Create a database (see Creating a Database to Contain the Repository and a service to run the database (see Running the Database as a Service) using one of the supported DBMSs:
SAP® SQL Anywhere® v16, 17 (bundled with PowerDesigner, see Installing and Authenticating SQL Anywhere)
SAP® Adaptive Server® Enterprise v15.7, 16.x
SAP HANA® v1.0, 2.0
Oracle 11g, 12c
IBM DB2 LUW v10.5
DB2 z/OS 11.x, 12
Microsoft SQL Server 2012, 2014, 2016 - we recommend that you use a server that is not currently managing a high transaction load, since PowerDesigner performs long-running synchronous transactions during Check-In/Check-Out.