Cloud database

{{short description|Database running on a cloud computing platform}} A '''cloud database''' is a database that typically runs on a cloud computing platform, with access provided as a service. There are two common deployment models: users can run databases on the cloud independently, using a virtual machine image, or they can purchase access to a database service maintained by a cloud database provider. Cloud databases may use either a relational SQL or a NoSQL data model.

Database services handle scalability and high availability, while making the underlying software stack transparent to users.<ref>{{Cite book|last1=Hwang|first1=G.|last2=Fu|first2=S.|title=2016 16th IEEE/ACM International Symposium on Cluster, Cloud and Grid Computing (CCGrid) |chapter=Proof of Violation for Trust and Accountability of Cloud Database Systems |date=May 2016|pages=425–433|doi=10.1109/CCGrid.2016.27|isbn=978-1-5090-2453-7 |s2cid=18373753 }}</ref>

== Deployment models == There are two primary methods to run a database on a cloud platform:

; Virtual machine image: Cloud platforms allow users to purchase virtual machine instances for a limited time, on which a database can be run. Users can upload their own machine image with a database installed or use ready-made machine images that include an optimized installation of a database.<ref name=":2">{{Cite book |last=Chao |first=Lee |title=Cloud database development and management |date=2014 |publisher=Taylor & Francis |isbn=978-1-4665-6506-7 |location=Boca Raton |oclc=857081580}}</ref> ; ; Database-as-a-service (DBaaS): With a database as a service (DBaaS) model, users pay a cloud provider for database services and computing resources, which may reduce the operational overhead needed to develop and manage databases.<ref name=":2" /> Users are provided with tools to create and manage database instances, as well as to manage database users. Some cloud providers also offer tools for managing database structures and data.<ref name=":1">{{Cite book |last=McHaney |first=Roger |title=Cloud technologies: an overview of cloud computing technologies for managers |date=2021 |isbn=978-1-119-76951-4 |location=Hoboken, NJ |oclc=1196822611}}</ref> Many cloud providers offer both relational (e.g., Amazon RDS, SQL Server) and NoSQL (e.g., MongoDB, Amazon DynamoDB) databases.<ref name=":1" /> DBaaS is a type of software as a service (SaaS).

=== Architecture and common characteristics === * Most database services offer web-based consoles that end users can use to provision and configure database instances. * Database services routinely include a database-manager component that manages the underlying database instances using a service API. The API is exposed to end users and permits them to perform maintenance and scaling operations on their database instances. * The underlying software stack typically includes the operating system, the database, and third-party software used to manage the database. The service provider is responsible for installing, patching, and updating the underlying software stack, as well as ensuring the overall health and performance of the database. * Scalability features differ between vendors—some offer auto-scaling, others allow users to scale resources via an API but do not scale automatically.<ref name=":2" /> * Service providers typically commit to a defined level of high availability (e.g., 99.9% or 99.99%). This is achieved through techniques such as data replication and automatic failover to standby instances.<ref>{{Cite journal |last=Sakr |first=Sherif |date=June 2014 |title=Cloud-hosted databases: technologies, challenges and opportunities |url=http://link.springer.com/10.1007/s10586-013-0290-7 |journal=Cluster Computing |language=en |volume=17 |issue=2 |pages=487–502 |doi=10.1007/s10586-013-0290-7 |s2cid=254370104 |issn=1386-7857|url-access=subscription }}</ref>

== Data model == The design and development of typical systems often use data management and relational databases as key building blocks. Advanced queries expressed in SQL work well with the strict relationships imposed by relational databases. However, relational database technology was not originally designed for use over distributed systems. This limitation has been addressed through clustering enhancements, although some fundamental operations—such as data synchronization—still require complex and expensive protocols.<ref>A. Anjomshoaa and A. Tjoa, [http://dl.acm.org/citation.cfm?id=2095539&CFID=676853031&CFTOKEN=59417535 "How the cloud computing paradigm could shape the future of enterprise information processing"], Proceedings of the 13th International Conference on Information Integration and Web-based Applications and Services - iiWAS'11, pp. 7-10, 2011.</ref>

Modern relational databases can exhibit poor performance on data-intensive systems. As a result, the NoSQL paradigm has been adopted within database management systems for cloud-based systems.<ref>S. Cass, "Designing for the Cloud", MIT Technology Review, 2009. [Online]. Available: https://www.technologyreview.com/s/414090/designing-for-the-cloud/. Retrieved 2016-10-04.</ref> NoSQL storage does not require fixed table schemas, and join operations are typically avoided. NoSQL databases have been shown to provide efficient horizontal scalability, high performance, and ease of integration into cloud applications.<ref>"NoSQL", Wikipedia, 2016. Retrieved 2016-10-04.</ref> Additionally, data models that rely on simplified relay algorithms have been employed in data-intensive cloud mapping applications specific to virtual frameworks.<ref>{{cite journal |last1=Modi |first1=A |title=Live migration of virtual machines with their local persistent storage in a data intensive cloud |journal=International Journal of High Performance Computing and Networking |date=2017 |volume=10 |issue=1|page=134 |article-number=83213 |doi=10.1504/IJHPCN.2017.083213 }}</ref>

It is also important to differentiate between cloud databases which are relational (SQL) and those that are non-relational (NoSQL).<ref>https://docs.microsoft.com/en-us/azure/architecture/data-guide/big-data/non-relational-data Article in 'Microsoft Azure'</ref> ; SQL databases: SQL databases can run in the cloud either on virtual machines or as a managed service, depending on the vendor. While SQL databases are generally easy to scale vertically, horizontal scalability presents a greater challenge. ; ; NoSQL databases: NoSQL databases are designed to service heavy read/write loads and can scale up and down easily,<ref name="Agrawal2008">{{cite journal|author = Agrawal, Rakesh |title = The Claremont report on database research |journal = SIGMOD Record |volume = 37 |number = 3 |year = 2008 |issn = 0163-5808 |pages = 9–19 |doi = 10.1145/1462571.1462573 |url= http://db.cs.berkeley.edu/claremont/claremontreport08.pdf |display-authors=etal|citeseerx = 10.1.1.211.5963 |s2cid = 666280 }}</ref> making them well suited to cloud environments. However, many contemporary applications are built around a relational (SQL) data model, so adopting NoSQL databases often requires significant changes to application code.<ref>Ken North, "[http://drdobbs.com/blogs/database/228701075 SQL, NoSQL or SomeSQL?]", Dr. Dobb's, Retrieved 2011-11-9.</ref> : : Some SQL databases have developed NoSQL capabilities, including JSON, binary JSON (e.g. BSON or similar variants), and key-value store data types. : : Multi-model databases combine relational and non-relational capabilities, providing a standard SQL interface to users and applications. Native multi-model databases support multiple data models with a single core, facilitating their use in applications built around SQL.

== Vendors == The following table lists notable database vendors that offer cloud database services, classified by deployment model—machine image or database as a service—and by data model (SQL or NoSQL).

{| class="wikitable" style="text-align: center; width: 75%;" |+ Cloud database vendors by deployment and data model |- ! scope="col" | ! scope="col" | Virtual Machine Deployment ! scope="col" | Database as a Service |- ! scope="row" | SQL Data Model | * EDB Postgres Advanced Server * IBM Db2<ref>[http://www.ibm.com/developerworks/data/tutorials/dm-1001db2amazonec2/index.html Deploy your database applications and projects on the cloud], IBM.com, Retrieved 2011-9-1</ref> * Ingres (database)<ref>Chris Kanaracus, "[http://www.infoworld.com/d/data-center/ingres-rolls-out-cloud-database-offerings-965 Ingres rolls out cloud database offerings]", ''InfoWorld'', Retrieved 2011-8-28.</ref> * MariaDB<ref>"[http://phx.corporate-ir.net/phoenix.zhtml?c=176060&p=irol-newsArticle&ID=2095051 Amazon Web Services Announces Two New Database Services – AWS Database Migration Service and Amazon RDS for MariaDB] {{Webarchive|url=https://web.archive.org/web/20170601175022/http://phx.corporate-ir.net/phoenix.zhtml?c=176060&p=irol-newsArticle&ID=2095051 |date=2017-06-01}}, Amazon Press Releases, retrieved 2015-11-17</ref><ref>"[https://azure.microsoft.com/en-us/marketplace/partners/mariadb/cluster-maxscale/ MariaDB Enterprise Cluster + MariaDB MaxScale] {{Webarchive|url=https://web.archive.org/web/20161204101728/https://azure.microsoft.com/en-us/marketplace/partners/mariadb/cluster-maxscale/ |date=2016-12-04}}, Microsoft Azure, retrieved 2015-11-17</ref> * MySQL<ref>"[http://aws.amazon.com/articles/1663 Running MySQL on Amazon EC2 with EBS (Elastic Block Store)], Amazon Web Services, retrieved 2011-11-20</ref> * NuoDB<ref>Swoyer, Stephen. [http://tdwi.org/articles/2012/11/13/nuodb-cloud-database.aspx "NuoDB: A Database for the Cloud."] TDWI. Nov. 13, 2012. Retrieved Nov. 26, 2012</ref> * Oracle Database<ref name="oracle-aws">[http://aws.amazon.com/amis/Oracle/3647 Amazon Machine Images - Oracle Database 11g Release 2 (11.2.0.1) Enterprise Edition - 64 Bit] {{webarchive |url=https://web.archive.org/web/20111016213708/http://aws.amazon.com/amis/Oracle/3647 |date=2011-10-16}}, Amazon Web Services, Retrieved 2011-11-9.</ref><ref>"[http://www.oracle.com/technetwork/topics/cloud/database-cloud-openworld08-168208.pdf Oracle Database in the Cloud]", Oracle.com, Retrieved 2011-11-9.</ref> * PostgreSQL<ref>Chris Kanaracus, "[https://www.pcworld.com/article/238775/enterprisedb_adding_new_cloud_option_for_postgresql_database.html EnterpriseDB Adding New Cloud Option for PostgreSQL Database]", ''PCWorld'', retrieved 2011-8-28</ref> * SAP HANA<ref>{{cite web |url=https://aws.amazon.com/sap/solutions/saphana/ |title=AWS {{!}} SAP HANA |work=Amazon Web Services, Inc. |access-date=2016-07-07}}</ref><ref>{{cite web |url=https://azure.microsoft.com/en-us/campaigns/sap/ |title=SAP Solutions |work=Microsoft Azure |access-date=2016-07-07}}</ref><ref>{{cite web |url=https://hana.sap.com/implementation/deployment/cloud/hana-enterprise-cloud.html |title=SAP HANA Enterprise Cloud |work=hana.sap.com |archive-url=https://web.archive.org/web/20160815002558/https://hana.sap.com/implementation/deployment/cloud/hana-enterprise-cloud.html |archive-date=2016-08-15 }}</ref> * YugabyteDB * TiDB | * Amazon Aurora, MySQL-based service *Amazon Relational Database Service * Clustrix Database as a Service<ref>{{Cite web |url=https://finance.yahoo.com/news/clustrix-enters-rackspace-partner-program-120500944.html |title=Clustrix Enters the Rackspace Partner Program |work=Yahoo! Finance |archive-url=https://web.archive.org/web/20160414015133/http://finance.yahoo.com/news/clustrix-enters-rackspace-partner-program-120500944.html |archive-date=2016-04-14 }}</ref> * CockroachDB-as-a-Service<ref>Tony Baer, "[https://www.zdnet.com/article/cockroach-db-introduces-a-serverless-tier/ Cockroach DB introduces a serverless tier]", ''ZDNet.com'', Retrieved 2021-12-13.</ref> * EnterpriseDB Postgres Plus Cloud Database<ref name=":0">EnterpriseDB#cite note-10</ref> * Google Cloud SQL<ref>{{cite web |url=https://cloud.google.com/sql/ |title=Cloud SQL - MySQL Relational Database Service |access-date=2016-11-28}}</ref> * Heroku PostgreSQL as a Service (shared and dedicated database options)<ref>"[http://blog.heroku.com/archives/2010/11/4/heroku_postgresql/ Announcing Heroku PostgreSQL Database Add-on]", Heroku Blog, Retrieved 2011-11-9.</ref> * Microsoft Azure SQL Database (MS SQL)<ref>Noel Yuhanna, ''[http://www.microsoft.com/presspass/itanalyst/docs/11-02-10SQLAzure.PDF SQL Azure Raises The Bar On Cloud Databases]'', Forrester, Retrieved 2011-11-9.</ref> *Oracle Database Cloud Service<ref>{{cite book |url=https://books.google.com/books?id=m95GAwAAQBAJ&dq=Oracle+Cloud+Database&pg=PA223 |title=Handbook of Research on Cloud Infrastructures for Big Data Analytics |last=Pethuru |first=Raj |date=2014-03-31 |publisher=IGI Global |isbn=9781466658653 |language=en}}</ref> * SkySQL MariaDB * Snowflake Cloud Data Warehouse * Xeround Cloud Database*{{snd}}MySQL front-end (*service no longer available)<ref name="readwriteweb">Klint Finley, [http://www.readwriteweb.com/cloud/2011/01/7-cloud-based-database-service.php "7 Cloud-Based Database Services"] {{webarchive |url=https://web.archive.org/web/20111109084453/http://www.readwriteweb.com/cloud/2011/01/7-cloud-based-database-service.php |date=2011-11-09}}, ''ReadWriteWeb'', Retrieved 2011-11-9.</ref> * YugabyteDB * TiDB |- ! scope="row" | NoSQL Data Model | * Apache Cassandra on Amazon EC2<ref>"[https://wiki.apache.org/cassandra/CloudConfig Setting up Cassandra in the Cloud] {{webarchive |url=https://web.archive.org/web/20151113022557/http://wiki.apache.org/cassandra/CloudConfig |date=2015-11-13}}", Cassandra Wiki, Retrieved 2011-11-10.</ref> or Google Compute Engine<ref>{{cite web |url=https://cloudplatform.googleblog.com/2014/07/click-to-deploy-apache-cassandra-on-google-compute-engine.html |title=Google Cloud Platform Blog: Click to Deploy Apache Cassandra on Google Compute Engine |access-date=2016-11-28}}</ref> * ArangoDB on Amazon EC2, Google Compute or Microsoft Azure<ref>"[https://docs.arangodb.com/3.2/Manual/Deployment/Mesos.html] {{Webarchive|url=https://web.archive.org/web/20190411231949/https://docs.arangodb.com/3.2/Manual/Deployment/Mesos.html|date=2019-04-11}}</ref> *Clusterpoint Database Virtual Box VM<ref>"[http://docs.clusterpoint.com/wiki/Clusterpoint_installation_using_Virtual_Box Clusterpoint Database Virtual Box VM Installation Guide] {{webarchive |url=https://archive.today/20150310161740/http://docs.clusterpoint.com/wiki/Clusterpoint_installation_using_Virtual_Box |date=2015-03-10}}", Clusterpoint, Retrieved 2015-03-08.</ref> * CouchDB on Amazon EC2<ref>"[http://aws.amazon.com/amis/Community/2861 Amazon Machine Images, CouchDB 0.10.x 32 bit Ubuntu]{{Dead link |date=July 2019 |bot=InternetArchiveBot |fix-attempted=yes}}", Amazon Web Services, Retrieved 2011-11-10.</ref> or Google Cloud Platform<ref>{{cite web |url=https://bitnami.com/stack/couchdb/cloud/google |title=CouchDB Cloud Hosting on Google Cloud Platform |access-date=2016-11-28}}</ref> * EDB Postgres Advanced Server * Hadoop on Amazon EC2,<ref>"[http://aws.amazon.com/amis/Community/647 Amazon Machine Image, Hadoop AMI]{{dead link |date=July 2019 |bot=InternetArchiveBot |fix-attempted=yes}}", Amazon Web Services, Retrieved 2011-11-10.</ref> Google Cloud Platform,<ref>{{cite web |url=https://cloud.google.com/dataproc/ |title=Cloud Dataproc: Managed Spark & Managed Hadoop Service |access-date=2016-11-28}}</ref> or Rackspace<ref>["http://www.rackspace.com/blog/cloud-big-data-platform-limited-availability/ Hadoop at Rackspace] {{webarchive |url=https://web.archive.org/web/20140302041422/http://www.rackspace.com/blog/cloud-big-data-platform-limited-availability/ |date=2014-03-02}}", Rackspace Big Data Platforms, Retrieved 2014-02-24.</ref> * MarkLogic on Amazon EC2<ref>{{cite web |url=https://aws.amazon.com/marketplace/pp/B00U36DS6Y/ref=wikipedia_cloud_db |title=MarkLogic Developer 8 (HVM) on AWS Marketplace |work=aws.amazon.com |access-date=2016-03-31}}</ref> or Google Cloud Platform<ref>{{cite web |url=http://www.marklogic.com/wp-content/uploads/2016/09/Flexible-Deployment-Datasheet.pdf |title=Flexible Deployment |host=marklogic.com |access-date=2016-11-28}}</ref> * MongoDB on Amazon EC2,<ref>{{Cite web |title=Install MongoDB on Amazon EC2 — MongoDB Manual |url=https://mongodb-documentation.readthedocs.io/en/latest/ecosystem/tutorial/install-mongodb-on-amazon-ec2.html#gsc.tab=0 |access-date=2026-04-01 |website=mongodb-documentation.readthedocs.io}}</ref> Google Compute Engine or Microsoft Azure, VMware, KVM, and other hypervisors.<ref>{{Cite web |title=Production Notes for Self-Managed Deployments - Database Manual - MongoDB Docs |url=https://www.mongodb.com/docs/manual/administration/production-notes/ |access-date=2026-04-01 |website=www.mongodb.com |language=en}}</ref> * Neo4J on Amazon EC2<ref>"[http://wiki.neo4j.org/content/Neo4j_in_the_Cloud Neo4J in the Cloud] {{webarchive |url=https://web.archive.org/web/20110925234234/http://wiki.neo4j.org/content/Neo4j_in_the_Cloud |date=2011-09-25}}", Neo4J Wiki, Retrieved 2011-11-10.</ref> or Microsoft Azure<ref>"[https://neo4j.com/blog/announcing-neo4j-on-windows-azure/ Announcing Neo4J on Windows Azure]", Neo4J Blog, Retrieved 2011-11-10.</ref> * ScyllaDB on Amazon EC2 or Google Cloud Platform<ref name="computerweekly.com">Adrian Bridgwater, "[https://www.computerweekly.com/blog/Open-Source-Insider/Scyllas-real-time-NoSQL-database-tapped-by-super-app ScyllaDB's real-time NoSQL database tapped by 'super app']", Computerworld, Retrieved 2012-12-27.</ref> * YugabyteDB

| * Amazon DynamoDB * Amazon SimpleDB{{citation needed|date=April 2015}} * Azure Cosmos DB * Couchbase Capella Database as a Service * Cloudant Data Layer<ref>Andrew Brust, "[https://web.archive.org/web/20120525065409/http://www.zdnet.com/blog/big-data/cloudant-makes-nosql-as-a-service-bigger/468 Cloudant Makes NoSQL as a Service Bigger]", ZDNet, Retrieved 2012-5-22.</ref> (CouchDB) * DataStax Astra DB powered by Apache Cassandra<ref>{{cite web |url=https://www.datastax.com/products/datastax-astra |title=DataStax Astra DB: DataStax managed services powered by Apache Cassandra |work=DataStax |access-date=2022-03-07}}</ref> * EnterpriseDB Postgres Plus Cloud Database<ref name=":0" /> * Google Cloud Bigtable<ref>{{cite web |url=https://cloud.google.com/bigtable/ |title=Bigtable: Scalable NoSQL Database Service |access-date=2016-11-28}}</ref> * Google Cloud Datastore<ref>{{cite web |url=https://cloud.google.com/datastore/ |title=Datastore: NoSQL Schemaless Database |access-date=2016-11-28}}</ref> * [https://www.mongodb.com/products/platform/atlas-database MongoDB Database as a Service (several options)]<ref>{{cite web |url=http://www.mongodb.com/cloud |title=MongoDB Atlas: Hosted MongoDB as a Service |access-date=2016-08-30}}</ref> * Oracle NoSQL Database Cloud Service<ref>{{cite web |url=https://cloud.oracle.com/en_US/nosql |title=NoSQL Database Cloud Service |work=Oracle Cloud |language=en |access-date=2017-11-29}}</ref> * ScyllaDB Cloud<ref name="computerweekly.com" /> * Amazon DocumentDB * YugabyteDB |}

== References == {{reflist|30em}}

Category:Cloud computing Category:Types of databases Category:Cloud databases