404081721_drop_some_column.py (HEAD)
...
[✔] 202401261452_new_column.py
[✔] 202401151114_one_more_table.py
[✔] 202401091440_new_table.py
[✔] 202312261318_init.py

Applied: 21
Pending: 0

Here you can also see the last applied migration (HEAD).

Actual schema of database

Actual schema of database is always stored in the schema.sql in the folder where all your migrations are located. (by default its /db)

➜ tree db
db
├── migrations
│   └── 202401080000_init.py
└── schema.sql # here you can find CREATE TABLE for any table of current database