MySQL: determine which database is selected?

mysql
andrewtweber picture andrewtweber · Nov 11, 2011 · Viewed 218k times · Source

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").

Answer

cwallenpoole picture cwallenpoole · Nov 11, 2011

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.

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