Using ASF › The Structure and Functions of ASF › Data Access

Data Access

When you generate a table through ASF, an application program that allows you to use the table online can be generated automatically. The application allows you to display, add, modify, and delete rows in the stored table and display and modify rows in a view. As part of the application, a Data Display screen is formatted for the table, displaying the columns defined for the table and providing response fields for adding and displaying rows of the table. Though not actually an ASF screen, the Data Display screen for a particular table can be accessed directly from ASF in the following ways:

Selecting Data to View: Through the Data Selection (DSEL) screen—ASF provides a run-time selection screen similar to the Extended Selection Definition screen described earlier. The Data Selection screen allows you to specify a value or range of values for one or more columns in the table. Only the rows whose columns match the values specified will be displayed on the Data Display screen.

When you have specified the rows to be selected, the Data Selection screen transfers control directly to the Data Display screen, which displays the first row that matches the selection conditions specified.

The selection criteria do not affect what data is stored in the table, only what data is displayed in this run of the ASF-created application.

Adding Data : Through the Load Data (DLOD) function—The Data Display screen displays the column headings so you can enter new data online, one row at a time, and add the new data to the database.

Row by Row Changes : Through the Display/Change Data (DDIS) function—The Data Display screen lists the column headings and one row of data and allows you to:

• Modify the table in the database by changing, adding, or deleting data
• Display the entire table, one row at a time

When you access the Data Display screen, you are using the application developed by ASF for the data table. After completing all data access transactions (displaying, adding, changing, and deleting rows) through the table's online application, you return to ASF to continue or to conclude the ASF session.