What would a sample query look like using the above data set?

 

Dataset: sample_dx.csv When patient gets a diagnosis from physician, a diagnosis code will be provided to identify what disease, disorders, symptoms or other reasons for patient encounters. We want to define a patient cohort for certain theraputical area based on the diagnosis they get. The 3 groups of interested diagnosis code are: Group A: C83.0, C83.00, C83.01, C83.02, C83.03 Group B: C91, C91.1, C91.10, C91.11, C91.12 Group C: C95.10, C95.90 A patient must have at least one diagnosis from the 3 groups above to be included in the paitent cohort. It's relatively rare to get two different groups of diagnosis within one month, how many patients have diagnosis codes from two different groups within the same month? (Let's use calendar month here.)