Assume that a single-row form is created on the Member table and you are using it to enter data in the table. State the steps you would take to create a trigger that will fire and insert the next card number in the member record when the record is saved. Specify the type of trigger you will use and write the trigger code. Assume that a sequence generator already exists.

Question

What will be an ideal response?

Answer 1

- Double-click ‘cardNo’ field in Object Navigator. In the Property Palette window
that opens change the property ‘Required’ under the Data section to ‘No’;
- Drag the field icon, in the Object navigator, to the end of the attributes list;
- Right click the table block icon in Object Navigator;
- Select ‘PL/SQL’ Editor and choose PRE-INSERT trigger from the window that
opens and click OK.
- In the window that opens (PL/SQL Editor window) type the following code:
SELECT Member_Seq.NEXVAL
INTO :Member.cardNo
FROM SYS.dual;