Done SQL 1

Problem1.sql

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+SELECT name, population, area
+FROM World
+WHERE area >= 3000000 OR population >= 25000000

Problem2.sql

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+CREATE FUNCTION getNthHighestSalary(N INT) RETURNS INT
+BEGIN
+
+DECLARE M INT;
+ SET M = N-1;
+
+   RETURN (
+       # Write your MySQL query statement below.
+       SELECT DISTINCT salary 
+       FROM Employee
+       ORDER BY salary DESC
+       LIMIT M, 1
+   );
+END

Problem3.sql

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+DELETE p1 FROM Person p1
+JOIN Person p2
+WHERE p1.id > p2.id AND p1.email = p2.email