manual reference

Linux mongodb installation and data import and export tutorial, mongodb Import and Export How to install mongodb and import and export data in Linux # Viewing the linux release version Cat/etc/issue # View the Linux kernel version Uname-r 1. General

Mongodb Study Notes 05 and mongodb Study NotesEnable authentication Mongod does not have the permission to start by default. You need to specify-auth to start, or set security. authorization to "enabled" in the configuration file"Create user Db.

Memory Management and Memory Management Software IOS memory is managed by referencing the counting mechanism. It can be divided into MRC (manual reference count), ARC (automatic reference count ), Why do we need to learn about memory management? The

This paper describes several methods of memory management.1. What is memory management?Memory management is the optimization of memory resources.2. Three ways to manage memory?OBJECTIVE-C's memory management has three main ways of Arc (automatic

Apsaradb for MongoDB in 8 days-getting started on the first day Learn MongoDB in 8 days-add, delete, query, and modify in the next day 8 days to learn MongoDB-advanced operations on the third day Apsaradb for MongoDB-index operation on the

Variable referencePHP reference allows you to use two variables to point to the same content The code is as follows:Copy code $ A = "ABC ";$ B = & $;Echo $ a; // output here: ABCEcho $ B; // output here: ABC$ B = "EFG ";Echo $ a; // Here, the

ObjectiveThe following part of the topic from the network, the author gathered here, not only to consolidate themselves, but also hope to help the same needs of people! The reference answers are written by the author, there are questions or mistakes,

1. Describe the design patterns commonly used in your project. What are their pros and cons?The common design patterns are: agents, observers, and Singleton.(1) Singleton: It is used to restrict the creation of a class to only one object. The

The first is a common small problem: arc (Auto Reference counting) compatible with non-arc files (non-arc will have similar error alerts: #error Jsonkit does not supported Objective-c Automatic Reference counting (ARC), you need to add the key

is the class of the basic article objective-c multiple inheritance? Can I use multiple protocols?It is not possible to multiply inheritance, you can use multiple protocols.What mechanism does OBJC use to manage object memory? MRC Manual

One. Memory management includes memory allocation and memory cleanup1. Scope of memory management : People and objects inheriting from the NSObject class need to be memory-managed, any object of non-object type (base data type such as int char float

The main content of this article: The nature of Arc Opening and closing of Arc The arc modifier ARC and Block Arc and toll-free bridging The nature of Arc ARC is the compiler (time) attribute, not the runtime

This article comes from my personal arc learning note, which aims to summarize the key points of the Automatic Reference counting, automatic reference counting technology for iOS development in a concise way, so it doesn't involve all the details.

This article turns from http://blog.chinaunix.net/uid-20608849-id-360294.htmlwhen I write a program, I will encounter this annoyance: a project may have many applications, and a new application will be all the makefile to rewrite, although you can

Unity3d interface is not complex, the layout of the interface can also be changed through the Layouts drop-down list, the following is a simple introduction.1. Scene panel : The leftmost upper half, the panel is the Unity3d edit panel, used to place

Description There are three servers, the MONGODB database has been installed, the specific information as follows: MongoDB version: mongodb-linux-x86_64-2.6.11 MongoDB installation directory:/usr/local/mongodb

Simple additions and deletions to check the data Specify the display in the query results or do not display a field For example, we want to find all the data in the lessons collection, but we don't want to include the Slides field in the return

MongoDB 3.0 Security Permission access controlMongoDB 3.0 access control has changed a lot, you need to pay attention to this parameter authenticationmechanisms. To use the 2.6 version, I directly specify the following

About Paddingfactor always feel very iffy. I don't know what unit this value is, like displaying 1 or 1.4. > Db.test.stats (){"NS": "Test.test","Count": 6,"Size": 272,"Avgobjsize": 45.333333333333336,"Storagesize": 4096,"Numextents": 1,"Nindexes": 1

A long time ago, setting up a wireless network did not work, now make up for the holiday. I'm using Ubuntu 7.10. The X driver must be installed correctly. The relationship between X programs: Ifconfig, Iwconfig, IP, route, wpa_supplicant