Question

For example, I have 1,000 databases, and I want to delete all the databases that begin with a, how do I do it?
(Note that database is not collection)

Answer 1

It takes a little skill, but it’s not too much trouble. A script is done:

db.runCommand({listDatabases: 1}).databases.forEach(function(database) {
 if(database.name.match(/^a/)) {
 db.getDB(database.name).dropDatabase();
 }
 });

Probably throughlistDatabaseGet all the libraries, then find the libraries that meet your criteria, and thendropDatabase()Delete it.
Pay attention to avoid key system libraries, such aslocal,config,adminWait