First create a query of membership transactions:
  1. Go to Analysis > Information Library.  Click Add an ad-hoc query.  Select the source view of Revenue and click Ok.
  2. On the left, click Application Details.  IN the middle, click Application and move to Include Records Where.  Set equal to Membership.
  3. Go to the Set Save Options tab.  Name the query.
  4. Mark the box to create a selection and mark the box to show this selection in query designer.
  5. Click Save and close.
Next, create a query of donation transactions that also have membership transactions in the same transaction: 
  1. Go to Analysis > Information Library.  Click Add an ad-hoc query.  Select the source view of Revenue and click Ok.
  2. On the left, click Application Details.  In the middle, click Application Details and move to Include Records Where.  Set equal to Donation.
  3. On the left, click Selections.
  4. In the middle, select your Membership Transactions query from step 1.  
  5. Move this to Include Records Where.  Set the criteria to equal to Yes.
  6. Go to the Set Save Options tab.
  7. Mark the box to create a selection and mark the box to show this selection in query designer.
  8. Click Save and Close.
Last, edit your acknowledgement donation query to exclude your membership and donation query.
  1. Go to Analysis > Information Library.  Locate the donation revenue query used in your Acknowledgement donation letter.
  2. On the left, click Selections.
  3. In the middle, select your selection from Step 2.
  4. Move this to Include Records Where.  Set the criteria to Equal to no.
  5. Save and close your query.