Clickhouse connection is not working

[evgeny-barinov]

When I try to set up a connection to Clickhouse, which is by desing readonly the extension displays the error: Cannot modify 'readonly' setting in readonly mode..

Looks like it tries to set up readonly flag for current session but it is not allowed for my credentials.

[mikeburgh]

Fixed in 1.17.32 which has just been released.. It will only try and set read-only now if you configure it in the connection.

[evgeny-barinov]

@mikeburgh
Hi! Thank you for such a quick fix. It seems the fix or something else caused the new issue:

Not enough privileges. To execute this query, it's necessary to have the grant SELECT(bytes_on_disk, database) ON system.parts.

[mikeburgh]

No worries, do you have access to system.tables ? it's going to be a bit tricky to figure out what is going to work pending on what you have access to..

[evgeny-barinov]

I don't have access to any objects in system.* . Just the database I configured in the connection settings.

[mikeburgh]

hmm, all the introspection code at the moment uses system to get the information about tables, columns, etc.

Can you run these commands and get data back from them ?

SHOW DATABASES;
SHOW TABLES;
DESCRIBE TABLE (any_table_name);

[evgeny-barinov]

@mikeburgh

• SHOW DATABASES; - displays the only one database I have access to. Works fine
• SHOW TABLES; - displays tables list in the database I configured in the connection settings. Same database is displayed by SHOW DATABASES;
• DESCRIBE TABLE (any_table_name); - displays the table's fields list. Works fine.

Looks like the extensions tries to read size of database or tables from system.parts to display it like on the example below. It's may better to ignore it if there is no such a permission.

[evgeny-barinov]

This issue should be related to it as well #793 .