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latenightcoding

Wonder if there is anything like this for ClickHouse.

edit: to query pg from clickhouse not clickhouse from duckdb

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Yes, ClickHouse can query Postgres for maybe two years already.

https://clickhouse.com/docs/en/integrations/postgresql/postg...

You can connect to Postgres using a table function:

SELECT ... FROM postgresql(...)

You can create a table with ENGINE = PostgreSQL and use it like a normal table.

You can create a database with ENGINE = PostgreSQL and it will represent all the tables from the PostgreSQL database.

And finally, you can replicate data from PostgreSQL in realtime with CDC into ClickHouse tables.

Similar features available for MySQL, MongoDB and SQLite.

What is surprising: if you query MySQL from ClickHouse, the queries work faster despite the fact that the data is simply read from MySQL.

And two more use-cases: - you can create a table in ClickHouse pointing to multiple MySQL servers for sharding and failover, so ClickHouse can be used to query sharded MySQL; - you can create a key-value dictionary on top of MySQL tables and use it in JOINs.

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