Scenario: Restrict IAM users whose usernames are prefixed with sso- from accessing cloud resolution DNS services.
Policy example:

{ 
  "Statement": [ 
    { 
      "Effect": "Allow", 
      "Action": [ 
        "dns:*" 
      ], 
      "Resource": [ 
        "*" 
      ], 
      "Condition":{ 
          "StringLike":{ 
                  "volc:UserName":"sso-*" 
          } 
      } 
    } 
  ] 
}

For details of the condition key, please refer to the Condition Use Instructions