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Table:Failed+--------------+---------+| Column Name | Type |+--------------+---------+| fail_date | date |+--------------+---------+Primary key for this table is fail_date.Failed table contains the days of failed tasks.Table:Succeed..

Table:Logs+---------------+---------+| Column Name | Type |+---------------+---------+| log_id | int |+---------------+---------+id is the primary key for this table.Each row of this table contains the ID in a log Table.Sinc...

Table:Customer+---------------+---------+| Column Name | Type |+---------------+---------+| customer_id | int || name | varchar || visited_on | date || amount | int |+---------------+---------+(customer_id, .

Table:Points+---------------+---------+| Column Name | Type |+---------------+---------+| id | int || x_value | int || y_value | int |+---------------+---------+id is the primary key for this table.Each p.

TablePerson:+----------------+---------+| Column Name | Type |+----------------+---------+| id | int || name | varchar || phone_number | varchar |+----------------+---------+id is the primary key for this table..

Table:Patients+--------------+---------+| Column Name | Type |+--------------+---------+| patient_id | int || patient_name | varchar || conditions | varchar |+--------------+---------+patient_id is the primary key for this table.'co.

Table:Sales+--------------+---------+| Column Name | Type |+--------------+---------+| sale_id | int || product_name | varchar || sale_date | date |+--------------+---------+sale_id is the primary key for this table.Each row .

Table:Traffic+---------------+---------+| Column Name | Type |+---------------+---------+| user_id | int || activity | enum || activity_date | date |+---------------+---------+There is no primary key for this table, it .

Table:Sessions+---------------------+---------+| Column Name | Type |+---------------------+---------+| session_id | int || duration | int |+---------------------+---------+session_id is the primary key for .

Table:Queue+-------------+---------+| Column Name | Type |+-------------+---------+| person_id | int || person_name | varchar || weight | int || turn | int |+-------------+---------+person_id is the primary key colu.

Table:Users+----------------+---------+| Column Name | Type |+----------------+---------+| user_id | int || join_date | date || favorite_brand | varchar |+----------------+---------+user_id is the primary key of this tab.

Table:Products+---------------+---------+| Column Name | Type |+---------------+---------+| product_id | int || new_price | int || change_date | date |+---------------+---------+(product_id, change_date) is the primary k.

Table:Delivery+-----------------------------+---------+| Column Name | Type |+-----------------------------+---------+| delivery_id | int || customer_id | int || order_date .

Table:ActorDirector+-------------+---------+| Column Name | Type |+-------------+---------+| actor_id | int || director_id | int || timestamp | int |+-------------+---------+timestamp is the primary key column for this table..

Table:Activity+--------------+---------+| Column Name | Type |+--------------+---------+| player_id | int || device_id | int || event_date | date || games_played | int |+--------------+---------+(player_id, event_date.

Table:Product+--------------+---------+| Column Name | Type |+--------------+---------+| product_id | int || product_name | varchar || unit_price | int |+--------------+---------+product_id is the primary key of this table.Tab.

Table:Players+-------------+-------+| Column Name | Type |+-------------+-------+| player_id | int || group_id | int |+-------------+-------+player_id is the primary key of this table.Each row of this table indicates the group of each .

Table:Movies+---------------+---------+| Column Name | Type |+---------------+---------+| movie_id | int || title | varchar |+---------------+---------+movie_id is the primary key for this table.title is the name of the mov.

Table:Orders+---------------+---------+| Column Name | Type |+---------------+---------+| order_id | int || customer_id | int || order_date | date | | item_id | varchar || quantity | int |+--------------.

Table:Sales+---------------+---------+| Column Name | Type |+---------------+---------+| sale_date | date || fruit | enum | | sold_num | int | +---------------+---------+(sale_date,fruit) is the primary key for th.

MySql 里的IFNULL、NULLIF和ISNULL用法MySQL 日期与时间方面的函数

TableAccounts:+---------------+---------+| Column Name | Type |+---------------+---------+| id | int || name | varchar |+---------------+---------+the id is the primary key for this table.This table contains the acco.

Table:Spending+-------------+---------+| Column Name | Type |+-------------+---------+| user_id | int || spend_date | date || platform | enum | | amount | int |+-------------+---------+The table logs the spendings .

TheEmployeetable holds all employees. The employee table has three columns: Employee Id, Company Name, and Salary.+-----+------------+--------+|Id | Company | Salary |+-----+------------+--------+|1 | A | 2341 ||2 | A ..

Table:Product+---------------+---------+| Column Name | Type |+---------------+---------+| product_id | int || product_name | varchar |+---------------+---------+product_id is the primary key for this table.product_name is the name .

Table:Actions+---------------+---------+| Column Name | Type |+---------------+---------+| user_id | int || post_id | int || action_date | date || action | enum || extra | varchar |+--------------.

Given two tables as below, write a query to display the comparison result (higher/lower/same) of the average salary of employees in a department to the company's average salary.Table:salary| id | employee_id | amount | pay_date ||----|------------.

Table:Visits+---------------+---------+| Column Name | Type |+---------------+---------+| user_id | int || visit_date | date |+---------------+---------+(user_id, visit_date) is the primary key for this table.Each row of thi.

+----------------+---------+| Column Name | Type |+----------------+---------+| book_id | int || name | varchar || available_from | date |+----------------+---------+book_id is the primary key of this table.Table:O..

+---------------+---------+| Column Name | Type |+---------------+---------+| employee_id | int || employee_name | varchar || manager_id | int |+---------------+---------+employee_id is the primary key for this table.Each row of .

Write a SQL query to find all numbers that appear at least three times consecutively.+----+-----+| Id | Num |+----+-----+| 1 | 1 || 2 | 1 || 3 | 1 || 4 | 2 || 5 | 1 || 6 | 2 || 7 | 2 |+----+-----+For example, given the

TheEmployeetable holds all employees. Every employee has an Id, and there is also a column for the department Id.+----+-------+--------+--------------+| Id | Name | Salary | DepartmentId |+----+-------+--------+--------------+| 1 | Joe | 85000 ..

Write a SQL query to rank scores. If there is a tie between two scores, both should have the same ranking. Note that after a tie, the next ranking number should be the next consecutive integer value. In other words, there should be no "holes" between ranks

https://www.cnblogs.com/52xf/p/4209211.htmlCREATE TABLE [dbo].[Order]( [ID] [int] IDENTITY(1,1) NOT NULL, [UserId] [int] NOT NULL, [TotalPrice] [int] NOT NULL, [SubTime] [datetime] NOT NULL, CONSTRAINT [PK_Order] PRIMARY KEY CLUSTERED

Write a SQL query to get thenthhighest salary from theEmployeetable.+----+--------+| Id | Salary |+----+--------+| 1 | 100 || 2 | 200 || 3 | 300 |+----+--------+For example, given the above Employee table, thenthhighest salary...

+---------------+---------+| Column Name | Type |+---------------+---------+| id | int || revenue | int || month | varchar |+---------------+---------+(id, month) is the primary key of this table.The table has.

The Employee table holds all employees including their managers. Every employee has an Id, and there is also a column for the manager Id.+------+----------+-----------+----------+|Id |Name |Dep...

Mary is a teacher in a middle school and she has a table seat storing students' names and their corresponding seat ids.The column id is continuous increment.Mary wants to change seats for the adjacent...

Round() and isnull, round() can be used directly.In social network like Facebook or Twitter, people send friend requests and accept others’ requests as well. Now given two tables as below:Table:frie...

max，min函数with group by是针对每组的数据求最大最小值Approach: Using DELETE and WHERE clauseWrite a SQL query to delete all duplicate email entries in a table named Person, keeping only unique emails based on its smal...