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• distributed database https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database Unlike parallel systems, in which the processors are tightly coupled and constitute a single database system, a distributed database system consists of loosely-coupled sites that share no physical components. 1 https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database System administrators can distribute collections of data (e.g. in a database) across multiple physical locations. A distributed database can reside on network servers on the Internet, on corporate intranets or extranets, or on other company networks. Because they store data across multiple computers, distributed databases can improve performance at end-user worksites by allowing transactions to be processed on many machines, instead of being limited to one. 1 https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database 1 Two processes ensure that the distributed databases remain up-to-date and current: replication and duplication. https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database Replication involves using specialized software that looks for changes in the distributive database. Once the changes have been identified, the replication process makes all the databases look the same. The replication process can be complex and time-consuming depending on the size and number of the distributed databases. This process can also require a lot of time and computer resources. 1 https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database 1 Besides distributed database replication and fragmentation, there are many other distributed database design technologies. For example, local autonomy, synchronous and asynchronous distributed database technologies. These technologies' implementation can and does depend on the needs of the business and the sensitivity/confidentiality of the data stored in the database, and hence the price the business is willing to spend on ensuring data security, consistency and integrity. https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database 1 When discussing access to distributed databases, Microsoft favors the term distributed query, which it defines in protocol-specific manner as "[a]ny SELECT, INSERT, UPDATE, or DELETE statement that references tables and rowsets from one or more external OLE DB data sources". Oracle provides a more language-centric view in which distributed queries and distributed transactions form part of distributed SQL. https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database - Architecture 1 A database user accesses the distributed database through: https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database - Architecture 1 A homogeneous distributed database has identical software and hardware running all databases instances, and may appear through a single interface as if it were a single database. A heterogeneous distributed database may have different hardware, operating systems, database management systems, and even data models for different databases. https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database - Homogeneous DDBMS 1 In a homogeneous distributed database all sites have identical software and are aware of each other and agree to cooperate in processing user requests. Each site surrenders part of its autonomy in terms of right to change schema or software. A homogeneous DDBMS appears to the user as a single system. The homogeneous system is much easier to design and manage. The following conditions must be satisfied for homogeneous database: https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database - Heterogeneous DDBMS 1 In a heterogeneous distributed database, different sites may use different schema and software https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database - Important considerations Care with a distributed database must be taken to ensure the following: 1 https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database - Important considerations 1 There are two principal approaches to store a relation r in a distributed database system: https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database - Advantages 1 Improved performance — data is located near the site of greatest demand, and the database systems themselves are parallelized, allowing load on the databases to be balanced among servers. (A high load on one module of the database won't affect other modules of the database in a distributed database) https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database - Advantages 1 Modularity — systems can be modified, added and removed from the distributed database without affecting other modules (systems) https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database - Disadvantages 1 Difficult to maintain integrity — but in a distributed database, enforcing integrity over a network may require too much of the network's resources to be feasible https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database - Disadvantages 1 Inexperience — distributed databases are difficult to work with, and in such a young field there is not much readily available experience in "proper" practice https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database - Disadvantages Database design more complex — In addition to traditional database design challenges, the design of a distributed database has to consider fragmentation of data, allocation of fragments to specific sites and data replication 1 https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database management system 1 Unlike parallel systems, in which the processors are tightly coupled and constitute a single database system, a distributed database system consists of loosely-coupled sites that share no physical components. https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database management system # Replication involves using specialized software that looks for changes in the distributive database. Once the changes have been identified, the replication process makes all the databases look the same. The replication process can be complex and time-consuming depending on the size and number of the distributed databases. This process can also require a lot of time and computer resources. 1 https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database management system 1 When discussing access to distributed databases, Microsoft favors the term 'distributed query', which it defines in protocol-specific manner as [a]ny SELECT, INSERT, UPDATE, or DELETE statement that references tables and rowsets from one or more external OLE DB data sources. https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database management system - Architecture 1 A 'homogeneous distributed database' has identical software and hardware running all databases instances, and may appear through a single interface as if it were a single database. A 'heterogeneous distributed database' may have different hardware, Operating Systems, database management systems, and even data models for different databases. https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database management system - Heterogeneous DDBMS 1 In a heterogeneous distributed database, different sites may use different schema and software https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database management system - Advantages * Improved performance — data is located near the site of greatest demand, and the database systems themselves are parallelized, allowing load on the databases to be balanced among servers. (A high load on one module of the database won't affect other modules of the database in a distributed database) 1 https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database management system - Advantages 1 * Modularity — systems can be modified, added and removed from the distributed database without affecting other modules (systems) https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database management system - Disadvantages 1 * Difficult to maintain integrity — but in a distributed database, enforcing integrity over a network may require too much of the network's resources to be feasible https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database management system - Disadvantages 1 * Inexperience — distributed databases are difficult to work with, and in such a young field there is not much readily available experience in proper practice https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed database management system - Disadvantages * Database design more complex — In addition to traditional database design challenges, the design of a distributed database has to consider fragmentation of data, allocation of fragments to specific sites and data replication 1 https://store.theartofservice.com/the-distributed-database-toolkit.html INGRES - Distributed databases Ingres provides a distributed database system via the IngresSTAR server. 1 https://store.theartofservice.com/the-distributed-database-toolkit.html INGRES - Distributed databases 1 A database must be created as distributed by suffixing the database name with the /star service class. Once they have been created, the tables, views and procedures from other databases may be registered within the distributed database. The distributed database may also have its own tables, views and procedures. https://store.theartofservice.com/the-distributed-database-toolkit.html INGRES - Distributed databases 1 The IngresNET server allows the source databases to be on any other Ingres installation as well as on the installation which holds the distributed database. The IngresBRIDGE server allows the source databases to be non-Ingres databases as well. https://store.theartofservice.com/the-distributed-database-toolkit.html INGRES - Distributed databases 1 User access to the distributed database is exactly as per regular databases. User grants to the registered tables and views are determined by the database from which they are registered. https://store.theartofservice.com/the-distributed-database-toolkit.html Distributed data store - Distributed databases 1 Distributed databases are usually nonrelational databases that make a quick access to data over a large number of nodes possible. Some distributed databases expose rich query abilities while others are limited to a key-value store semantics. Examples of limited distributed databases are Google's BigTable, which is much more than a distributed file system or a peer-to-peer network, Amazon.com|Amazon's Dynamo (storage system)|Dynamo https://store.theartofservice.com/the-distributed-database-toolkit.html For More Information, Visit: • https://store.theartofservice.co m/the-distributed-databasetoolkit.html The Art of Service https://store.theartofservice.com