Whenever I sort a screen (Customers, Transactions, Suppliers, etc) by clicking on one of the column heading (eg BY ANALYSIS1) an implicit BY PRIMARY-KEY is added. As it is neigh on impossible to change the account code (primary-key) given to Customers or Suppliers, it is more useful to be able to use the Name field to sort the customers (or suppliers) as this can be changed:
BY NAME (click on Name), then
BY ANALYSIS1 (click on Analysis1)
to get the overall effect of
BY ANALYSYS1 BY NAME
except with the implicit BY PRIMARY-KEY the sorts become:
BY NAME BY CUSTOMER_ACCOUNT (click on Name), then
BY ANALYSIS1 BY CUSTOMER_ACCOUNT (click on Analysis1)
to get the overall effect of:
BY ANALYSIS1 BY CUSTOMER_ACCOUNT
ie the pre-sorting BY NAME is destroyed (unlike, for example, in a spreadsheet where the subsequent sort starts with the current state).
This is the same for all the screens which can be sorted by clicking on a column headers (and extends to including Sage Payroll where the primary key is the employee reference)