使用MongoDB随机化唯一数据，并以单词John开头放置emailid的值
> db.demo561.insertOne({EmailId:null});{
"acknowledged" : true, "insertedId" : ObjectId("5e8f490454b4472ed3e8e86c")
}
> db.demo561.insertOne({EmailId:null});{
"acknowledged" : true, "insertedId" : ObjectId("5e8f490654b4472ed3e8e86d")
}
> db.demo561.insertOne({EmailId:null});{
"acknowledged" : true, "insertedId" : ObjectId("5e8f490a54b4472ed3e8e86e")
}在find()方法的帮助下显示集合中的所有文档-
> db.demo561.find();
这将产生以下输出-
{ "_id" : ObjectId("5e8f490454b4472ed3e8e86c"), "EmailId" : null }
{ "_id" : ObjectId("5e8f490654b4472ed3e8e86d"), "EmailId" : null }
{ "_id" : ObjectId("5e8f490a54b4472ed3e8e86e"), "EmailId" : null }以下是使用MongoDB随机化唯一数据的查询-
> db.demo561.find().forEach(function(doc){
... db.demo561.update({_id : doc._id}, {$set:{
... EmailId:'John'+Math.random()*100000000000000000+'@'+Math.random()*100000000000000000+'.com'
... }})
... })在find()方法的帮助下显示集合中的所有文档-
> db.demo561.find();
这将产生以下输出-
{ "_id" : ObjectId("5e8f490454b4472ed3e8e86c"), "EmailId" : "John23607829153155868@62688631475897960.com" }
{ "_id" : ObjectId("5e8f490654b4472ed3e8e86d"), "EmailId" : "John63351292234094710@79460595429439740.com" }
{ "_id" : ObjectId("5e8f490a54b4472ed3e8e86e"), "EmailId" : "John71315584787457890@99884571221675000.com" }