如何将MySQL表中的所有记录从大写转换为小写?
mysqlmysqli database
使用 UPDATE 命令和 LOWER() 方法将 MySQL 表中的所有记录从大写转换为小写。
首先我们创建一个表 −
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 命令在表中插入一些记录 −
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 语句显示表中的所有记录的查询 −
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)
下面是在一次调用中更改 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，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)
