system.enabled_roles 

Contains all active roles at the moment, including current role of the current user and granted roles for current role.

Columns:

• role_name (String)) — Role name.
• with_admin_option (UInt8) — Flag that shows whether enabled_role is a role with ADMIN OPTION privilege.
• is_current (UInt8) — Flag that shows whether enabled_role is a current role of a current user.
• is_default (UInt8) — Flag that shows whether enabled_role is a default role.

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