How do I quickly rename a MySQL database (change s

Question

The MySQL manual at MySQL covers this.

Usually I just dump the database and reimport it with a new name. This is not an option for very big databases. Apparently RENAME {DATABASE | SCHEMA} db_name TO new_db_name; does bad things, exist only in a handful of versions, and is a bad idea overall.

This needs to work with InnoDB, which stores things very differently than MyISAM.

Answer 1

For InnoDB, the following seems to work: create the new empty database, then rename each table in turn into the new database:

RENAME TABLE old_db.table TO new_db.table;

You will need to adjust the permissions after that.

For scripting in a shell, you can use either of the following:

mysql -u username -ppassword old_db -sNe 'show tables' | while read table; \ 
    do mysql -u username -ppassword -sNe "rename table old_db.$table to new_db.$table"; done

Or

for table in `mysql -u root -ppassword -s -N -e "use old_db;show tables from old_db;"`; do mysql -u root -ppassword -s -N -e "use old_db;rename table old_db.$table to new_db.$table;"; done;

Notes: there is no space between the option -p and the password. If your database has no password, remove the -u username -ppassword part.

Also, if you have stored procedures, you can copy them afterwards:

mysqldump -R old_db | mysql new_db

Answer 2

If you are using phpMyAdmin you can go to the "operations" tab once you have selected the database you want to rename. Then go to the last section "copy database to" (or something like that), give a name, and select the options below. In this case, I guess you must select "structure and data" and "create database before copying" checkboxes and, finally, press the "go" button in that section.

By the way, I'm using phpMyAdmin in Spanish so I'm not sure what the names of the sections are in English.

Answer 3

Three options:

1. Create the new database, bring down the server, move the files from one database folder to the other, and restart the server. Note that this will only work if ALL of your tables are MyISAM.

2. Create the new database, use CREATE TABLE ... LIKE statements, and then use INSERT ... SELECT * FROM statements.

3. Use mysqldump and reload with that file.

Answer 4

Well there are 2 methods:

Method 1: A well-known method for renaming database schema is by dumping the schema using Mysqldump and restoring it in another schema, and then dropping the old schema (if needed).

From Shell

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

Although the above method is easy, it is time and space consuming. What if the schema is more than a 100GB? There are methods where you can pipe the above commands together to save on space, however it will not save time.

To remedy such situations, there is another quick method to rename schemas, however, some care must be taken while doing it.

Method 2: MySQL has a very good feature for renaming tables that even works across different schemas. This rename operation is atomic and no one else can access the table while its being renamed. This takes a short time to complete since changing a table’s name or its schema is only a metadata change. Here is procedural approach at doing the rename:

Create the new database schema with the desired name. Rename the tables from old schema to new schema, using MySQL’s “RENAME TABLE” command. Drop the old database schema. If there are views, triggers, functions, stored procedures in the schema, those will need to be recreated too. MySQL’s “RENAME TABLE” fails if there are triggers exists on the tables. To remedy this we can do the following things :

1) Dump the triggers, events and stored routines in a separate file. This done using -E, -R flags (in addition to -t -d which dumps the triggers) to the mysqldump command. Once triggers are dumped, we will need to drop them from the schema, for RENAME TABLE command to work.

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

2) Generate a list of only “BASE” tables. These can be found using a query on information_schema.TABLES table.

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

3) Dump the views in an out file. Views can be found using a query on the same information_schema.TABLES table.

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) Drop the triggers on the current tables in the old_schema.

mysql> DROP TRIGGER <trigger_name>;
...

5) Restore the above dump files once all the “Base” tables found in step #2 are renamed.

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.

The Percona Remote DBA team have written a script called “rename_db” that works in the following way :

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

To demonstrate the use of this script, used a sample schema “emp”, created test triggers, stored routines on that schema. Will try to rename the database schema using the script, which takes some seconds to complete as opposed to time consuming dump/restore method.

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               |
+--------------------+

As you can see in the above output the database schema “emp” was renamed to “emp_test” in less than a second. Lastly, This is the script from Percona that is used above for “method 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

Answer 5

Here is a batch file I wrote to automate it from the command line, but it for Windows/MS-DOS.

Syntax is rename_mysqldb database newdatabase -u [user] -p[password]

:: ***************************************************************************
:: FILE: RENAME_MYSQLDB.BAT
:: ***************************************************************************
:: DESCRIPTION
:: This is a Windows /MS-DOS batch file that automates renaming a MySQL database 
:: by using MySQLDump, MySQLAdmin, and MySQL to perform the required tasks.
:: The MySQL\bin folder needs to be in your environment path or the working directory.
::
:: WARNING: The script will delete the original database, but only if it successfully
:: created the new copy. However, read the disclaimer below before using.
::
:: DISCLAIMER
:: This script is provided without any express or implied warranties whatsoever.
:: The user must assume the risk of using the script.
::
:: You are free to use, modify, and distribute this script without exception.
:: ***************************************************************************

:INITIALIZE
@ECHO OFF
IF [%2]==[] GOTO HELP
IF [%3]==[] (SET RDB_ARGS=--user=root) ELSE (SET RDB_ARGS=%3 %4 %5 %6 %7 %8 %9)
SET RDB_OLDDB=%1
SET RDB_NEWDB=%2
SET RDB_DUMPFILE=%RDB_OLDDB%_dump.sql
GOTO START

:START
SET RDB_STEP=1
ECHO Dumping "%RDB_OLDDB%"...
mysqldump %RDB_ARGS% %RDB_OLDDB% > %RDB_DUMPFILE%
IF %ERRORLEVEL% NEQ 0 GOTO ERROR_ABORT
SET RDB_STEP=2
ECHO Creating database "%RDB_NEWDB%"...
mysqladmin %RDB_ARGS% create %RDB_NEWDB%
IF %ERRORLEVEL% NEQ 0 GOTO ERROR_ABORT
SET RDB_STEP=3
ECHO Loading dump into "%RDB_NEWDB%"...
mysql %RDB_ARGS% %RDB_NEWDB% < %RDB_DUMPFILE%
IF %ERRORLEVEL% NEQ 0 GOTO ERROR_ABORT
SET RDB_STEP=4
ECHO Dropping database "%RDB_OLDDB%"...
mysqladmin %RDB_ARGS% drop %RDB_OLDDB% --force
IF %ERRORLEVEL% NEQ 0 GOTO ERROR_ABORT
SET RDB_STEP=5
ECHO Deleting dump...
DEL %RDB_DUMPFILE%
IF %ERRORLEVEL% NEQ 0 GOTO ERROR_ABORT
ECHO Renamed database "%RDB_OLDDB%" to "%RDB_NEWDB%".
GOTO END

:ERROR_ABORT
IF %RDB_STEP% GEQ 3 mysqladmin %RDB_ARGS% drop %NEWDB% --force
IF %RDB_STEP% GEQ 1 IF EXIST %RDB_DUMPFILE% DEL %RDB_DUMPFILE%
ECHO Unable to rename database "%RDB_OLDDB%" to "%RDB_NEWDB%".
GOTO END

:HELP
ECHO Renames a MySQL database.
ECHO Usage: %0 database new_database [OPTIONS]
ECHO Options: Any valid options shared by MySQL, MySQLAdmin and MySQLDump.
ECHO          --user=root is used if no options are specified.
GOTO END    

:END
SET RDB_OLDDB=
SET RDB_NEWDB=
SET RDB_ARGS=
SET RDB_DUMP=
SET RDB_STEP=

Answer 6

in phpmyadmin you can easily rename the database

select database 

  goto operations tab

  in that rename Database to :

  type your new database name and click go

ask to drop old table and reload table data click OK in both

Your database is renamed