relational database advantages and disadvantages

First, why do you want to create an index (advantage)?This is because creating an index can greatly improve the performance of the system.First, by creating a unique index, you can guarantee the uniqueness of each row of data in a database table.Second, it can greatly speed up the retrieval of data, which is the main reason for creating indexes.Thirdly, the connection between tables and tables can be accelerated, particularly in terms of achieving ref

Advantages and disadvantages of mybatis and mybatis Advantages: 1. Easy to use and master. 2. SQL is written in xml to facilitate unified management and optimization. 3. Remove the coupling between SQL and program code. 4. Provides ing labels and supports orm field ing between objects and databases. 5. Provides object link ing labels and supports object link crea

procedure. The disadvantage of stored procedures 1: Debugging trouble, but with PL/SQL Developer debugging is very convenient! 　　compensate for this shortcoming. 2: Porting issues, database-side code is of course related to the database. 　　However, if you are doing engineering projects, there is basically no transplant problem. 3: Recompile the problem because the backend code is compiled before it is run,

balancer software, which is implemented at the software level, so the cost is very low. Currently, the website architecture is generally reasonable and popular: The Web Front-end uses nginx/haproxy + keepalived as the Load balancer, And the backend uses the MySQL database for master-slave and read-write separation, use the LVS + keepalived architecture. Of course, you must develop a scheme based on the specific needs of the project.Next we will talk

There is not much understanding and use of XML. This is a summary of the advantages and disadvantages of XML in the video of a lecture. Sorry! I will continue to learn about XML. Advantage: scalabilityAlthough XML has many other characteristics, its scalability is self-evident. It can be said that "nothing is part of XML extension ". In business design, the scalability of the business is very related to th

When I was an interviewer at SitePoint, I was certain to ask: What do you think are the advantages and disadvantages of PHP code? This problem gives me a general idea of the type of programmer the applicant is, rather than simply understanding his understanding of PHP functions (this Zend PHP certification is doing well, yahoo's PHP programmer interview questions also fall into this category ). What's impor

What are the advantages and disadvantages of R language?2015-05-27 programmer Big Data Small analysis R, not just a languageThis article is originally contained in "Programmer" magazine 2010 8th, because of the limitation of space, has been limited, here is the full text.工欲善其事, its prerequisite, as an engineer in the forefront of the IT world, C + +, Java, Perl, Python, Ruby, PHP, JavaScript, Erlang, and s

What are the advantages and disadvantages of iOS-Swift compared with Objective-C, Swift is a new development language released by Apple at the 2014 WWDC (Apple Developer Conference). It can run together with Objective-C on Mac OS and iOS platforms, it is used to build applications based on the Apple platform. It is an easy-to-learn and easy-to-use programming language, and it is also the first system progra

Advantages and disadvantages of mysq index Establishment Advantages and necessity of index creation: 1. By creating a unique index, You can ensure the uniqueness of each row of data in the database table; Second, it can greatly speed up data retrieval, which is also the main reason for creating indexes; Third, it can a

where you need to pull data from multiple data sources and then process it.(1) Serial data acquisition, which is our general solution, take PHP as an exampleIf you need 1S for both profile and timeline operations, then serial acquisition requires 2S.(2) Nodejs non-blocking I/O, transmit/listen events to control the execution processNodejs encountered I/O event will create a thread to execute, and then the main thread will continue to execute, therefore, take the action of profile to trigger an

inappropriate: A program that is not suitable to do time- efficient (fast algorithm) or very flexible space performance (memory is released immediately), because of intermediate language and compilation process, than c/c++native type of language will be slower , the memory of the active recovery is difficult to release the unnecessary memory immediately, do not use the inline function and destructor (not recommended).Limited support beyond the 2.Windows platform: mono is not mature enough to us

is called recompile )". Both compilation and recompilation of execution plans consume resources.If the execution plan can be reused, SQLSERVER does not need to execute the above process to speed up the execution of commands. This is what I mean when I mention the database reuse execution plan in many statement optimization articles. Advantages and disadvantages

complex applications. The monolithic architecture is more suitable for lightweight, simple applications. If you use it to develop complex applications, it's really bad. The MicroServices architecture model can be used to build complex applications, and of course, this architectural model has its own shortcomings and challenges. In a subsequent blog, I'll delve into the microservices architecture pattern and discuss strategies such as service discovery, service deployment choices, and how to bre

I. Why should I create an index (advantage )? Creating indexes can greatly improve the system performance. First, By creating a unique index, You can ensure the uniqueness of each row of data in the database table. Second, This can greatly speed up data retrieval, which is also the main reason for creating an index. Third, It can accelerate the connection between tables, especially for Data Reference integrity. Fourth, When you use grouping and so

Since I have not been familiar with Oracle, I have not answered this question. I have checked the information and summarized it as follows. I have the opportunity to study oracle in the future. I don't know how the written test is. I hope God didn't go to WC. Advantages and disadvantages of hot backup and cold backupAdvantages of Hot Backup: 1. Data can be backed up at the tablespace or data file level. T

This article mainly introduces the advantages and disadvantages of SQL Server, Mysql, Oracle Three kinds of databases, the need for friends can refer to the followingfirst, SQL ServerAdvantages:Ease of use, scalability for distributed organizations, data warehousing for decision support, integration with many other server software, and good price/performance ratio;Provides flexibility for data management an

Sing Xing interprets the advantages and disadvantages of mysql stored procedures, Xin Xing mysql Common SQL statements must be compiled and executed before execution. stored procedures are a set of SQL statements to complete specific functions, it is directly compiled and stored in the database. You can call the stored procedure by specifying the name of the stor

Excellent php code should be structured; excellent PHP code should be standardized; excellent PHP code should be adaptive; excellent PHP code should be safe ...... When I was an interviewer at SitePoint, I was certain to ask: what do you think are the advantages and disadvantages of PHP code? This problem gives me a general idea of the type of programmer the applicant is, rather than simply understanding hi

Advantages and disadvantages of paradigm and anti-paradigm When designing databases, there are paradigm and anti-paradigm considerations. The following is a summary. Advantages of paradigm: 1) more rapid updates of the paradigm-based database; 2) After normalization, there is only a small amount of duplicate da

In the design of the database, there are paradigms and anti-paradigm of stress, summarized below. Advantages of the paradigm:1) The normalized database is updated more quickly;2) After normalization, only a small number of duplicate data, only need to modify less data;3) The normalized table is smaller and can be executed in memory;4) Less redundant data, requiri