This option eliminates the use of external lists and web services, since the Query XQL action uses ERPConnect Services for a direct integration with SAP.

XQL (Extract Query Language) is a query language for SAP integration and a part of ERPConnect Services. By specifying an XQL statement SAP objects including tables, function modules, queries or cubes can be queried using an SQL-like syntax.

Nintex Workflow and Query XQL Action