一个文档，您想将所有“源”值更新为大写。

{"_id" : NumberLong(1),"country" : "au","source" : "apnic"
}
{"_id" : NumberLong(2),"country" : "cn","source" : "apnic"
}
{"_id" : NumberLong(3),"country" : "us","source" : "arin"
}

解

不确定是否有任何就绪函数，但是您可以编写脚本将值更新为大写：

db.whois.find({ "source": { "$exists": true } }).forEach(function(doc) {db.whois.update({ "_id": doc._id },{ "$set": { "source": doc.source.toUpperCase() } });
});

输出量

{"_id" : NumberLong(1),"country" : "au","source" : "APNIC",
}
{"_id" : NumberLong(2),"country" : "cn","source" : "APNIC",
}
{"_id" : NumberLong(3),"country" : "us","source" : "ARIN",
}

做完了

翻译自: https://mkyong.com/mongodb/mongodb-update-to-upper-case/