Queries With GROUP BY and HAVING

• The target-list contains (i) attribute names (ii) terms with aggregate operations (e.g., MIN (S.age)).

  • The attribute list (i) must be a subset of grouping-list. Intuitively, each answer tuple corresponds to a group, and these attributes must have a single value per group. (A group is a set of tuples that have the same value for all attributes in grouping-list.)

SELECT [DISTINCT] target-list

FROM relation-list

WHERE qualification

GROUP BY grouping-list

HAVING group-qualification

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