Merge pull request ClickHouse#1561 from ClickHouse/rbac-kb-article

KB article: Common RBAC queries for ClickHouse Cloud

knowledgebase/common-rbac-queries.md

@@ -0,0 +1,35 @@
+---
+title: Common RBAC queries
+description: "Queries to help grant specific permissions to users."
+date: 2023-09-28
+---
+
+# Common role-based access control (RBAC) queries
+
+## How do I grant the same permissions as the current user to another user?
+
+```sql
+GRANT CURRENT GRANTS ON *.* TO another_user;
+```
+
+## How do I grant a specific permission to a user based on the grants of the current user?
+
+In the below example, `another_user` will be able to perform `SELECT` commands on all of the databases and tables of the current user.
+
+```sql
+GRANT CURRENT GRANTS(SELECT ON *.*) TO another_user;
+```
+
+## How do I grant a specific permission to a user for a specific database based on the grants of the current user?
+
+In the below example, `another_user` will be able to perform `INSERT` commands to all tables in `my_database`.
+
+```sql
+GRANT INSERT ON my_database.* TO another_user;
+```
+
+## How do I give access to all grants for a specific user based on the default user?
+
+```sql
+GRANT default_role TO another_user;
+```