How to check if mysql database exists

Is it possible to check if a (MySQL) database exists after having made a connection.

I know how to check if a table exists in a DB, but I need to check if the DB exists. If not I have to call another piece of code to create it and populate it.

I know this all sounds somewhat inelegant - this is a quick and dirty app.

SELECT SCHEMA_NAME
  FROM INFORMATION_SCHEMA.SCHEMATA
 WHERE SCHEMA_NAME = 'DBName'

If you just need to know if a db exists so you won't get an error when you try to create it, simply use (From here):

CREATE DATABASE IF NOT EXISTS DBName;

A simple way to check if a database exists is:

SHOW DATABASES LIKE 'dbname';

If database with the name 'dbname' doesn't exist, you get an empty set. If it does exist, you get one row.

From the shell like bash

if [[ ! -z "`mysql -qfsBe "SELECT SCHEMA_NAME FROM INFORMATION_SCHEMA.SCHEMATA WHERE SCHEMA_NAME='db'" 2>&1`" ]];
then
  echo "DATABASE ALREADY EXISTS"
else
  echo "DATABASE DOES NOT EXIST"
fi

If you are looking for a php script see below.

$link = mysql_connect('localhost', 'mysql_user', 'mysql_password');
if (!$link) {
  die('Not connected : ' . mysql_error());
}

// make foo the current db
$db_selected = mysql_select_db('foo', $link);
if (!$db_selected) {
  die ('Cannot use foo : ' . mysql_error());
}