What is the BSON doc (query) for the cmd `show dbs` in MongoDB? -


according getting started mongodb, can use show dbs list of existing databases.

but kind of command running in mongo shell.

my question how write mongodb query (bson) list of databases, , query should sent to?

it's not query, can run listdatabases command against admin database list of databases in bson:

> use admin switched db admin > db.runcommand({listdatabases : 1}) {         "databases" : [                 {                         "name" : "local",                         "sizeondisk" : 83886080,                         "empty" : false                 },         ],         "totalsize" : 83886080,         "ok" : 1 }

most programming language engines mongodb can run commands in addition queries given right syntax. example, in java:

db db = mongo.getdb("admin"); dbobject cmd = new basicdbobject("listdatabases", 1); commandresult result = db.command(cmd);

interestingly, if you're insistent on being query, can query virtual collection $cmd on admin database run commands submitting queries:

> use admin switched db admin > db.$cmd.findone({"listdatabases":1})

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