在 MySQL 中设置列字符集?
mysqlmysqli database
使用字符集命令设置列字符集。语法如下 −
ALTER TABLE yourTableName MODIFY youColumName type CHARACTER SET anyCharcaterSetName;
您可以使用字符集名称 utf8 或其他名称。要设置列字符集，让我们首先创建一个表。创建表的查询如下 −
mysql> create table setCharsetDemo −> ( −> FirstName varchar(60) −> ); Query OK, 0 rows affected (2.09 sec)
现在您可以借助 show 命令检查当前列字符集。查询如下 −
mysql> show create table setCharsetDemo;
以下是输出 −
+----------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Table | Create Table | +----------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | setCharsetDemo | CREATE TABLE `setcharsetdemo` (`FirstName` varchar(60) COLLATE utf8mb4_unicode_ci DEFAULT NULL) ENGINE = InnoDB DEFAULT CHARSET = utf8mb4 COLLATE = utf8mb4_unicode_ci | +----------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ 1 row in set (0.00 sec)
现在您可以查看上面的示例输出。默认字符集是 utf8mb4。让我们将字符集设置为 utf8mb4 以外的字符集。
我们将字符集设置为 utf8。查询如下 −
mysql> alter table setCharsetDemo modified FirstName varchar(60) CHARACTER SET utf8; Query OK, 0 rows impacted, 1 warning (2.81 sec) Records: 0 Duplicates: 0 Warnings: 1
让我们检查字符集是否已更改。查询如下 −
mysql> show create table setCharsetDemo;
以下输出显示我们已成功更新字符集−
+----------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Table | Create Table | +----------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | setCharsetDemo | CREATE TABLE `setcharsetdemo` (`FirstName` varchar(60) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL) ENGINE = InnoDB DEFAULT CHARSET = utf8mb4 COLLATE = utf8mb4_unicode_ci | +----------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ 1 row in set (0.00 sec)
