mongodb normal operation statement

  1 db.c_user.insertOne({
  2     name: "ljm",
  3     pwd: "123456"
  4 }); //插入一个
  5 
  6 db.c_user.insertMany([{
  7     item: "wjl",
  8     age: "25",
  9     tags: ["blank", "red"],
 10     size: {
 11         h: 14,
 12         w: 21
 13     }
 14 },
 15 {
 16     item: "ljm",
 17     age: "18",
 18     tags: ["blank", "red"],
 19     size: {
 20         h: 14,
 21         w: 21
 22     }
 23 }]) ;//插入多个
 24 db.c_type.insertMany([{
 25     item: "wjl",
 26     age: "25",
 27     tags: ["blank", "red"],
 28     size: {
 29         h: 14,
 30         w: 21
 31     }
 32 },
 33 {
 34     item: "ljm",
 35     age: "18",
 36     tags: ["blank", "red"],
 37     size: {
 38         h: 14,
 39         w: 21
 40     }
 41 }]) ;//插入多个
 42 
 43 db.getCollection("c_user").find({}) ;
 44 db.getCollection("c_user").find(); 
 45 db.c_user.find({
 46     name: "ljm"
 47 }) ;//Key:value 查询，相当于where name = ""
 48 
 49 db.getCollection("c_type").find({});
 50 
 51 db.c_user.find({
 52     name: "wjl",
 53     age: {
 54         $lt: 30
 55     }
 56 }); // where .. and ... ,lt < ; gt >
 57 
 58 db.c_user.find({
 59     $or: [{
 60         name: "wjl"
 61     },
 62     {
 63         age: {
 64             $lt: 30
 65         }
 66     }]
 67 }); // where ... or ... 
 68 
 69 db.c_user.find({
 70     name: "wjl",
 71     $or: [{
 72         age: {
 73             $lt: 30
 74         }
 75     },
 76     {
 77         name: /^m/
 78     }]
 79 }); // where and .. or ..
 80 
 81 db.c_user.find({
 82     name: {
 83         $in: ["wjl", "ljm"]
 84     }
 85 }) ;//where in 
 86 db.c_user.updateOne({
 87     "_id": ObjectId("5d034c0de20035e8e98d684a")
 88 },
 89 {
 90     $set: {
 91         pwd: "1315565452",
 92         name: "zhangsan"
 93     }
 94 }); //修改一个
 95 
 96 db.c_user.updateMany({
 97     name: "wjl"
 98 },
 99 {
100     $set: {
101         pwd: "1315565452",
102         name: "zhangsan"
103     }
104 });modify more//
105  
106  db.c_user.replaceOne ({
 107      name: "LJM"
 108  },
 109  {
 110      name: "LJM" ,
 111      Age: "80"
 112 }); // replace a 
113  
114  db.c_user.deleteOne ({
 115      "the _id": the ObjectId ( "5d034fdee20035e8e98d6850" )
 1 16 }); // delete a