Key-Value Store databaseTemporary: as memcached. The temporary key-value database stores the data in memory, which in two cases results in the loss of data, the first is the power outage, but the data content exceeds the memory size. The benefits of this treatment are very fast.Permanent type: such as Tokyo Tyrant, flare and RomaThe two are both types: Redis. Redis first data in memory, and then meet certain conditions (the default is 15 minutes more than 1 times, 5 minutes more than 10, 11 minu
What is nosql?
Nosql (nosql = not only SQL) means not only SQL expansion, but also non-relational databases.
With the rise of Internet Web websites, traditional relational databases are dealing with Web websites, especially ultra-large-scale and high-concurrency SNS type
Tags: introduction to NoSQL databasesFirst, IntroductionNoSQL (not only SQL), refers to the non-relational database. With the rise of internet web2.0 website, the traditional relational database in coping with web2.0 website, especially the web2.0 pure dynamic website of ultra-large-scale and high-concurrency SNS type, has been unable to overcome, exposing a lot of difficult problems, and the non-relational
Just a few years ago, MySQL was recognized as the king of the open source database field. However, as nosql grew at a compound growth rate of 82% per year, MySQL is facing the risk of being eliminated by nosql in the Web application market.
The migration to nosql has not only become a concern for the development trend of the IT industry, but also allows people to
that if the machine restarts the data it will be lost. Persistence allows data to be stored on persistent storage media such as disks.2. Document-oriented database. This database is characterized by the ability to store data directly without the need to define a table structure, while supporting complex query conditions. MongoDB belongs to this type.3, column-oriented database. The main is compared with the line-oriented comparison (now the mainstream database, such as relational database is li
The top 10 SQL and NoSQL databases in the latest statistics, and nosql databases in the latest statistics
This ranking is based on the ranking of DB Engines, which analyzes the popularity of 200 different databases on the market. The Top 10
cluster status synchronization (such as cluster member information dissemination. Although the introduction of a database monitoring and synchronization plan coordinator can solve this problem, decentralized databases can provide better fault tolerance. The main approach to decentralization is to use a well-designed infectious Protocol [7], which is relatively simple but provides a good convergence time an
relational databases and NoSQL databases what is NoSQLHave you ever heard of "NoSQL"? In recent years, this word has been of great concern. To see the word "NoSQL," you might mistakenly think it was "no! SQL "abbreviation, and deeply outraged:" How can SQL be unnecessary? "
data can be written to a node as soon as possible without being delayed by the network transmission. The disadvantage is that consistency is not always guaranteed, and a small amount of data may be lost in the event of a failure.
The RDBMS adheres to the acid principle, and NoSQL has the base principle , which conforms to the CP in the CAP, which conforms to the AP in the CAP (that is, the former sacrifices availability, the latter sacrifices con
NoSQL databases: data consistency, nosql Database ConsistencyNoSQL Database: Data ConsistencyRead consistency
High ConsistencyAccess any node in the cluster at any time, and the data obtained is consistent;
User consistency is consistent with the data obtained during cluster access for the same user;Solve user consistency: Use a sticky session to bind the sess
not supported. this has the advantage of NoSQL as well as its drawbacks, after all, the business is still needed in many situations, and the acid feature allows the system to perform accurately in the event of an outage.ACID, which is an abbreviation for the four basic elements that the database transaction performs correctly. Contains: atomicity (atomicity), consistency (consistency), isolation (isolation), persistence (durability). A support transa
Tags: relational data table NoSQL database L database Combat div operation Field
Why NoSQL is produced:
The fact that relational databases are not good at doing so is the reason why NoSQL is Born:
Large number of data write operationsThe book is written "large amounts of data write operations", I unde
Recently I am reading nosql. A major advantage of nosql over relational databases is high availability. Therefore, some questions are raised:
Why does nosql achieve high availability while relational databases suffer from criticism in this regard?
Relational Database
[TechTarget Chinese original] Q: I am studying various types of database architectures. Can you tell me the security of non-SQL databases (NoSQL) and mainstream commercial relational databases?
For a database that stores information securely, it must provide confidentiality, integrity, and availability (CIA ). When necessary, data must be available (availability
premise, the overhead of data update is very small (the same field basically only has one)
3. complex queries such as Join operations can be performed (Join operations cannot be performed between different servers)
4. There are many practical achievements and professional technical information (mature technologies)
5. All data is expressed in the binary representation of rows and columns, which makes it easier to understand and understand.
Lack of relational
relational database.
Relational databases are widely used for complex processing such as transaction processing and JOIN. Comparatively, NoSQL databases are only applied in specific fields and basically do not carry out complex processing, but they just make up for the shortcomings of the previously listed relational databas
models. For the following information, see the Emil Eifrem blog and NoSQL database description.
Document Database
Inheritance: inspired by Lotus Notes.
Data Model: document summary, including key-value summary.
Instance: CouchDB, MongoDB
Advantages: Data Modeling is natural, programmers are easy to use, the development process is short, the webpage mode is compatible, and CRUD (short for adding, querying, updating, and deleting) is easy to achieve ).
distributed algorithms and ideas in NoSQL databases. The article is very long and translated and contributed by @ juliashine. Thank you for your sharing spirit!
Translator's introduction: Juliashine has been an engineer for many years. He is now working on massive data processing and analysis, focusing on the Hadoop and NoSQ
reconciliation and Flow Control for anti-entropy protocols
S. Ranganathan et al gossip-style Failure Detection and distributed Consensus for scalable heterogeneous Clusters
http://www.slideshare.net/kakugawa/distributed-counters-in-cassandra-cassandra-summit-2010
N. Hayashibara, X. Defago, R. Yared, T. Katayama. The Phi accrual Failure Detector
M.J Fischer, N.a Lynch, and M.S. Paterson. Impossibility of distributed Consensus with one faulty Process
N. Hayashibara, A. Cherif, T. K
.
Relational databases create more problems when dealing with these trends. This leads to the emergence of a large number of different techniques to address specific aspects of these problems, which can interact with or replace existing RDBMS-also known as hybrid persistence (Polyglot persistence). Database substitutes are not new, they have been in the form of object Databases (OODBMS), hierarchical
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
info-contact@alibabacloud.com
and provide relevant evidence. A staff member will contact you within 5 working days.