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

The simple way

Change to the database directory:

cd /var/lib/mysql/

Shut down MySQL... This is important!

/etc/init.d/mysql stop

Okay, this way doesn't work for InnoDB or BDB-Databases.

Rename database:

mv old-name new-name

...or the table...

cd database/

mv old-name.frm new-name.frm

mv old-name.MYD new-name.MYD

mv old-name.MYI new-name.MYI

Restart MySQL

/etc/init.d/mysql start

Done...

OK, this way doesn't work with InnoDB or BDB databases. In this case you have to dump the database and re-import it.

Answer 2

This is what I use:

$ 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;

Answer 3

Most of the answers here are wrong for one of two reasons:

1. You cannot just use RENAME TABLE, because there might be views and triggers. If there are triggers, RENAME TABLE fails
2. You cannot use mysqldump if you want to "quickly" (as requested in the question) rename a big database

Percona has a blog post about how to do this well: https://www.percona.com/blog/2013/12/24/renaming-database-schema-mysql/

and script posted (made?) by Simon R Jones that does what is suggested in that post. I fixed a bug I found in the script. You can see it here:

https://gist.github.com/ryantm/76944318b0473ff25993ef2a7186213d

Here is a copy of it:

#!/bin/bash
# Copyright 2013 Percona LLC and/or its affiliates
# @see https://www.percona.com/blog/2013/12/24/renaming-database-schema-mysql/
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 "SELECT default_character_set_name FROM information_schema.SCHEMATA WHERE schema_name = '$2'" -sss`
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

Save it to a file called rename_db and make the script executable with chmod +x rename_db then use it like ./rename_db localhost old_db new_db

Answer 4

TodoInTX's stored procedure didn't quite work for me. Here's my stab at it:

-- 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 ([e-mail])

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 ;

Answer 5

Here is a quick way to generate renaming sql script, if you have many tables to move.

SELECT DISTINCT CONCAT('RENAME TABLE ', t.table_schema,'.', t.table_name, ' TO ',     
t.table_schema, "_archive", '.', t.table_name, ';' ) as Rename_SQL 
FROM information_schema.tables t
WHERE table_schema='your_db_name' ;

Answer 6

In MySQL Administrator do the following:

1. Under Catalogs, create a new database schema.
2. Go to Backup and create a backup of the old schema.
3. Execute backup.
4. Go to Restore and open the file created in step 3.
5. Select 'Another Schema' under Target Schema and select the new database schema.
6. Start Restore.
7. Verify new schema and, if it looks good, delete the old one.