MySQL 如何在单个调用中更改MySQL表中每个字段的大小写?

您可以使用update和lower()函数来进行此操作。让我们首先创建一张表-

mysql> create table DemoTable
(
   Id varchar(100),
   StudentFirstName varchar(20),
   StudentLastName varchar(20),
   StudentCountryName varchar(10)
);
Query OK, 0 rows affected (0.61 sec)

使用insert命令将一些记录插入表中-

mysql> insert into DemoTable values('STU-101','John','Smith','US');
Query OK, 1 row affected (0.59 sec)
mysql> insert into DemoTable values('STU-102','John','Doe','UK');
Query OK, 1 row affected (0.15 sec)
mysql> insert into DemoTable values('STU-103','David','Miller','AUS');
Query OK, 1 row affected (0.19 sec)

以下是使用select语句从表中显示所有记录的查询-

mysql> select *from DemoTable;

这将产生以下输出-

+---------+------------------+-----------------+--------------------+
| Id      | StudentFirstName | StudentLastName | StudentCountryName |
+---------+------------------+-----------------+--------------------+
| STU-101 | John             | Smith           | US                 |
| STU-102 | John             | Doe             | UK                 |
| STU-103 | David            | Miller          | AUS                |
+---------+------------------+-----------------+--------------------+
3 rows in set (0.00 sec)

以下是在单个调用中更改MySQL表中每个字段的大小写的查询-

mysql> update DemoTable
   set Id=lower(Id),
   StudentFirstName=lower(StudentFirstName),
   StudentLastName=lower(StudentLastName),
   StudentCountryName=lower(StudentCountryName);
Query OK, 3 rows affected (0.22 sec)
Rows matched : 3 Changed : 3 Warnings : 0

使用select语句显示表中的所有记录以检查上述查询中所做的更改-

mysql> select *from DemoTable;

这将产生以下输出-

+---------+------------------+-----------------+--------------------+
| Id      | StudentFirstName | StudentLastName | StudentCountryName |
+---------+------------------+-----------------+--------------------+
| stu-101 | john             | smith           | us                 |
| stu-102 | john             | doe             | uk                 |
| stu-103 | david            | miller          | aus                |
+---------+------------------+-----------------+--------------------+
3 rows in set (0.00 sec)

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