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Object–relational Mapping
Object–relational mapping (ORM, O/RM, and O/R mapping tool) in computer science is a programming technique for converting data between a relational database and the memory (usually the heap) of an object-oriented programming language. This creates, in effect, a virtual object database that can be used from within the programming language. In object-oriented programming, data-management tasks act on objects that combine scalar values into objects. For example, consider an address book entry that represents a single person along with zero or more phone numbers and zero or more addresses. This could be modeled in an object-oriented implementation by a "Person object" with an attribute/field to hold each data item that the entry comprises: the person's name, a list of phone numbers, and a list of addresses. The list of phone numbers would itself contain "PhoneNumber objects" and so on. Each such address-book entry is treated as a single object by the programming language ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Science
Computer science is the study of computation, information, and automation. Computer science spans Theoretical computer science, theoretical disciplines (such as algorithms, theory of computation, and information theory) to Applied science, applied disciplines (including the design and implementation of Computer architecture, hardware and Software engineering, software). Algorithms and data structures are central to computer science. The theory of computation concerns abstract models of computation and general classes of computational problem, problems that can be solved using them. The fields of cryptography and computer security involve studying the means for secure communication and preventing security vulnerabilities. Computer graphics (computer science), Computer graphics and computational geometry address the generation of images. Programming language theory considers different ways to describe computational processes, and database theory concerns the management of re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Persistence (computer Science)
In computer science, persistence refers to the characteristic of State (computer science), state of a system that outlives (persists for longer than) the Process (computing), process that created it. This is achieved in practice by storing the state as data in computer data storage. Programs have to transfer data to and from storage devices and have to provide mappings from the native Programming language, programming-language Data structure, data structures to the storage device data structures. Picture editing programs or Word processor, word processors, for example, achieve State (computer science), state persistence by saving their documents to computer file, files. Orthogonal or transparent persistence Persistence is said to be "Orthogonality#Computer science, orthogonal" or "transparent" when it is implemented as an intrinsic property of the execution environment of a program. An orthogonal persistence environment does not require any specific actions by programs running i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Object Database
An object database or object-oriented database is a database management system in which information is represented in the form of objects as used in object-oriented programming. Object databases are different from relational databases which are table-oriented. A third type, object–relational databases, is a hybrid of both approaches. Object databases have been considered since the early 1980s. Overview Object-oriented database management systems (OODBMSs) also called ODBMS (Object Database Management System) combine database capabilities with object-oriented programming language capabilities. OODBMSs allow object-oriented programmers to develop the product, store them as objects, and replicate or modify existing objects to make new objects within the OODBMS. Because the database is integrated with the programming language, the programmer can maintain consistency within one environment, in that both the OODBMS and the programming language will use the same model of representat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Common Object Request Broker Architecture
The Common Object Request Broker Architecture (CORBA) is a standard defined by the Object Management Group (OMG) designed to facilitate the communication of systems that are deployed on diverse platforms. CORBA enables collaboration between systems on different operating systems, programming languages, and computing hardware. CORBA uses an object-oriented model although the systems that use the CORBA do not have to be object-oriented. CORBA is an example of the distributed object paradigm. While briefly popular in the mid to late 1990s, CORBA's complexity, inconsistency, and high licensing costs have relegated it to being a niche technology. Overview CORBA enables communication between software written in different languages and running on different computers. Implementation details from specific operating systems, programming languages, and hardware platforms are all removed from the responsibility of developers who use CORBA. CORBA normalizes the method-call semantics betwee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AutoFetch
AutoFetch is a technique for automating the normally manual process of specifying prefetching hints for object–relational mapping queries. Ali Ibrahim and William Cook at the University of Texas at Austin developed the idea of "AutoFetch" including an implementation foHibernateand followed later by an implementation in Ebean. Benefits Improving the modularity of application code AutoFetch uses the program state (typically the call stack) to classify queries. This means that AutoFetch can tune the same query in different ways depending on HOW it was called. For example, a Data Access API such as findCustomer(int customerId) can be tuned differently depending on the callers of the method. Reducing the development and maintenance burden from Developers Because AutoFetch automatically gathers the profiling information developers do not need to manually try and gather this information and apply performance optimizations to the code. AutoFetch can monitor the object graph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comparison Of Object–relational Mapping Software
This table shows a comparison of notable and available ORM software products. See also * List of object–relational mapping software * Object–relational mapping References External links ormeter.net.NET LINQ LinQ (pronounced "link") is a Japanese girl group. Their name stands for "Love in Qshu", in reference to their hometown of Fukuoka, on the island of Kyushu. Members The members were formerly divided into two groups, Qty and Lady. Current *Yuumi ... ORM Comparison – Updated 30 July 2010 {{DEFAULTSORT:Comparison of object-relational mapping software Object–relational mapping Object-relational mapping ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Object–relational Mapping Software
This is a list of well-known object–relational mapping software. Java * Apache Cayenne, open-source for Java *Apache OpenJPA, open-source for Java * DataNucleus, open-source JDO and JPA implementation (formerly known as JPOX) * Ebean, open-source ORM framework *EclipseLink, Eclipse persistence platform *Enterprise JavaBeans (EJB) * Enterprise Objects Framework, Mac OS X/Java, part of Apple WebObjects *Hibernate, open-source ORM framework, widely used *Java Data Objects (JDO) * JOOQ Object Oriented Querying (jOOQ) *Kodo, commercial implementation of both Java Data Objects and Java Persistence API *TopLink by Oracle Node.jsBookshelf lightweight ORM tool for PostgreSQL, MySQL, and SQLite3Orange ORM Typescript/Javascript ORM for PostgreSQL, MySQL, SQL Server, SQLite, Oracle, SAP ASE and Cloudflare D1Prisma ORM Typescript/Javascript ORM for PostgreSQL, MySQL, SQL Server, SQLite, MongoDB, CockroachDB, Planetscale, MariaDBSequelize Node.js ORM tool for Postgres, MySQL, MariaDB, SQLite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Access Object
In software, a data access object (DAO) is a pattern that provides an abstract interface to some type of database or other persistence mechanism. By mapping application calls to the persistence layer, the DAO provides data operations without exposing database details. This isolation supports the single responsibility principle. It separates the data access the application needs, in terms of domain-specific objects and data types (the DAO's public interface), from how these needs can be satisfied with a specific DBMS (the implementation of the DAO). Although this design pattern is applicable to most programming languages, most software with persistence needs, and most databases, it is traditionally associated with Java EE applications and with relational databases (accessed via the JDBC API because of its origin in Sun Microsystems' best practice guidelines "Core J2EE Patterns". This object can be found in the Data Access layer of the 3-Tier Architecture. There are various ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Object–relational Impedance Mismatch
Object–relational impedance mismatch is a set of difficulties going between data in relational data stores and data in domain-driven object models. Relational Database Management Systems (RDBMS) is the standard method for storing data in a dedicated database, while object-oriented (OO) programming is the default method for business-centric design in programming languages. The problem lies in neither relational databases nor OO programming, but in the conceptual difficulty mapping between the two logic models. Both logical models are differently implementable using database servers, programming languages, design patterns, or other technologies. Issues range from application to enterprise scale, whenever stored relational data is used in domain-driven object models, and vice versa. Object-oriented data stores can trade this problem for other implementation difficulties. The term ''impedance mismatch'' comes from impedance matching in electrical engineering. Mismatches OO mathe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XQuery
XQuery (XML Query) is a query language and functional programming language designed to query and transform collections of structured and unstructured data, primarily in the form of XML. It also supports text data and, through implementation-specific extensions, other formats like binary and relational data. The language was developed by the XML Query working group of the W3C, with version 1.0 becoming a W3C Recommendation in January 2007. XQuery development is closely coordinated with the development of XSLT by the XSL Working Group. Both groups jointly maintain XPath, a shared component of XQuery and XSLT. XQuery extends XPath with features like FLWOR (For, Let, Where, Order by, Return) expressions, making it semantically similar to SQL but optimized for hierarchical rather than relational data. XQuery 3.1, published in March 2017, added support for JSON and introduced maps, arrays, and additional higher-order functions, significantly expanding the language's cap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Junction Table
An associative entity is a term used in relational and entity–relationship theory. A relational database requires the implementation of a base relation (or base table) to resolve many-to-many relationships. A base relation representing this kind of entity is called, informally, an associative table. As mentioned above, associative entities are implemented in a database structure using associative tables, which are tables that can contain references to columns from the same or different database tables within the same database. An associative (or junction) table maps two or more tables together by referencing the primary keys (PK) of each data table. In effect, it contains a number of foreign keys (FK), each in a many-to-one relationship from the junction table to the individual data tables. The PK of the associative table is typically composed of the FK columns themselves. Associative tables are colloquially known under many names, including association table, bridge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XML Database
An XML database is a data persistence software system that allows data to be specified, and stored, in XML format. This data can be queried, transformed, exported and returned to a calling system. XML databases are a flavor of document-oriented databases which are in turn a category of NoSQL database. Rationale for XML as a database format Reasons to store data in XML format as an XML database include: * An enterprise may have numerous XML documents with similar data, but dispersed in different XML formats. Conglomerating this data into a singular, standardized XML database structure will avoid compatibility issues * Data may need to be exposed or ingested as XML, so using another format such as relational forces double-modeling of the data * XML is very well suited to parse data, deeply nested data and mixed content (such as text with embedded markup tags) * XML is human readable whereas relational tables require expertise to access * Metadata is often available as XML * Sem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
