# MySQL: determine which database is selected?

## The Question :

262 people think this question is useful

After calling mysql_select_db to grab a database, is there any way to later output the name of the database that is currently selected? This seems very basic but I couldn’t find anything on php.net or stackoverflow (all results are for “no database selected”).

The Question Comments :

## The Answer 1

375 people think this answer is useful

Just use mysql_query (or mysqli_query, even better, or use PDO, best of all) with:

SELECT DATABASE() FROM DUAL;



## Addendum:

There is much discussion over whether or not FROM DUAL should be included in this or not. On a technical level, it is a holdover from Oracle and can safely be removed. If you are inclined, you can use the following instead:

SELECT DATABASE();



That said, it is perhaps important to note, that while FROM DUAL does not actually do anything, it is valid MySQL syntax. From a strict perspective, including braces in a single line conditional in JavaScript also does not do anything, but it is still a valid practice.

## The Answer 2

99 people think this answer is useful
SELECT DATABASE();



p.s. I didn’t want to take the liberty of modifying @cwallenpoole’s answer to reflect the fact that this is a MySQL question and not an Oracle question and doesn’t need DUAL.

## The Answer 3

53 people think this answer is useful

You can always use STATUS command to get to know Current database & Current User

## The Answer 4

9 people think this answer is useful

In the comments of http://www.php.net/manual/de/function.mysql-db-name.php I found this one from ericpp % bigfoot.com:

If you just need the current database name, you can use MySQL’s SELECT DATABASE() command:

<?php
function mysql_current_db() {
$r = mysql_query("SELECT DATABASE()") or die(mysql_error()); return mysql_result($r,0);
}
?>



## The Answer 5

4 people think this answer is useful

Another way for filtering the database with specific word.

SHOW DATABASES WHERE Database LIKE '<yourDatabasePrefixHere>%'
or
SHOW DATABASES LIKE '<yourDatabasePrefixHere>%';



Example:

SHOW DATABASES WHERE Database LIKE 'foobar%'
foobar_animal
foobar_humans_gender
foobar_objects



## The Answer 6

3 people think this answer is useful
@mysql_result(mysql_query("SELECT DATABASE();"),0)



If no database selected, or there is no connection it returns NULL otherwise the name of the selected database.

## The Answer 7

2 people think this answer is useful

slightly off-topic (using the CLI instead of PHP), but still worth knowing: You can set the prompt to display the default database by using any of the following

mysql --prompt='\d> '
export MYSQL_PS1='\d> '



or once inside

prompt \d>\_
\R \d>\_



## The Answer 8

1 people think this answer is useful

SELECT DATABASE() worked in PHPMyAdmin.

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