USE MyDatabase;
How do I UNUSE MyDatabase or DESELECT MyDatabase so I can use SHOW DATABASES again? What is the opposite of USE?
There is no UNUSE. You just select another database and USE it.
Bruce Daniels presented an answer at https://web.archive.org/web/20160130220207/https://dev.mysql.com/doc/refman/5.5/en/use.html.
It goes like:
CREATE DATABASE foofoofooweird;
USE foofoofooweird;
DROP DATABASE foofoofooweird;
Et voila, no database is in use.
To be clear, the hack is to CREATE, USE, then DROP (delete) a temporary placeholder database.
It is NOT advocating dropping (deleting) any database you actually use!
All credits to Bruce Daniels!
MySQL cmd can't make "unuse" function, if you want to change between databases, just use the USE DATABASENAME; command.
As said in other answers, you simply can switch to another database, but if you just want to use none of the databases you can quit from mysql session and start it again.
\q
mysql -u username -p password
I don't see clear reason to do this, but it answers the question.
There is no command UNUSE as USE db_name,
but instead you can use the same USE statement but with the replacing db name.
Suppose i am now working in world db and want to chanage to employee
intially i have entered USE world now i will simply enter use employees
Related
I started learning SQL but just in my first query, failed, i was doing exactly the same as the mentor explaining in the course but somehow his code worked mine not.
I also tried this query on PopSql it also did not work.
What is wrong here?
You need to select the database you are running this query on.
To do this via MySQL Workbench:
Click on the 'Schemas' tab highlighted below:
Then double click on the name of the database you are trying to run the query on, the database name will be bolded once selected.
You need to tell MySQL which database to use:
USE database_name;
before you create a table.
In case the database does not exist, you need to create it as:
CREATE DATABASE database_name;
followed by:
USE database_name;
This question already has answers here:
How do I rename a MySQL database (change schema name)?
(46 answers)
Closed 9 days ago.
How can I change the database name of my database?
I tried to use the rename database command, but on the documents about it it is said that it is dangerous to use. Then what should I need to do to rename my database name?
For example, if I want to rename my database to this.
database1 -> database2?
Follow bellow steps:
shell> mysqldump -hlocalhost -uroot -p database1 > dump.sql
mysql> CREATE DATABASE database2;
shell> mysql -hlocalhost -uroot -p database2 < dump.sql
If you want to drop database1 otherwise leave it.
mysql> DROP DATABASE database1;
Note : shell> denote command prompt and mysql> denote mysql prompt.
I don't think it's possible.
You can use mysqldump to dump the data and then create a schema with your new name and then dump the data into that new database.
Unfortunately, MySQL does not explicitly support that (except for dumping and reloading database again).
From http://dev.mysql.com/doc/refman/5.1/en/rename-database.html:
13.1.32. RENAME DATABASE Syntax
RENAME {DATABASE | SCHEMA} db_name TO new_db_name;
This statement was added in MySQL 5.1.7 but was found to be dangerous and was removed in MySQL 5.1.23. ... Use of this statement could result in loss of database contents, which is why it was removed. Do not use RENAME DATABASE in earlier versions in which it is present.
"As long as two databases are on the same file system, you can use RENAME TABLE to move a table from one database to another"
-- ensure the char set and collate match the existing database.
SHOW VARIABLES LIKE 'character_set_database';
SHOW VARIABLES LIKE 'collation_database';
CREATE DATABASE `database2` DEFAULT CHARACTER SET = `utf8` DEFAULT COLLATE = `utf8_general_ci`;
RENAME TABLE `database1`.`table1` TO `database2`.`table1`;
RENAME TABLE `database1`.`table2` TO `database2`.`table2`;
RENAME TABLE `database1`.`table3` TO `database2`.`table3`;
http://dev.mysql.com/doc/refman/5.7/en/rename-table.html
You can change the database name using MySQL interface.
Go to http://www.hostname.com/phpmyadmin
Go to database which you want to rename. Next, go to the operation tab. There you will find the input field to rename the database.
InnoDB supports RENAME TABLE statement to move table from one database to another. To use it programmatically and rename database with large number of tables, I wrote a couple of procedures to get the job done.
You can check it out here - SQL script #Gist
To use it simply call the renameDatabase procedure.
CALL renameDatabase('old_name', 'new_name');
Tested on MariaDB and should work ideally on all RDBMS using InnoDB transactional engine.
I agree with above answers and tips but there is a way to change database name with phpmyadmin
Renaming the Database
From cPanel, click on phpMyAdmin. (It should open in a new tab.)
Click on the database you wish to rename in the left hand column.
Click on the Operations tab.
Where it says "Rename database to:" enter the new database name.
Click the Go button.
When it asks you to want to create the new database and drop the old database, click OK to proceed. (This is a good time to make sure you spelled the new name correctly.)
Once the operation is complete, click OK when asked if you want to reload the database.
here's the video tutorial:
http://support.hostgator.com/articles/specialized-help/technical/phpmyadmin/how-to-rename-a-database-in-phpmyadmin
Another way to rename the database or taking an image of the database is by using the reverse engineering option in the database tab. It will create an ER diagram for the database. Rename the schema there.
After that, go to the File menu and go to export and forward engineer the database.
Then you can import the database.
Sequel Ace database client have a rename database functionality. Select the database you would like to edit and click Database in the menu and then click Rename Database from the dropdown. Rename the database and ckick rename. Done!
After much aggravation this is what I have found to work"simply".
First thing, I am using MYSQL Workbench and the import would not work as it should, as the import dump file would always revert to the original schema name.
I spent several hours trying every thing to no avail,all for a spelling error.
I solved the issue by opening one of the .sql dump files in notebook and hand editing the typo's of the schema name, take care to rename all instances schema name has three in the beginning, save the file and then import. this worked perfectly for me and hope that it will help others looking for the simple answer to changing database names/schema names.
One more tip that I have found true, when programs do not do as they should go to the "source" literally find the source code.
Hope this helps someone
Low rep so they wont let me comment on the prior/post answer(it keeps changing rank or position), so I added it here. reverse engineering will work fine as long as there is no data in the sever table. if data exists and you try to update the server after the name change it will either pull an error or just create a new database/schema with no data, I know I tried ten times to no avail.
The above works simply and avoids headaches, as one can review the SQL code for other errors if any or change table names or creation data.
the .sql file is just a compiled SQL code so in theory one could copy and add it through PHP or the script console of the database management tool.
You can use below command
alter database Testing modify name=LearningSQL;
Old Database Name = Testing,
New Database Name = LearningSQL
Go to data directory and try this:
mv database1 database2
It works for me on a 900 MB database size.
Try:
RENAME database1 TO database2;
Is there a concise way to ignore multiple tables using mysql --ignore-table?
The documentation says that --ignore-table must be used for each table.
I have to ignore around 20 tables so the command is going to be huge
This must be run via the command line
Go the whitelist route instead of the blacklist route. From the man page:
mysqldump [options] [db_name [tbl_name ...]]
You still have to type everything out, but at least you don't have to continuously type the --ignore-table flag.
Try using MySQL Workbench to build the command. It'll give the option to specify which tables you want via checkboxes.
If you need to, you can copy and paste the command from the Export Progress tab.
How do I stop using a database?
To start mysql, you can use:
mysql -u root -pXXXX<ENTER>
At this time, no database is selected. We'll call this
state 1
To select (or use) a database:
use "MyDB";
.....My operations or queries
Now, I want to return to state 1 (without any database selected). How I can do that? I can select another database, but I don't want to do that.
What you are asking for is not possible. The only way to return to that state is to disconnect and then reconnect.
If you are just looking to switch away from your current db, you can switch to a system database, such as the internal "mysql" database:
use mysql
Or you could create an empty database and use that:
create database empty;
use empty
Try prompt.
From the MySQL manual:
Reconfigure the mysql prompt to the given string. The special
character sequences that can be used in the prompt are described later
in this section.
If you specify the prompt command with no argument, mysql resets the prompt to the default of mysql>.
Ike Walker's answer is on the right track me thinks.
Create a swap space, or you could just halt the server (stop the process) and restart it I suppose. That defeats the purpose of the server—but it would for sure wind up where you want it with no database in 'use'.
I'm certain you know this, but I mention here just in case. You never know. Someone might not know it is possible to do this.
Hi I need to backup MySQL database and then deploy it on another MySQL server.
The problem is, I need it backup without data , just script which creates database, tables, procedures, users, resets autoincrements etc. ...
I tried MySQL administrator tool (Windows) and UNchecked "complete inserts check box", but it still created it ...
Thanks in advance
use mysqldump with option -d or --no-data
don't forget option -R to get the procedures
this page could help you: http://dev.mysql.com/doc/refman/5.0/en/mysqldump.html
From within phpMyAdmin you can export the structure, with or without the data. The only thing I'm not sure of, is wether it exports users as well. If you like, I can test that tomorrow morning. It exports users too. You can check all sorts of options.
(source: obviousmatter.com)
According to the page, there isn't a good way to dump the routines and have them easily able to be recreated.
What they suggest is to dump the mysql.proc table directly. Including all the data.
Then use your myback.sql to restore the structure. Then restore the mysql.proc table with all of its data.
"... If you require routines to be re-created with their original timestamp attributes, do not use --routines. Instead, dump and reload the contents of the mysql.proc table directly, using a MySQL account that has appropriate privileges for the mysql database. ..."