A non-donor in Salsa CRM would be, by definition, constituents who have a gift count of 0 (zero) and also have never been a co-donor on someone else's gift. There are three steps to get this information:

Identify the constituents with a zero donation count, and add them to a Group.
Identify the co-donors, and add them to a second Group.
Identify those constituents who are in the first Group and not in the second Group.

Step 1: Zero Donation Count

Start a new, general-purpose query based on the Constituent table. The output fields listed below should be the absolute minimum fields to output for your query. The filter fields listed below are the filters necessary to return our non-donors.

NOTE: Added output fields or filter fields may change the query results in unanticipated ways so be careful.
Add the following to this new query:

Output Fields	Filter Fields	Sort Fields
Constituent Constituent Number Donation Info Gift Count	Donation Info Gift Count equals "0"	N/A

In Step 4 of the Query Wizard, click Global Update.
Click Create Smart Group.
Create the Zero Gift Count Smart Group.
Click OK.
Save this Query Criteria.

Step 2: Co-Donors

To add anyone who was a co-donor on someone else's gift to a Co-Donors Smart Group...

Start with the Built-in Query called All Co-Donors.
In Step 4 of the Query Wizard, click Global Update.
Click Create Smart Group.
Create the Co-Donors Smart Group.
Click OK.
Save this Query Criteria.

Step 3: Non-Donors

To query on anyone in the Non-Donors Group who is not in the Co-Donors Group, start a new, mail merge query based on the Constituent table.

Output Fields	Filter Fields	Sort Fields
Output Fields are automatically selected for this type of query	Addresses Primary? equals "Yes" and Constituent Preferred Contact Method does not equal "Do not contact" and Constituent Deceased Date is blank and Groups Group ID equals "Zero Gift Count" and Groups Group ID does not equal "Co-Donors"	Constituent Constituent Type descending Constituent Last or Org Name ascending Constituent First Name ascending Constituent Constituent Number ascending

In Step 4 of the Query Wizard, Save this Query Criteria. Optionally, you can add a Non-Donors Group at this point as well.

In Step 4 of the Query Wizard, click Global Update.
Click Create Smart Group.
Create the Non-Donors Smart Group.
Click OK.