ClickHouse® cluster configuration

• How do I create a user to access a cluster from DataLens with read-only permissions?

• How do I grant a user permissions to create and delete tables or databases?

• How do I find out the internal_replication setting value?

• How do I increase the maximum amount of RAM to run a query?

How do I create a user to access a cluster from DataLens with read-only permissions?How do I create a user to access a cluster from DataLens with read-only permissions?

Follow the guide to create a user with read-only permissions. If the cluster settings have the DataLens access option enabled, the service can connect to the cluster through this user.

How do I grant a user permissions to create and delete tables or databases?How do I grant a user permissions to create and delete tables or databases?

Go to the cluster settings, enable the Managing users via SQL option, and grant the user the appropriate permissions using a GRANT statement.

How do I find out the internal_replication setting value?How do I find out the internal_replication setting value?

The internal_replication setting information is not available in Yandex Cloud interfaces or ClickHouse® system tables. The default setting value is true.

How do I increase the maximum amount of RAM to run a query?How do I increase the maximum amount of RAM to run a query?

If the amount of RAM is not sufficient for running a query, the following error occurs:

DB::Exception: Memory limit (total) exceeded:
would use 14.10 GiB (attempt to allocate chunk of 4219924 bytes), maximum: 14.10 GiB.
(MEMORY_LIMIT_EXCEEDED), Stack trace (when copying this message, always include the lines below)

To increase the maximum amount of RAM, use the Max memory usage parameter.

If user management via SQL is enabled for the cluster, you can set the Max memory usage parameter as follows:

• For the current user session by running this query:

  SET max_memory_usage = <value_in_bytes>;
  

• For all default users by creating a settings profile.

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