What is a distributed database? This article will introduce you to the distributed database and understand the advantages and disadvantages of using it. I hope it will be helpful to you.
What is a distributed database?
Distributed databases are multiple interconnected databases. They are usually located on multiple servers but communicate with each other to achieve common goals; through a distributed database management system (DDBMS ) for management.
Distributed database provides the advantages of distributed computing for the field of database management. Basically, we can define a distributed database as a collection of multiple related databases distributed over a computer network.
Advantages of distributed database
1. Can manage data with different transparency
Ideally, a database should be distribution transparent, hiding the details of where each file is physically stored in the system. In a distributed database system, basically the following types of transparency can be used:
● Network transparency: This basically refers to the freedom that users get from the operational details of the network. They are of two types: positional and named transparency.
● Replication Transparency: It basically makes users unaware of the existence of replicas because we know that data replicas may be stored in multiple sites for better availability and reliability.
● Fragment Transparency: It basically makes the user unaware of the existence of fragments, which may be vertical fragments or horizontal fragments.
2. Improve reliability and availability
Reliability is basically defined as the probability of a system running at a specific time, while availability is defined as the continuous availability of a system over a period of time The probability. When data and DBMS software are distributed across multiple sites, one site may fail while other sites continue to function and we cannot access only the data present in the failed site, which basically improves reliability and availability.
3. Easier expansion
In a distributed environment, expand the system in terms of adding more data, increasing the database size or adding more data, increasing the database size Or it's much easier to add more processors.
4. Improved performance
By breaking the query into multiple subqueries that are essentially executed in parallel, we can implement the query by executing multiple queries at different sites Inter- and intra-query parallelism, which essentially improves performance.
Disadvantages of distributed databases
1. Complexity, distributed database architecture has higher requirements in design, troubleshooting and management.
2. Many complex routines must be developed to ensure that data synchronization works properly.
3. There will be a delay between the master data and the satellite data footprint, with many reports generated by the satellite database being different from the master data. This issue must be evaluated during the design of the synchronization frequency.
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