Tutorial Chapter 6: Add, Update and Delete

Parent topic: Tutorial Chapter 6: Add, Update and Delete

Deleting a Row

The SQL DELETE statement can be used to delete rows from the database table. The primary key of the row to be deleted can be obtained from the values in the program record.

Using a dialog Menu to prompt for validation
The MENU statement has an optional STYLE attribute that can be set to 'dialog', automatically opening a temporary modal window. You can also define a message and icon with the COMMENT and IMAGE attributes. This provides a simple way to prompt the user to confirm some action or operation that has been selected.
Example: Deleting a Row
Function delete_check is added to the custquery.4gl module to check whether a store has any orders in the database before allowing the user to delete the store from the customer table. If there are no existing orders, a dialog MENU is used to prompt the user for confirmation.

Parent topic: Tutorial Chapter 6: Add, Update and Delete