MongoDB

The series version information of the MongoDB database is as follows: 2.5.0 development version (unstable Version) 2.4.4 latest stable product release 2.2 latest stable version 2.2.4 2.0 latest stable version 2.0.9   There are 2 parts to

{Column: NULL}: The result is that the column value is null or the record does not contain the column field data; {Column: {$ type: 10 }}: the result is data that contains the column field and the value is null; {Column :{$ exists: false }}: the

Indexes can greatly improve the query efficiency. Resume indexes are essential in the database. You can easily create indexes in MongoDB.   Default index _ id _ Enable the MongoDB server, create the database cnblogs, and create the set users.

ArticleDirectory 1. add, delete, and modify 2. Paging Query I wrote a simple example on MongoDB intermittently, involving the basic crud. During the practice, I found many problems, especially the C # Driver Class Library of the

Install MongoDB: Download:Mongodb-win32-x86_64-2008plus-2.0.4(64-bit Edition) Compile MongoDB c driver: Download:Monogo-C-Driver (contains 32-bit unzip C. dll and bson. dll compiled by vs2010) If you do not want to compile the driver, you

Installation files: Official Website http://www.mongodb.org/downloads Select the file to download from the system. 1. decompress the file. Decompress the compressed package, create a folder named mongodbon on the d Drive, and copy all the. exe

View Current Database MongoDB shell version: 1.8 . 1 Connecting to: Test > DBTest   View the list of all databases > Show DBSChatroom 0.03125 GBAdmin (empty)Local (empty)   Switch Database > Use chatroomSwitched to DB

View all users of the current database > Show users{ " _ Id " : Objectid ( " 4deeae26e7516d69948e33 " ), " User " : " Libing " , " Readonly " : False, " PWD " : " 541025c56e577050c3e44efb105e28b6

1. MongoDB sharding knowledge)  Replica set ): The replica set enables each member (member) in the group to have the same data backup in different mongod instances, so that requests from the application server can be accessed (request visit)

Learning document Some MongoDB knowledge points summarized by others Http://wenku.baidu.com/view/4a210120dd36a32d737581a5.htmlgdgf MongoDB manual, English version Http://wenku.baidu.com/view/24954f791711cc7931b71686.html Official website of

SQL statement Mongo query language statement Create Table users (a number, B Number) dB. createcollection ( " mycoll ", {capped: true , size: 100000 }) Insert into users values (1, 1)

First of all, thank you for your support for this tool. After a week of hard work, the latest version of the Tool beta version is released, which is a very important version. Why is this version important? The previous tool only supports one

Data storage: When I introduced journal, I mentioned why MongoDB puts data into the memory instead of directly storing the database storage files. This is related to MongoDB's storage and management operations on database recording files. MongoDB

After MongoDB is started,ProgramThe corresponding parameters, lock files left over from the last time, log files, and so on will be processed accordingly. At the same time, some service threads supporting other parts of the operation will be enabled.

ArticleDirectory Find () Limit result set Findone () Limit () Conditional operators , >= ,! = $ Exists Processing of null values $ Mod $ In & $ Nin $ Not $ Or Array Operations Count () Sort ()

Protected Virtual Configurationbuilder getconfiguration (){VaR Builder = New Configurationbuilder ();Builder. readconnectionstringfromappsettings ( " Tests " ); Return Builder;} // Data ing Class (Key, value) Class Listinfo{

There is no time to write the code, and there are comments in it. gywtest; // select a database $ collection = $ db-> student; // select a collection, set $ Doc = array ("stuname" => "Xiaoming", "stunumber" => "1402040455", "Age" => 28, "Major" => "

Q: What is the use of Mongodb data service? A: First, Mongodb is suitable for storing A large amount of non-business data. Therefore, the Adhesive framework advocates that non-very important non-business data (such as logs, exceptions, and status

In this article, We will practice how to use the Mongodb data service to store new custom data. As we have said before, using the Mongodb data service is as simple as four steps: 1) define an object 2) define metadata 3) configure the Mongodb Data

After May 1, I came back and started this series. After reading the previous series, we can complete a simple website without a database. Of course, there are few websites without database connection. Let's talk about the combination of node. js and