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Now that the NeXTensio list and form are built, let's observe their browser behavior by using them to add, edit or delete students and the courses they registered to.
First, let's see the records in the student_std and student_to_course_stc tables before performing any changes (if you used the sql or mdb script provided in the zip package to create the database).
The initial state of the student_std table:
The initial state of the student_to_course_stc
table:
Open the index page and preview it in the
browser. The name and e-mail address of the students are displayed. Let's
add 3 new students along with the courses they register to:
After clicking the add new button, the
NeXTensio form will be displayed:
Click the Insert button for the 3 set of records to be inserted (do not forget to type valid e-mail addresses since you chose to use a validation rule for this form field). The insertion operation will affect the student_std table (3 new records) and the student_to_course_stc table (3x3=9 new records). See below how the student_std and student_to_course_stc tables look after the insertion.
The student_std table after the insertion:
The student_to_course_stc table after the
insertion:
If you want to change the courses one (or more) student registered to,
simply click the edit button in the NeXTensio list and then check and/or uncheck courses
as desired:
Check for yourself and see how the records in the student_to_course_stc table are updated: the rows corresponding to the unchecked courses will be deleted, and new rows will be added corresponding to the new courses that you check.
If you delete a student using the NeXTensio list, in the student_to_course_stc table all the records that associated that student to the courses he/she attended will be deleted. Evidently, that student will be deleted from the student_std table.
By using the Many-To-Many Wizard, manipulating many-to-many related tables becomes as simple as it could be.