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General form of Grouping and Aggregation
•SELECT S
FROM R1,…,Rn
WHERE
C1
•GROUP
BY a1,…,ak
HAVING C2
S = may contain
attributes a1,…,ak and/or any
aggregates but NO OTHER ATTRIBUTES
C1 = is any condition on the
attributes in R1,…,Rn
C2 = is any condition on
aggregate expressions
Why ?