Hi all!
I'm completely new to Power BI. I work for an education company and the data I am compiling is from multiple data dumps, which have student IDs and demographic info in one csv file, questions they have received in another csv, and responses to those questions in a third csv.
I was using excel to answer three basic queries for subsets of students:
1. What questions did (each) student receive?
2. What questions did (each) student answer?
3. What did students answer?
(Two additional queries are when did they receive the questions, and when did they answer).
The first and second queries need to be calculated (not all students receive all questions, and not all students answer all questions they receive) so I calculated a received column with 0/1 values and an answered column with the same, for each question. Here's an example formula, where I named the column with the question ID:
=COUNTIFS(QTR!$B:$B,$A2,QTR!$C:$C,RIGHT(AV$1,3))
For each question received column, I just copied across the formula. I did the same for each question answered.
For the overall data set, there are approximately 500 questions, so I would need to do this for 1000 columns. It's too much calculation for excel, in addition to the vlookups for what the students answered, and when they received and answered the questions. So I started to investigate Power BI to do this. From what I've been able to learn so far, I don't need to flatten the data for query 3 (what they answered) or for when they received/answered a question, since that data is explicitly in the csv files. But I'm stuck on queries 1 and 2.
Any tips for how to go about this? I'm quessing creating 1000 calculated columns is not the best way to go?
Thanks!!
Betsy