It is possible to integrate the Tableau client application to run query for reporting purpose.
When trying to connect from Tableau to your instance, the following error is shown "You are not authorized to access this resource. Check with your ServiceNow administrator to verify that the access control lists have the correct permissions set."
Out of the box ACLs created be default for a new user in Servicenow are not sufficient to allow Tableau to connect
As per the Tableau docs, the following permissions are required
For ServiceNow administrators
ServiceNow uses access control lists (ACLs) to specify who has access to which data. Often the default permissions that are set for ServiceNow fulfillers are adequate for Tableau users to access the content they need to analyse ServiceNow ITSM data.
Tableau users need to access metadata about tables in ServiceNow, which is available in the following tables:
sys_dictionary table (metadata about columns)
sys_db_object table (metadata about tables)
sys_glide_object table (metadata about field types)
If a Tableau user can't access ServiceNow ITSM data, make sure that the ACLs provide the user table level and field level read access to the tables above, and that there are no scripts that are locking down access.
To grant access to the metadata tables, as a best practice, you might consider creating a role with the ACLs needed to access the metadata tables, and then assign the role to a Tableau User group. Then, you can assign Tableau users to the group so that users can access the data needed for analysis in Tableau.
For information on the creation of an ACL, please see the ServiceNow Access control list rules on the ServiceNow website.