这是我所使用的:

$ mysqldump -u root -p olddb >~/olddb.sql
$ mysql -u root -p
mysql> create database newdb;
mysql> use newdb
mysql> source ~/olddb.sql
mysql> drop database olddb;

TodoInTX的存储过程不太适合我。以下是我的尝试:

-- stored procedure rename_db: Rename a database my means of table copying.
-- Caveats: 
-- Will clobber any existing database with the same name as the 'new' database name.
-- ONLY copies tables; stored procedures and other database objects are not copied.
-- Tomer Altman (taltman@ai.sri.com)

delimiter //
DROP PROCEDURE IF EXISTS rename_db;
CREATE PROCEDURE rename_db(IN old_db VARCHAR(100), IN new_db VARCHAR(100))
BEGIN
    DECLARE current_table VARCHAR(100);
    DECLARE done INT DEFAULT 0;
    DECLARE old_tables CURSOR FOR select table_name from information_schema.tables where table_schema = old_db;
    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1;

    SET @output = CONCAT('DROP SCHEMA IF EXISTS ', new_db, ';'); 
    PREPARE stmt FROM @output;
    EXECUTE stmt;

    SET @output = CONCAT('CREATE SCHEMA IF NOT EXISTS ', new_db, ';');
    PREPARE stmt FROM @output;
    EXECUTE stmt;

    OPEN old_tables;
    REPEAT
        FETCH old_tables INTO current_table;
        IF NOT done THEN
        SET @output = CONCAT('alter table ', old_db, '.', current_table, ' rename ', new_db, '.', current_table, ';');
        PREPARE stmt FROM @output;
        EXECUTE stmt;

        END IF;
    UNTIL done END REPEAT;

    CLOSE old_tables;

END//
delimiter ;

三个选项:

创建新数据库，关闭服务器，将文件从一个数据库文件夹移动到另一个数据库文件夹，然后重新启动服务器。注意，这只在所有表都是MyISAM的情况下才有效。 创建新的数据库，使用Create TABLE…LIKE语句，然后使用INSERT…从语句中选择*。 使用mysqldump并重新加载该文件。

UPDATE `db`SET Db = 'new_db_name' where Db = 'old_db_name';

这里已经有很多非常好的答案，但我没有看到PHP版本。这将在大约一秒钟内复制一个800M DB。

$oldDbName = "oldDBName";
$newDbName = "newDBName";
$oldDB     = new mysqli("localhost", "user", "pass", $oldDbName);
if($oldDB->connect_errno){
    echo "Failed to connect to MySQL: (" . $oldDB->connect_errno . ") " . $oldDB->connect_error;
    exit;
}
$newDBQuery = "CREATE DATABASE IF NOT EXISTS {$newDbName}";
$oldDB->query($newDBQuery);
$newDB = new mysqli("localhost", "user", "pass");
if($newDB->connect_errno){
    echo "Failed to connect to MySQL: (" . $newDB->connect_errno . ") " . $newDB->connect_error;
    exit;
}

$tableQuery  = "SHOW TABLES";
$tableResult = $oldDB->query($tableQuery);
$renameQuery = "RENAME TABLE\n";
while($table = $tableResult->fetch_array()){
    $tableName = $table["Tables_in_{$oldDbName}"];
    $renameQuery .= "{$oldDbName}.{$tableName} TO {$newDbName}.{$tableName},";
}
$renameQuery = substr($renameQuery, 0, strlen($renameQuery) - 1);
$newDB->query($renameQuery);

TodoInTx的解决方案和user757945的改编解决方案都不适合我的MySQL 5.5.16，所以这里是我的改编版本:

DELIMITER //
DROP PROCEDURE IF EXISTS `rename_database`;
CREATE PROCEDURE `rename_database` (IN `old_name` VARCHAR(20), IN `new_name` VARCHAR(20))
BEGIN
  DECLARE `current_table_name` VARCHAR(20);
  DECLARE `done` INT DEFAULT 0;
  DECLARE `table_name_cursor` CURSOR FOR SELECT `table_name` FROM `information_schema`.`tables` WHERE (`table_schema` = `old_name`);
  DECLARE CONTINUE HANDLER FOR NOT FOUND SET `done` = 1;

  SET @sql_string = CONCAT('CREATE DATABASE IF NOT EXISTS `', `new_name` , '`;');
  PREPARE `statement` FROM @sql_string;
  EXECUTE `statement`;
  DEALLOCATE PREPARE `statement`;

  OPEN `table_name_cursor`;
  REPEAT
    FETCH `table_name_cursor` INTO `current_table_name`;
    IF NOT `done` THEN

      SET @sql_string = CONCAT('RENAME TABLE `', `old_name`, '`.`', `current_table_name`, '` TO `', `new_name`, '`.`', `current_table_name`, '`;');
      PREPARE `statement` FROM @sql_string;
      EXECUTE `statement`;
      DEALLOCATE PREPARE `statement`;

    END IF;
  UNTIL `done` END REPEAT;
  CLOSE `table_name_cursor`;

  SET @sql_string =  CONCAT('DROP DATABASE `', `old_name`, '`;');
  PREPARE `statement` FROM @sql_string;
  EXECUTE `statement`;
  DEALLOCATE PREPARE `statement`;
END//
DELIMITER ;

希望它能帮助到像我这样处境的人!注意:@sql_string之后将在会话中逗留。不使用它，我就无法写出这个函数。