LeetCode 196. Delete Duplicate Emails

Tutd Schema:

person :: {id Integer, email Text};
person := relation{tuple{id 1, email "join@example.com"},
                  tuple{id 2, email "bob@example.com"},
                  tuple{id 3, email "join@example.com"}};

Thinking Process:

TutorialD (master/main): person := ((person group ({all but email} as ids):{minId := min(@ids)}){all but ids}) rename {minId as id}
TutorialD (master/main): :showexpr person
┌──────────────────┬───────────┐
│email::Text       │id::Integer│
├──────────────────┼───────────┤
│"bob@example.com" │2          │
│"join@example.com"│1          │
└──────────────────┴───────────┘


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LeetCode 184. Department Highest Salary

Tutd Schema: employee :: {id Integer, name Text, salary Integer, departmentId Integer}; employee := relation{tuple{id 1, name "Joe", salary 70000, departmentId 1},                     tuple{id 2, name "Jim", salary 90000, departmentId 1},                     tuple{id 3, name "Henry", salary 80000, departmentId 2},                     tuple{id 4, name "Sam", salary 60000, departmentId 2},                     tuple{id 5, name "Max", salary 90000, departmentId 1}}; key employee_pkey {id} employee; department :: {id Integer, name Text}; department := relation{tuple{id 1, name "IT"}, tuple{id 2, name "Sales"}} key department_pkey {id} department; Thinking Process: TutorialD (master/main): grouped := employee group ({all but departmentId} as byDepartment)  TutorialD (master/main): :showexpr grouped ┌───────────────────────────────────────────────────────────────┬─────────────────────┐                                 
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