Tutorial Chapter 11: Master/Detail
The form used by the program in this chapter contains fields from
both the orders and items tables in the custdemo
database, illustrating a master-detail relationship. Since there are multiple items associated with
a single order, the rows from the items table are displayed in a table on the form.
This chapter focuses on the master/detail form and the unique features of the corresponding
program.
The Master-Detail sample orders and items tables in the custdemo database.The Makefile Execute or Build options. If you prefer command line tools you can compile and link using a Makefile . This file is interpreted by the make utility, which is a well-known tool to build large programs based on multiple sources and forms.The Customer List Module custlist.4gl module defines a 'zoom' module, to let the user select a customer from a list. The module could be reused for any application that requires the user to select a customer from a list.The Stock List Module stocklist.4gl module defines a 'zoom' module, to let the user select a stock item from a list. This module uses the stocklist.per form and is typical list handling using the DISPLAY ARRAY statement, as discussed in Chapter 07.The Master-Detail Form Specification File orderform.per defines a form for the orders program, and displays fields containing the values of a single order from the orders table. The name of the store is retrieved from the customer table, using the column store_num, and displayed. A screen array displays the associated rows from the items table.The Orders Program orders.4gl orders table would be the same as the examples in Chapter 4 and Chapter 6. Only append and query are included in this program, for simplicity. The add/delete/update of the items table is similar to that in Chapter 8. The complete orders program is outlined, with examples of any new functionality.