In addition to the attributes offered by the Student Datawarehouse in each of its objects, you can add your own custom-built attributes based on the attributes already available. You can save these "computed attributes" so you can use them for future queries. When you create an attribute it will be available to you but not to other users.

In this example, let's say you want to create a computed attribute that will calculate a GPA based on selected courses (say, all undergraduate courses with a 'PS' subject code). Your plan for calculating the gpa is to use this fraction:

1. Go to the All Terms(1) model.
2. Open the Transcript(1) object.
3. Now you need to decide where you want your new attribute to appear on the attribute list. Once you've decided, pick the attribute immediately above where you want the new attribute to appear and using its function box select the 'calculation...' function. (After you have finished defining your new attribute, its name will appear directly beneath the attribute you have selected).
4. You should now see the Edit Calculation window. Notice the Expression box. This is where you build and edit your computed attribute. Click once in the box to begin (you should get a blinking cursor in the box). You can build an expression by a combination of typing, inserting attributes, inserting functions, and/or using the keypad buttons.

   Start by building the numerator (see our formula above). Select the Grade Points attribute from the scrolling Table/Attributes window by clicking on it once. Press the Insert Function button and select SUM from the list on the left. Press the Insert button. (We could type in the attribute and function names instead of inserting them, but it's much easier to just pick from a list and press insert).

   The expression

   (SUM(DATAMGR.DWS_TRANSCRIPT_ENRLSTD_VIEW.GRADE_POINTS)) should now appear in the expression box. That's the numerator. If it doesn't look right, just delete everything in the Edit Calculation window and do step 4 over again.
5. Now you need to put in the division operator. In the expression box move the cursor between the last two parentheses and press the '/' button.

   The expression should now look like this:

   (SUM(DATAMGR.DWS_TRANSCRIPT_ENRLSTD_VIEW.GRADE_POINTS)/)
6. Now for the denominator. Make sure the cursor is blinking right after the "/" you just inserted. Select the GPA Hours attribute from the scrolling Table/Attributes window by clicking on it once. Press the Insert Function button and select SUM from the list on the left. Press the Insert button.
7. Your new attribute has been defined. The expression should now look like this: (SUM(DATAMGR.DWS_TRANSCRIPT_ENRLSTD_VIEW.GRADE_POINTS) / SUM(DATAMGR.DWS_TRANSCRIPT_ENRLSTD_VIEW.GPA_HOURS)) If you've made a mistake, edit the expression in the Edit Calculation window until it looks exactly like the expression above.
8. Type in a name for your new attribute in the Name: field (e.g.,'Grouped GPA'). Press the OK button and your new attribute will appear on the attribute list.

How do you use your new attribute? Let's say you want to produce a report of all current political science majors including their names, ids, and GPAs based just on their political science courses.

Here's how you do it:

1. Go to the All Terms(1) model.
2. Select New Query from the Query menu.
3. Open the Person(1) object.
4. Select STUDENT ID and click its group box.
5. Select LFM Name.
6. Close the Person(2) window and open the Transcripts(1) object.
7. Select the new Grouped GPA attribute.
8. Qualify Count in GPA Flag = Y
9. Qualify SUBJECT CODE = PS
10. Qualify GPA Hours > 0 (GPA Hours is in the denominator and we can't divide by zero).
11. You want only UO courses to be counted in the GPA, so qualify Inst Transfer Flag = I.
12. Qualify Course Level = UG (just undergrad courses).
13. Close the Transcript(1) window and open the Current Students object.
14. Qualify Hours Registered > 0.
15. Qualify All Majors contains |PS|.
16. Qualify Level Code = UG (just undergrad students).
17. Run the query.

Note that you grouped on ID because you wanted a separate GPA for each student. You also made sure that the course counted in the GPA and that only PS courses were used in the calculation. And you made sure that GQL wouldn't have to divide by zero. You qualified on Course Level because GPAs should always be calculated by level. And finally, you used the Current Student object to only bring back GPAs for currently enrolled political science majors.

By changing the selection, you can calculate a GPA on other groups of courses making this a very handy attribute! The above query took about 30 minutes to execute.