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  • 力扣sql题

    组合两个表

    表1: Person

    +-------------+---------+
    | 列名 | 类型 |
    +-------------+---------+
    | PersonId | int |
    | FirstName | varchar |
    | LastName | varchar |
    +-------------+---------+
    PersonId 是上表主键
    表2: Address

    +-------------+---------+
    | 列名 | 类型 |
    +-------------+---------+
    | AddressId | int |
    | PersonId | int |
    | City | varchar |
    | State | varchar |
    +-------------+---------+
    AddressId 是上表主键
     

    编写一个 SQL 查询,满足条件:无论 person 是否有地址信息,都需要基于上述两表提供 person 的以下信息:

     建表语句:

    Create table Person (PersonId int, FirstName varchar(255), LastName varchar(255))
    Create table Address (AddressId int, PersonId int, City varchar(255), State varchar(255))
    Truncate table Person
    insert into Person (PersonId, LastName, FirstName) values ('1', 'Wang', 'Allen')
    Truncate table Address
    insert into Address (AddressId, PersonId, City, State) values ('1', '2', 'New York City', 'New York')
    

      解法:

    select FirstName, LastName, City, State
    from Person left join Address
    on Person.PersonId = Address.PersonId
    

      

    FirstName, LastName, City, State

    来源:力扣(LeetCode)
    链接:https://leetcode-cn.com/problems/combine-two-tables
    著作权归领扣网络所有。商业转载请联系官方授权,非商业转载请注明出处。

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  • 原文地址:https://www.cnblogs.com/q1359720840/p/11104559.html
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