objectid

1. Conditional operator= This operator does not have to explain more, the most commonly used is the simplestDb.collection.find ({"field": {$gt: Value}}); Greater than: field > ValueDb.collection.find ({"field": {$lt: Value}}); Less than: Field

In the previous article we talked about MongoDB's CRUD basic operations http://blog.csdn.net/stronglyh/article/details/46812579In this case, let's talk about the advanced--------------of MongoDB.A: Various inquiries1: Conditional operator= This

View all data tables> Use ChatRoomSwitched to db ChatRoom> Show collectionsAccountChatSystem. indexesSystem. users Create a data table> Db. createCollection ("Account "){"OK": 1} > Db. createCollection ("Test", {capped: true, size: 10000}) {"OK": 1}{

Overview For the MongoDB storage base Unit Bson Document object, the field value can be a binary type, and based on this feature, we can store the file directly in MongoDB, but there is a limitation because a single Bson object in MongoDB cannot be

MongoDB dbref (Associative insert, query, delete) instance in depth, A,b,c three collection are interrelated. The number is the value of document.The introduction to Dbref can be seen http://blog.csdn.net/crazyjixiang/article/details/6616678 this

Statement: The article is mainly from the "MongoDB actual Combat" a book, the main want to learn MongoDB knowledge through the book, deepen understanding, so write in their own blog, as a record, in the final chapter, there will be a collection of

/opt/mongodb-2.6.6/bin > MONGO1. Querying all local database names> Show DBS2. Switch to the specified database environment (if no database is specified, create a new library)> Use test;3. Created a collection called ' EMP '> db.createcollection ('

MongDB basic learning (5) -- projection, paging, sorting, aggregation, and mongdb Paging MongDB basic learning (5) -- projection, paging, sorting, and aggregation Basic syntax Learning The Chinese New Year is coming soon, tomorrow is a lover, and

MONGDB Basic Learning (v)--projection, pagination, sorting, aggregationThe learning of Basic grammarThe new Year is coming soon, tomorrow is a lover, the day after tomorrow will be a holiday, hope that they can in the holiday before the five and six

1. Basic Enquiry:Constructs the query data.> Db.test.findOne (){"_id": ObjectId ("4fd58ecbb9ac507e96276f1a"),"Name": "Stephen","Age": 35,"Genda": "Male","Email": "[email protected]"}--Multi-criteria query. The following example is equivalent to the

1. Basic Enquiry:Constructs the query data.> Db.test.findOne (){"_id": ObjectId ("4fd58ecbb9ac507e96276f1a"),"Name": "Stephen","Age": 35,"Genda": "Male","Email": "[email protected]"}--Multi-criteria query. The following example is equivalent to the

This article turns from http://www.cnblogs.com/stephen-liu74/archive/2012/08/03/2553803.html1. Basic Enquiry:Constructs the query data.> Db.test.findOne (){"_id": ObjectId ("4fd58ecbb9ac507e96276f1a"),"Name": "Stephen","Age": 35,"Genda":

1. Basic Enquiry:Constructs the query data.> Db.test.findOne (){"_id": ObjectId ("4fd58ecbb9ac507e96276f1a"),"Name": "Stephen","Age": 35,"Genda": "Male","Email": "xxx@163.com"}--Multi-criteria query. The following example is equivalent to the where

There are several ways to store data in ArcGIS from ARCSDE storage to Oracle, including binary long Raw, Esri St_geometry, and sdo_geometry based on Oracle spatial.Recently I have mostly studied the storage method based on Oracle spatial, where the

This article is divided into two points, mainly in the 2nd--java syntax, but in order must first write the original ecological grammar(There is also an article is good: MongoDB advanced query usage Daquan (including MongoDB command syntax and Java

In the previous article we talked about MongoDB's CRUD basic operations http://blog.csdn.net/stronglyh/article/details/46812579In this case, let's talk about the advanced--------------of MongoDB.A: Various inquiries1: Conditional operator= This

1. Connecting to the database [Root@localhost ~]#/apps/mongo/bin/mongoMongoDB Shell version:1.8.1Connecting To:test> 2. Insert Record >j = {name: ' MONGO '};{' name ': ' MONGO '}> t = {x:3};{"X": 3}> Db.things.save (j);> Db.things.save (t);>

Define a variable > var len = 10; For loop here both DB and data can be used as object save is a method that receives a temporary defined object > for (var i = 0; i Writeresult ({"ninserted": 1}) > Db.data. Find (); {"_id": ObjectId ("59

Mongodb:There are collections and document conceptsCollection = = TableDocument = = rows in the database table！！ Database Creation (BOSENRU)> Use BOSENRU;Switched to DB Bosenru！！ Insert a table (T1) into the Bosenrui, insert (x:1) This field (X is

For documents that are updated in addition to replacements, only partial updates to one or more documents are required to use the atom's update modifier to efficiently document updates. The update modifier is a special key in theUsed to specify