Since this commit, we fully support GUID as primary keys. It is easy to get back GUID's for existing records as your identity columns. However, you will have to setup a few model callbacks if you want ...

not to worry, you aren’t alone. A GUID is a Globally Unique Identifier that helps manage the relational data in the Common Data Service for Apps and SQL Server. PowerApps is committed to providing an ...

The following table shows the ODBC SQL data types to which GUID C data may be converted. For an explanation of the columns and terms in the table, see Converting Data from C to SQL Data Types.