db.adminCommand({renameCollection: "db1.test1", to: "db2.test2"})
上述命令实现了将db1下的test1,重命名为db2下的test2,这个命令只修改元数据,开销很小,有了这个功能,要实现db1重命名为db2,只需要遍历db1下所有的集合,重命名到db2下,就实现了renameDatabase的功能,写个js脚本能很快的实现这个功能.
var source = "source";
var dest = "dest";
var colls = db.getSiblingDB(source).getCollectionNames();
for (var i = 0; i < colls.length; i++) {
var from = source + "." + colls[i];
var to = dest + "." + colls[i];
db.adminCommand({renameCollection: from, to: to});
}