題目:
DELETE 相同的Email,留下小的Id。
Write a SQL query to delete all duplicate email entries in a table named Person, keeping only unique emails based on its smallest Id.
Person
列出各Department 中Salary 前三高的名單。
The Employee table holds all employees. Every employee has an Id, and there is also a column for the department Id.
Employee
給定一組數字,為這組數字加1,例如底下[1,2,3] 變成 [1,2,4]
Input: digits = [1,2,3]Output: [1,2,4]Explanation: The array represents the integer 123.
思路: