LeetCode 183. Customers_Who_Never_Order

Tutd Schema:

customers := relation{tuple{id 1, name "Joe"}, tuple{id 2, name "Henry"}, tuple{id 3, name "Sam"}, tuple{id 4, name "Max"}};
orders := relation{tuple{id 1, customerId 3}, tuple{id 2, customerId 1}};

key customers_pkey {id} customers;
key orders_pkey {id} orders;

Thinking Process:

TutorialD (master/main): :importtutd "183__Customers_Who_Never_Order.tutd"

TutorialD (master/main): :showexpr (customers not matching (orders{customerId} rename {customerId as id})){name}
┌──────────┐
│name::Text│
├──────────┤
│"Max"     │
│"Henry"   │
└──────────┘

What a one-liner! How nice!

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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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