A data store is a data repository of a set of integrated objects. These objects are modeled using classes defined in database schema

Database schema

A database schema of a database system is its structure described in a formal language supported by the database management system and refers to the organization of data to create a blueprint of how a database will be constructed...

s. Data store includes not only data repositories like databases, it is a more general concept that includes also flat files that can store data.

Some data stores do represent data in only one schema, while other data stores use several schemas for this task. An example are RDBMS-based data stores like MySQL

MySQL

MySQL officially, but also commonly "My Sequel") is a relational database management system that runs as a server providing multi-user access to a number of databases. It is named after developer Michael Widenius' daughter, My...

 or ORACLE

Oracle Database

The Oracle Database is an object-relational database management system produced and marketed by Oracle Corporation....

.

Types

Datastores can be of different types.

• The widely used data store type are relational database
  Relational database
  A relational database is a database that conforms to relational model theory. The software used in a relational database is called a relational database management system . Colloquial use of the term "relational database" may refer to the RDBMS software, or the relational database itself...
  
  s. (Examples: Microsoft SQL Server
  Microsoft SQL Server
  Microsoft SQL Server is a relational database server, developed by Microsoft: It is a software product whose primary function is to store and retrieve data as requested by other software applications, be it those on the same computer or those running on another computer across a network...
  
  , MySQL, ORACLE, Postgresql
  PostgreSQL
  PostgreSQL, often simply Postgres, is an object-relational database management system available for many platforms including Linux, FreeBSD, Solaris, MS Windows and Mac OS X. It is released under the PostgreSQL License, which is an MIT-style license, and is thus free and open source software...
  
  )
• Object-oriented databases, like Caché
  Caché (software)
  InterSystems Caché is a commercial object database management system from InterSystems Corporation. It provides object and SQL access to the database, as well as allowing direct manipulation of Caché’s underlying data structures. The company claims Caché is the world’s fastest object database...
  
   or ConceptBase
  ConceptBase
  ConceptBase is a deductive and object-oriented database management system developed at University of Aachen and Tilburg University. It is mainly used for conceptual modeling and metamodeling in the domain of software engineering and related domains....
  
  . They can save object
  Object (computer science)
  In computer science, an object is any entity that can be manipulated by the commands of a programming language, such as a value, variable, function, or data structure...
  
  s of an object-oriented
  Object-oriented programming
  Object-oriented programming is a programming paradigm using "objects" – data structures consisting of data fields and methods together with their interactions – to design applications and computer programs. Programming techniques may include features such as data abstraction,...
  
   design.
• Operational data store
  Operational data store
  An operational data store is a database designed to integrate data from multiple sources for additional operations on the data. The data is then passed back to operational systems for further operations and to the data warehouse for reporting....
  
  s
• Schemaless data stores, like Distributed data store
  Distributed data store
  A distributed data store is a blurred concept and means either a distributed database where users store their information on a number of nodes, or a network in which a user stores their information on a number of peer network nodes ....
  
  s (e.g. Apache Cassandra or Dynamo
  Dynamo (storage system)
  Dynamo is a highly available, proprietary key-value structured storage system or a distributed data store. It has properties of both databases and distributed hash tables...
  
  ).