To edit a record displayed on the top page, the record is selected by clicking one of its display fields. Each field has the same set of actions defined for it (see screenshot below), which is essentially to go to the Edit Book sub page. You can follow this by looking up the actions of one or more of these fields.
The selected book will be displayed in the editing template of the Edit Book sub page (shown below in a simulator).
Note the following points:
•The page source of the Edit Book sub page is $EDIT-BOOK, which filters the records of the DB to show only the selected book.
•The page source contains an OriginalRowSet node to hold the original data while RowSet holds the data being edited. In the screenshot above, the Publisher field has been edited from "Signet" to "Signet Classics". Compare the Publisher fields of OriginalRowSet and RowSet.
•If the Save button is clicked, the data from RowSet is saved to the DB. See the actions of the Save button.
•If the Discard button is clicked, the data from RowSet is discarded. See the actions of the Discard button.
•How images are handled is described in the section Images in the DB.