Write a SQL query to find all duplicate emails in a table named Person. +----+---------+ | Id | Email | +----+---------+ | 1 | a@b.com | | 2 | c@d.com | | 3 | a@b.com | +----+---------+ For example, your query should return the following for the abov…

Write a SQL query to delete all duplicate email entries in a table named Person, keeping only unique emails based on its smallest Id. +----+------------------+ | Id | Email | +----+------------------+ | 1 | john@example.com | | 2 | bob@example.com |…

https://leetcode.com/problems/duplicate-emails/description/ 首先sql的执行顺序是 from-->where-->group by--->having-->select-->order by 所以用了group后,用where判断是错误的 # Write your MySQL query statement below select distinct Email //这里不需要distinct,因为group后,相同…

Write a SQL query to find all duplicate emails in a table named Person. +----+---------+ | Id | Email | +----+---------+ | 1 | a@b.com | | 2 | c@d.com | | 3 | a@b.com | +----+---------+ For example, your query should return the following for the abov…

Given a Weather table, write a SQL query to find all dates' Ids with higher temperature compared to its previous (yesterday's) dates. +---------+------------------+------------------+ | Id(INT) | RecordDate(DATE) | Temperature(INT) | +---------+-----…

There is a table World +-----------------+------------+------------+--------------+---------------+ | name | continent | area | population | gdp | +-----------------+------------+------------+--------------+---------------+ | Afghanistan | Asia | 652…

题目标签: 题目给了我们一个 email 的table,让我们找到重复的 email. 可以建立 Person a, Person b, 找到两个表格中,emai 相等 但是 id 不同的 email, 然后利用DISTINCT 返回,因为两个表格中,会找到两个 重复的email. Java Solution: Runtime:  224 ms, faster than 40 % Memory Usage: N/A 完成日期:06/01/2019 关键点:用DISTINCT # Write yo…

A pupil Tim gets homework to identify whether three line segments could possibly form a triangle. However, this assignment is very heavy because there are hundreds of records to calculate. Could you help Tim by writing a query to judge whether these…

Description Given three tables: salesperson, company, orders.Output all the names in the table salesperson, who didn’t have sales to company 'RED'. ExampleInput Table: salesperson +----------+------+--------+-----------------+-----------+ | sales_id…

Select all employee's name and bonus whose bonus is < 1000. Table:Employee +-------+--------+-----------+--------+ | empId | name | supervisor| salary | +-------+--------+-----------+--------+ | 1 | John | 3 | 1000 | | 2 | Dan | 3 | 2000 | | 3 | Brad…