Update 04-user-create-role.md

Author: BohuTANG

docs/en/sql-reference/10-sql-commands/00-ddl/02-user/04-user-create-role.md

@@ -6,26 +6,80 @@ import FunctionDescription from '@site/src/components/FunctionDescription';
 
 <FunctionDescription description="Introduced or updated: v1.2.703"/>
 
-Creates a new role.
-
-After creating roles, you can grant object privileges to the role, enable access control security for objects in the system.
-
-See also: [GRANT](10-grant.md)
+Creates a new role for access control. Roles are used to group privileges and can be assigned to users or other roles, providing a flexible way to manage permissions in Databend.
 
 ## Syntax
 
 ```sql
-CREATE ROLE [ IF NOT EXISTS ] <name> [ COMMENT = '<string_literal>' ]
+CREATE ROLE [ IF NOT EXISTS ] <name>
 ```
 
-- The `<name>` cannot contain the following illegal characters:
-    - Single quote (')
-    - Double quote (")
-    - Backspace (\b)
-    - Form feed (\f)
+**Parameters:**
+
+- `IF NOT EXISTS`: Create the role only if it doesn't exist (recommended to avoid errors)
+- `<name>`: Role name (cannot contain single quotes, double quotes, backspace, or form feed characters)
 
 ## Examples
 
 ```sql
-CREATE ROLE role1;
-```
+-- Create a basic role
+CREATE ROLE analyst;
+
+-- Create role only if it doesn't exist (recommended)
+CREATE ROLE IF NOT EXISTS data_viewer;
+```
+
+## Common Usage Patterns
+
+### Read-Only Analyst Role
+
+Create a role for data analysts who need read access to sales data:
+
+```sql
+-- Create the analyst role
+CREATE ROLE sales_analyst;
+
+-- Grant read permissions
+GRANT SELECT ON sales_db.* TO ROLE sales_analyst;
+
+-- Assign to users
+GRANT ROLE sales_analyst TO 'alice';
+GRANT ROLE sales_analyst TO 'bob';
+```
+
+### Database Administrator Role
+
+Create a role for administrators who need full control:
+
+```sql
+-- Create the admin role
+CREATE ROLE sales_admin;
+
+-- Grant full permissions on the database
+GRANT ALL ON sales_db.* TO ROLE sales_admin;
+
+-- Grant user management permissions
+GRANT CREATE USER, CREATE ROLE ON *.* TO ROLE sales_admin;
+
+-- Assign to admin users
+GRANT ROLE sales_admin TO 'admin_user';
+```
+
+### Verification
+
+```sql
+-- Check what each role can do
+SHOW GRANTS FOR ROLE sales_analyst;
+SHOW GRANTS FOR ROLE sales_admin;
+
+-- Check user permissions
+SHOW GRANTS FOR 'alice';
+SHOW GRANTS FOR 'admin_user';
+```
+
+
+## See Also
+
+- [GRANT](10-grant.md) - Grant privileges and roles
+- [SHOW GRANTS](22-show-grants.md) - View granted privileges
+- [DROP ROLE](05-user-drop-role.md) - Drop roles