如何更新MySQL数据库中的两列？
您可以使用用逗号(,)分隔的SET命令更新两列。语法如下-
UPDATE yourTableName SET yourColumnName1 = ’yourValue1’, yourColumnName2 = ’yourValue2’ where yourCondition;
为了理解上述语法，让我们创建一个表。创建表的查询如下-
create table StudentInformations -> ( -> StudentId int not null auto_increment, -> StudentFirstName varchar(20), -> StudentLastName varchar(20), -> Primary Key(StudentId) -> );
使用insert命令在表中插入一些记录。查询如下-
insert into StudentInformations(StudentFirstName,StudentLastName)
values('John','Smith');
insert into StudentInformations(StudentFirstName,StudentLastName)
values('Carol','Taylor');
insert into StudentInformations(StudentFirstName,StudentLastName)
values('Mike','Jones');
insert into StudentInformations(StudentFirstName,StudentLastName)
values('Sam','Williams');
insert into StudentInformations(StudentFirstName,StudentLastName)
values('Bob','Davis');
insert into StudentInformations(StudentFirstName,StudentLastName)
values('David','Miller');使用select语句显示表中的所有记录。查询如下-
select *from StudentInformations;
以下是输出。
+-----------+------------------+-----------------+ | StudentId | StudentFirstName | StudentLastName | +-----------+------------------+-----------------+ | 1 | John | Smith | | 2 | Carol | Taylor | | 3 | Mike | Jones | | 4 | Sam | Williams | | 5 | Bob | Davis | | 6 | David | Miller | +-----------+------------------+-----------------+ 6 rows in set (0.00 sec)
这是更新MySQL数据库中两列的查询。我们正在更新ID为3的学生的记录-
update StudentInformations set StudentFirstName = 'Robert', StudentLastName = 'Brown' where -> StudentId = 3; Rows matched − 1 Changed − 1 Warnings − 0
使用select语句检查表中的更新值。查询如下-
select *from StudentInformations;
以下是输出-
+-----------+------------------+-----------------+ | StudentId | StudentFirstName | StudentLastName | +-----------+------------------+-----------------+ | 1 | John | Smith | | 2 | Carol | Taylor | | 3 | Robert | Brown | | 4 | Sam | Williams | | 5 | Bob | Davis | | 6 | David | Miller | +-----------+------------------+-----------------+ 6 rows in set (0.00 sec)
现在，您可以在上面看到，StudentId3记录，即StudentFirstName和StudentLastName值已成功更改。