ClickHouse JDBC Db session is invalid

Hi everyone!

When I use the following driver, I can’t connect to ClickHouse without specifying the compress=0 parameter because it says db session is invalid:
clickhouse-jdbc-0.6.2.jar

When I use the following driver, I can connect without any parameters:
clickhouse-jdbc-0.6.2-http.jar

This is my JDBC url:
jdbc:clickhouse://host:8123/test_db

What’s the difference between the two?

Hi @Khyle_Vincent_C, welcome to the KNIME forum.

This sounds more like a Clickhouse question than a KNIME one.

Are you able to point us to any clickhouse jdbc documentation (eg you presumably got some guidance somewhere that led you to the “compress=0” parameter), which might help answer the question as to why it is required?

Have you tried using those two drivers outside of KNIME with another opensource jdbc tool such as DBeaver Community, to see if it behaves any differently?

From a brief web search, I think that the difference in the drivers is the protocols used to access the database. One is likely to be a native jdbc driver whilst the other interacts with the database via http (using a REST api).

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