This task concerns the following tables:PersonsidnameaddressageeyeColorgenderWrite a query that returns the name of all persons that are at least as old as everybody else.TipRecall the logic recap: FOR ALL X can be expressed by NOT EXISTS NOT X
Question
This task concerns the following tables:PersonsidnameaddressageeyeColorgenderWrite a query that returns the name of all persons that are at least as old as everybody else.TipRecall the logic recap: FOR ALL X can be expressed by NOT EXISTS NOT X
Solution
To answer your question, you can use a subquery to find the maximum age, and then use this subquery in the WHERE clause of your main query. Here is the SQL query:
SELECT name
FROM Persons
WHERE age >= (SELECT MAX(age) FROM Persons);
This query works as follows:
- The subquery
(SELECT MAX(age) FROM Persons)finds the maximum age of all persons in the table. - The main query then selects the names of all persons whose age is greater than or equal to this maximum age.
This will return the names of the oldest persons in the table.
Similar Questions
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