I posted this How do I change the database name using MySQL? today after days of head scratching and hair pulling. The solution is quite simple export a schema to a .sql file and open the file and change the database/schema name in the sql CREAT TABLE section at the top. There are three instances or more and may not be at the top of the page if multible schemas are saved to the file. It is posible to edit the entire database this way but I expect that in large databases it could be quite a pain following all instances of a table property or index.

你们这些家伙会为此开枪打死我的，很可能这不会每次都管用，当然，这违反了所有的逻辑……但我刚试过的是…停止MySQL引擎，以root身份登录，并在文件系统级别上简单地重命名数据库....

我在OSX上，只改变了情况，从bedbf到bedbf。令我惊讶的是，它竟然起作用了……

我不建议在生产DB上使用它。我只是做了个实验……

祝你好运! -)

有两种方法:

方法1:一个著名的重命名数据库模式的方法是使用Mysqldump转储模式并将其恢复到另一个模式中，然后删除旧的模式(如果需要)。

从壳

 mysqldump emp > emp.out
 mysql -e "CREATE DATABASE employees;"
 mysql employees < emp.out 
 mysql -e "DROP DATABASE emp;"

虽然上面的方法很简单，但它是时间和空间消耗。如果模式大于100GB怎么办?有一些方法可以将上述命令连接在一起以节省空间，但这不会节省时间。

为了纠正这种情况，有另一种重命名模式的快速方法，但是在执行时必须小心。

方法2:MySQL在重命名表方面有一个非常好的特性，甚至可以跨不同的模式工作。这个重命名操作是原子的，在重命名表时没有其他人可以访问它。这只需要很短的时间就可以完成，因为更改表名或表的模式只是元数据的更改。下面是重命名的过程方法:

使用所需的名称创建新的数据库模式。 使用MySQL的" Rename TABLE "命令将旧模式的表重命名为新模式。 删除旧的数据库模式。 如果模式中有视图、触发器、函数、存储过程，也需要重新创建它们。如果表上存在触发器，MySQL的“RENAME TABLE”将失败。为了解决这个问题，我们可以做以下事情:

1)将触发器、事件和存储的例程转储到单独的文件中。在mysqldump命令中使用-E， -R标志(以及转储触发器的-t -d)。一旦触发器被转储，我们将需要从模式中删除它们，以便RENAME TABLE命令能够工作。

 $ mysqldump <old_schema_name> -d -t -R -E > stored_routines_triggers_events.out

2)生成一个只有“BASE”表的列表。可以通过对information_schema的查询找到这些参数。表的表。

 mysql> select TABLE_NAME from information_schema.tables where 
    table_schema='<old_schema_name>' and TABLE_TYPE='BASE TABLE';

3)在输出文件中转储视图。视图可以使用同一个information_schema上的查询来找到。表的表。

mysql> select TABLE_NAME from information_schema.tables where 
   table_schema='<old_schema_name>' and TABLE_TYPE='VIEW';
 $ mysqldump <database> <view1> <view2> … > views.out

4)删除old_schema中当前表上的触发器。

mysql> DROP TRIGGER <trigger_name>;
...

5)在步骤#2中发现的所有“Base”表重命名后恢复上述转储文件。

mysql> RENAME TABLE <old_schema>.table_name TO <new_schema>.table_name;
...
$ mysql <new_schema> < views.out
$ mysql <new_schema> < stored_routines_triggers_events.out

Intricacies with above methods : We may need to update the GRANTS for users such that they match the correct schema_name. These could fixed with a simple UPDATE on mysql.columns_priv, mysql.procs_priv, mysql.tables_priv, mysql.db tables updating the old_schema name to new_schema and calling “Flush privileges;”. Although “method 2″ seems a bit more complicated than the “method 1″, this is totally scriptable. A simple bash script to carry out the above steps in proper sequence, can help you save space and time while renaming database schemas next time.

Percona Remote DBA团队写了一个名为“rename_db”的脚本，其工作方式如下:

[root@dba~]# /tmp/rename_db
rename_db <server> <database> <new_database>

为了演示这个脚本的使用，使用了一个示例模式“emp”，创建测试触发器，在该模式上存储例程。将尝试使用脚本重命名数据库模式，与耗时的转储/还原方法相比，重命名数据库模式需要几秒钟的时间。

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| emp                |
| mysql              |
| performance_schema |
| test               |
+--------------------+


[root@dba ~]# time /tmp/rename_db localhost emp emp_test
create database emp_test DEFAULT CHARACTER SET latin1
drop trigger salary_trigger
rename table emp.__emp_new to emp_test.__emp_new
rename table emp._emp_new to emp_test._emp_new
rename table emp.departments to emp_test.departments
rename table emp.dept to emp_test.dept
rename table emp.dept_emp to emp_test.dept_emp
rename table emp.dept_manager to emp_test.dept_manager
rename table emp.emp to emp_test.emp
rename table emp.employees to emp_test.employees
rename table emp.salaries_temp to emp_test.salaries_temp
rename table emp.titles to emp_test.titles
loading views
loading triggers, routines and events
Dropping database emp

real    0m0.643s
user    0m0.053s
sys     0m0.131s


mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| emp_test           |
| mysql              |
| performance_schema |
| test               |
+--------------------+

正如您在上面的输出中看到的，数据库模式“emp”在不到一秒钟的时间内就被重命名为“emp_test”。最后，这是来自Percona的脚本，上面用于“方法2″”。

#!/bin/bash
# Copyright 2013 Percona LLC and/or its affiliates
set -e
if [ -z "$3" ]; then
    echo "rename_db <server> <database> <new_database>"
    exit 1
fi
db_exists=`mysql -h $1 -e "show databases like '$3'" -sss`
if [ -n "$db_exists" ]; then
    echo "ERROR: New database already exists $3"
    exit 1
fi
TIMESTAMP=`date +%s`
character_set=`mysql -h $1 -e "show create database $2\G" -sss | grep ^Create | awk -F'CHARACTER SET ' '{print $2}' | awk '{print $1}'`
TABLES=`mysql -h $1 -e "select TABLE_NAME from information_schema.tables where table_schema='$2' and TABLE_TYPE='BASE TABLE'" -sss`
STATUS=$?
if [ "$STATUS" != 0 ] || [ -z "$TABLES" ]; then
    echo "Error retrieving tables from $2"
    exit 1
fi
echo "create database $3 DEFAULT CHARACTER SET $character_set"
mysql -h $1 -e "create database $3 DEFAULT CHARACTER SET $character_set"
TRIGGERS=`mysql -h $1 $2 -e "show triggers\G" | grep Trigger: | awk '{print $2}'`
VIEWS=`mysql -h $1 -e "select TABLE_NAME from information_schema.tables where table_schema='$2' and TABLE_TYPE='VIEW'" -sss`
if [ -n "$VIEWS" ]; then
    mysqldump -h $1 $2 $VIEWS > /tmp/${2}_views${TIMESTAMP}.dump
fi
mysqldump -h $1 $2 -d -t -R -E > /tmp/${2}_triggers${TIMESTAMP}.dump
for TRIGGER in $TRIGGERS; do
    echo "drop trigger $TRIGGER"
    mysql -h $1 $2 -e "drop trigger $TRIGGER"
done
for TABLE in $TABLES; do
    echo "rename table $2.$TABLE to $3.$TABLE"
    mysql -h $1 $2 -e "SET FOREIGN_KEY_CHECKS=0; rename table $2.$TABLE to $3.$TABLE"
done
if [ -n "$VIEWS" ]; then
    echo "loading views"
    mysql -h $1 $3 < /tmp/${2}_views${TIMESTAMP}.dump
fi
echo "loading triggers, routines and events"
mysql -h $1 $3 < /tmp/${2}_triggers${TIMESTAMP}.dump
TABLES=`mysql -h $1 -e "select TABLE_NAME from information_schema.tables where table_schema='$2' and TABLE_TYPE='BASE TABLE'" -sss`
if [ -z "$TABLES" ]; then
    echo "Dropping database $2"
    mysql -h $1 $2 -e "drop database $2"
fi
if [ `mysql -h $1 -e "select count(*) from mysql.columns_priv where db='$2'" -sss` -gt 0 ]; then
    COLUMNS_PRIV="    UPDATE mysql.columns_priv set db='$3' WHERE db='$2';"
fi
if [ `mysql -h $1 -e "select count(*) from mysql.procs_priv where db='$2'" -sss` -gt 0 ]; then
    PROCS_PRIV="    UPDATE mysql.procs_priv set db='$3' WHERE db='$2';"
fi
if [ `mysql -h $1 -e "select count(*) from mysql.tables_priv where db='$2'" -sss` -gt 0 ]; then
    TABLES_PRIV="    UPDATE mysql.tables_priv set db='$3' WHERE db='$2';"
fi
if [ `mysql -h $1 -e "select count(*) from mysql.db where db='$2'" -sss` -gt 0 ]; then
    DB_PRIV="    UPDATE mysql.db set db='$3' WHERE db='$2';"
fi
if [ -n "$COLUMNS_PRIV" ] || [ -n "$PROCS_PRIV" ] || [ -n "$TABLES_PRIV" ] || [ -n "$DB_PRIV" ]; then
    echo "IF YOU WANT TO RENAME the GRANTS YOU NEED TO RUN ALL OUTPUT BELOW:"
    if [ -n "$COLUMNS_PRIV" ]; then echo "$COLUMNS_PRIV"; fi
    if [ -n "$PROCS_PRIV" ]; then echo "$PROCS_PRIV"; fi
    if [ -n "$TABLES_PRIV" ]; then echo "$TABLES_PRIV"; fi
    if [ -n "$DB_PRIV" ]; then echo "$DB_PRIV"; fi
    echo "    flush privileges;"
fi

I).没有办法直接改变现有数据库的名称 但你可以透过以下步骤达到目标:- 1).创建newdb。 2).使用newdb。 3). create table table_name(select * from olddb.table_name);

通过这样做，你复制数据从表的olddb和插入那些在newdb表。给表的名称相同。

II).重命名表old_db。table_name TO new_db.table_name;

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 ;

ALTER DATABASE是MySQL建议的解决方法，RENAME DATABASE被删除。

从13.1.32 RENAME数据库语法:

RENAME {DATABASE | SCHEMA} db_name TO new_db_name;

此语句是在MySQL 5.1.7中添加的，但被发现是危险的，在MySQL 5.1.23中被删除。