Check if mongodb database exists?

Question

Is there a possibility to check if a mongo database allready exists?

Answer 1

From the shell, if you want to explicitely check that a DB exists:

db.getMongo().getDBNames().indexOf("mydb");

Will return '-1' if "mydb" does not exist.

To use this from the shell:

if [ $(mongo localhost:27017 --eval 'db.getMongo().getDBNames().indexOf("mydb")' --quiet) -lt 0 ]; then
    echo "mydb does not exist"
else
    echo "mydb exists"
fi