我很惊讶地发现，所以我不得不回到这里报告，优秀和维护良好的Interconnect/it SAFE SEARCH and REPLACE ON DATABASE脚本有一些选项可以将表转换为utf8 / unicode，甚至转换为innodb。它是一个脚本，通常用于将数据库驱动的网站(Wordpress, Drupal, Joomla等)从一个域迁移到另一个域。

https://github.com/interconnectit/Search-Replace-DB https://interconnectit.com/products/search-and-replace-for-wordpress-databases/

你需要单独转换每个表:

ALTER TABLE mytable CONVERT TO CHARACTER SET utf8mb4 

(这同样可以转换列)，或者用latin1导出数据库，然后用utf8mb4导入。

您可以在以下级别设置默认排序规则:

http://dev.mysql.com/doc/refman/5.0/en/charset-syntax.html

1)客户端 2)服务器默认 3)数据库默认 4)表默认 5)列

我很惊讶地发现，所以我不得不回到这里报告，优秀和维护良好的Interconnect/it SAFE SEARCH and REPLACE ON DATABASE脚本有一些选项可以将表转换为utf8 / unicode，甚至转换为innodb。它是一个脚本，通常用于将数据库驱动的网站(Wordpress, Drupal, Joomla等)从一个域迁移到另一个域。

https://github.com/interconnectit/Search-Replace-DB https://interconnectit.com/products/search-and-replace-for-wordpress-databases/

您可以简单地将此代码添加到脚本文件

//Database Connection
$host = 'localhost';
$db_name = 'your_database_name';
$db_user =  'your_database_user_name';
$db_pass = 'your_database_user_password';

$con = mysql_connect($host,$db_user,$db_pass);

if(!$con) { echo "Cannot connect to the database ";die();}

  mysql_select_db($db_name);

  $result=mysql_query('show tables');

  while($tables = mysql_fetch_array($result)) {
    foreach ($tables as $key => $value) {
    mysql_query("ALTER TABLE $value CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci");
  }
}

echo "The collation of your database has been successfully changed!";

我不得不在一个有很多基的集群中更改所有数据库、表和列的排序规则。

我使用了一个运行在php 8.1和mysql 8.0上的脚本

function changeCollate() {
    $databases = $this->fetchQueryToArray("SHOW DATABASES LIKE 'nova_%'")->rows;
    foreach ($databases as $value) {
        $db = $value['Database (nova_%)'];
        $this->LOG("-- banco de dados --- " . $db);
        $this->exeQuery("ALTER DATABASE `$db` COLLATE utf8mb4_0900_ai_ci;");
        $this->exeQuery("use $db");
        $tables = $this->fetchQueryToArray("SHOW tables")->rows;
        foreach ($tables as $table) {
            $tb_name = $table["Tables_in_$db"];
            $this->exeQuery("ALTER TABLE `$tb_name` COLLATE utf8mb4_0900_ai_ci;");
            $QUERY = "ALTER TABLE `$db`.`$tb_name`\n";
            $columns = $this->fetchQueryToArray("SHOW FULL COLUMNS FROM $tb_name WHERE Type LIKE 'varchar%' OR Type = 'text' OR Type like 'enum%' OR Type = 'longtext' OR Type = 'mediumtext'")->rows;
            foreach ($columns as $column) {
                $QUERY .= "CHANGE `{$column['Field']}` `{$column['Field']}` {$column['Type']} COLLATE 'utf8mb4_0900_ai_ci'";
                $QUERY .= ($column['Null'] == 'YES') ?  " NULL" : " NOT NULL";
                if ($column['Default']) $QUERY .= " DEFAULT '{$column['Default']}'";
                if ($column['Comment']) $QUERY .= " COMMENT '{$column['Comment']}'";
                $QUERY .= ",\n";
            }
            if ($QUERY == "ALTER TABLE `$db`.`$tb_name`\n") continue;
            $QUERY = substr($QUERY, 0, -2) . ";\n\n";
            $this->exeQuery($QUERY);
        }
    }
}