disadvantages of mongodb

clusters K is an input parameter, the inappropriate k value may return poor results? application areas: image segmentation, analysis of commodity similarity to classify commodities, analysis of the company's customer classification to use different business strategiesStatistical learning--em? Core idea: maximize expectations with e-steps and M-Steps? Algorithm Advantages: Simple and stable? algorithm disadvantage: iterative speed is slow, many times, easy to fall into the local optimal? applica

any time, do not require the developer to do the precise processing, so, excessive use of the session variable will cause the code unreadable and poorly maintained.Although "You can use the session variable directly at any time you want to use it, rather than declaring it in advance, this approach is similar to the use of variables in VB." After you have finished using it, you do not have to consider releasing it, as it will automatically release ". But, "who" thinks of it? What does the variab

Now many websites have used the div+css to layout the webpage structure, the advantage is the speed is fast, may the negative influence, see below analysis Front-End time to write a "use of CSS framework for efficient site development", a lot of friends asked me related questions. Very early 5key in the company for the framework of CSS frameworks, but also to many friends of the proposed CSS framework. The effect is very obvious. Of course, the CSS framework has advantages and

This blog is reproduced from a blog post, introduced Gan (generative adversarial Networks) that is the principle of generative warfare network and Gan's advantages and disadvantages of analysis and the development of GAN Network research. Here is the content. 1. Build Model 1.1 Overview Machine learning methods can be divided into generation methods (generative approach) and discriminant methods (discriminative approach), and the models learned are c

Hello everyone, today to share with you the pros and cons of free space problem. Now a lot of domain name business host space vendors in vigorously promote the free things. So how much do you know about the free stuff? Everyone knows you can get it without money. But you only see the surface, do not see the inner side, think about it, the General people will give you free of what the concept, others can not lose money to you on the free throw, for you to use it. Once heard an old-timer said a wo

the client, the use of idle client capacity to deal with, reduce the burden of server and bandwidth, save space and broadband rental costs. and reduce the burden on the server, the principle of Ajax is "on-demand data", can minimize redundant requests, and respond to the burden on the server. 4, based on standardized and widely supported technology, do not need to download plug-ins or small programs. 7, the disadvantages of Ajax Here's what I'll f

Front-End time to write a "use of CSS framework for efficient site development", a lot of friends asked me related questions. Very early 5key in the company for the framework of CSS frameworks, but also to many friends of the proposed CSS framework. The effect is very obvious. Of course, the CSS framework has advantages and disadvantages, and recently read some related articles. Some thoughts, share with you. The benefits of CSS frameworks: 1, the dev

advantages and disadvantages of sequential tables and linked list storage 1. Sequential table Storage Principle: Sequential table storage is to put data elements into a contiguous memory storage space, access efficiency, fast. But you can't increase the length dynamically. Advantages: Efficient access, direct storage via subscript Cons: 1. Insertions and deletions are slow, 2. Length cannot be increased For example: when inserting or deleting an

Tags: input parameters data Types mapping relationships overrides res Limitations Different decisions advantage JDBC: We normally use JDBC for programming, which takes a few steps: 1, using JDBC programming to connect to a database, registering drive and database information NBSP;2, operating connection, Open Statement Object NBSP;3, execute SQL from statement object, return result to ResultSet object 4, use resultset to read data, then translate code into specific Pojo object NBS

Label: Why do you want to create an index? This is because creating an index can greatly improve the performance of the system.First, by creating a unique index. To ensure that each row of unique data is in a database table.Second, high-speed data retrieval can be greatly accelerated, which is the most basic reason to create an index.Third. This is particularly relevant in terms of achieving the data's textual integrity.The same can significantly reduce the time of grouping and sorting in querie

Mongodb advanced 2: mongodb aggregation and mongodb advanced AggregationIn the previous article we talked about mongodb's advanced query: http://blog.csdn.net/stronglyh/article/details/46817789 This article introduces mongodb aggregation. I. mongodb has many aggregation fram

Tags: index XA requires action set x86 read and Write permissions God BPAinstallation :1 Download Linux installation package 2 on the official website in Linux decompression 3 will unzip the directory MV to the specified installation directoryMV mongodb-linux-x86_64-rhel70-3.6. 5//usr/local/mongodb4 CD to the bin directory, execute the following command to add the environment variable:Export path= $PATH:/usr/local/

Let's talk about the advantages and disadvantages of Ajax. Ajax, short for Asynchronous Javascript and XML, is a dynamic WEB application development technology that enriches the user experience. Even WEB applications developed with Ajax can experience desktop applications. Of course, like other technologies, Ajax also has its own advantages and disadvantages. UseAdvantages of Ajax 1. Improve user experience

Tags: redis disadvantages advantages I recently used redis in my project. So I am looking at the redis source code. Next I plan to introduce the overall situation of redis and gradually write the redis source code functions. However, before doing anything, you should consider its advantages and disadvantages. Therefore, write the advantages and disadvantages of r