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Persistent Programming Language
Programming languages that natively and seamlessly allow objects to continue existing after the program has been closed down are called persistent programming languages. JADE is one such language. A persistent programming language is a programming language extended with constructs to handle persistent data. It is distinguished from embedded SQL in at least two ways: In a persistent programming language: * The query language is fully integrated with the host language and both share the same type system. * Any format changes required between the host language and the database are carried out transparently. In Embedded SQL: * Where the host language and data manipulation language have different type systems, code conversion operates outside of the OO type system, and hence has a higher chance of having undetected errors. * Format conversion must be handled explicitly and takes a substantial amount of code. Using Embedded SQL, a programmer is responsible for writing explicit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Programming Language
A programming language is a system of notation for writing computer programs. Most programming languages are text-based formal languages, but they may also be graphical. They are a kind of computer language. The description of a programming language is usually split into the two components of syntax (form) and semantics (meaning), which are usually defined by a formal language. Some languages are defined by a specification document (for example, the C programming language is specified by an ISO Standard) while other languages (such as Perl) have a dominant implementation that is treated as a reference. Some languages have both, with the basic language defined by a standard and extensions taken from the dominant implementation being common. Programming language theory is the subfield of computer science that studies the design, implementation, analysis, characterization, and classification of programming languages. Definitions There are many considerations when defini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Object (computer Science)
In computer science, an object can be a variable, a data structure, a function, or a method. As regions of memory, they contain value and are referenced by identifiers. In the object-oriented programming paradigm, ''object'' can be a combination of variables, functions, and data structures; in particular in class-based variations of the paradigm it refers to a particular instance of a class. In the relational model of database management, an object can be a table or column, or an association between data and a database entity (such as relating a person's age to a specific person). Object-based languages An important distinction in programming languages is the difference between an object-oriented language and an object-based language. A language is usually considered object-based if it includes the basic capabilities for an object: identity, properties, and attributes. A language is considered object-oriented if it is object-based and also has the capability of polymorphism, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Program
A computer program is a sequence or set of instructions in a programming language for a computer to execute. Computer programs are one component of software, which also includes documentation and other intangible components. A computer program in its human-readable form is called source code. Source code needs another computer program to execute because computers can only execute their native machine instructions. Therefore, source code may be translated to machine instructions using the language's compiler. ( Assembly language programs are translated using an assembler.) The resulting file is called an executable. Alternatively, source code may execute within the language's interpreter. If the executable is requested for execution, then the operating system loads it into memory and starts a process. The central processing unit will soon switch to this process so it can fetch, decode, and then execute each machine instruction. If the source code is requested for execution, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JADE Programming Language
JADE is a proprietary object-oriented software development and deployment platform product from the New Zealand-based Jade Software Corporation, first released in 1996. It consists of the JADE programming language, Integrated development environment and debugger, integrated application server and object database management system. Designed as an end-to-end development environment to allow systems to be coded in one language from the database server down to the clients, it also provides APIs for other languages, including .NET Framework, Java, C/ C++ and Web services. Although a free limited licence is available for development, using the JADE platform requires per-process fees to be paid. Language In syntax, JADE is very similar to Pascal; its syntax is based on the language Modula-2, which was derived from Pascal. While it includes innovations lacking in Pascal or Modula-2, it lacks certain features of other modern object-oriented languages such as C# and Java. JADE is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type System
In computer programming, a type system is a logical system comprising a set of rules that assigns a property called a type to every "term" (a word, phrase, or other set of symbols). Usually the terms are various constructs of a computer program, such as variables, expressions, functions, or modules. A type system dictates the operations that can be performed on a term. For variables, the type system determines the allowed values of that term. Type systems formalize and enforce the otherwise implicit categories the programmer uses for algebraic data types, data structures, or other components (e.g. "string", "array of float", "function returning boolean"). Type systems are often specified as part of programming languages and built into interpreters and compilers, although the type system of a language can be extended by optional tools that perform added checks using the language's original type syntax and grammar. The main purpose of a type system in a programming language ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Manipulation Language
A data manipulation language (DML) is a computer programming language used for adding (inserting), deleting, and modifying (updating) data in a database. A DML is often a sublanguage of a broader database language such as SQL, with the DML comprising some of the operators in the language. Read-only selecting of data is sometimes distinguished as being part of a separate data query language (DQL), but it is closely related and sometimes also considered a component of a DML; some operators may perform both selecting (reading) and writing. A popular data manipulation language is that of Structured Query Language (SQL), which is used to retrieve and manipulate data in a relational database. SQL92 Other forms of DML are those used by IMS/DLI, CODASYL databases, such as IDMS and others. SQL In SQL, the data manipulation language comprises the ''SQL-data change'' statements, which modify stored data but not the schema or database objects. Manipulation of persistent database object ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Format Conversion
Data conversion is the conversion of computer data from one format to another. Throughout a computer environment, data is encoded in a variety of ways. For example, computer hardware is built on the basis of certain standards, which requires that data contains, for example, parity bit checks. Similarly, the operating system is predicated on certain standards for data and file handling. Furthermore, each computer program handles data in a different manner. Whenever any one of these variables is changed, data must be converted in some way before it can be used by a different computer, operating system or program. Even different versions of these elements usually involve different data structures. For example, the changing of bits from one format to another, usually for the purpose of application interoperability or of the capability of using new features, is merely a data conversion. Data conversions may be as simple as the conversion of a text file from one character encoding syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MUMPS
MUMPS ("Massachusetts General Hospital Utility Multi-Programming System"), or M, is an imperative, high-level programming language with an integrated transaction processing key–value database. It was originally developed at Massachusetts General Hospital for managing hospital laboratory information systems. MUMPS technology has since expanded as the predominant database for health information systems and electronic health records in the United States. MUMPS-based information systems run over 40% of the hospitals in the U.S., run across all of the U.S. federal hospitals and clinics, and provide health information services for over 54% of patients across the U.S. A unique feature of the MUMPS technology is its integrated database language, allowing direct, high-speed read-write access to permanent disk storage. This provides tight integration of unlimited applications within a single database, and provides extremely high performance and reliability as an online transaction pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caché ObjectScript
Caché ObjectScript is a part of the Caché database system sold by InterSystems. The language is a functional superset of the ANSI-standard MUMPS programming language. Since Caché is at its core a MUMPS implementation, it can run ANSI MUMPS routines with no change. To appeal as a commercial product, Caché implements support for object-oriented programming, a macro preprocessing language, embedded SQL for ANSI-standard SQL access to M's built-in database, procedure and control blocks using C-like brace syntax, procedure-scoped variables, and relaxed whitespace syntax limitations. The language has private and public variables and globals. Global has a different meaning in this language than in most; such variables are global across routines, processes, and sessions. Thus, editing a global variable is making permanent and immediate changes to a system-universal database (which survives reboots, etc.). The scope of a private variable is the local function, the scope of a pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Object-oriented Database Management System
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] |
Object Prevalence
System prevalence is a simple software architectural pattern that combines system images (snapshots) and transaction journaling to provide speed, performance scalability, transparent persistence and transparent live mirroring of computer system state. In a prevalent system, state is kept in memory in native format, all transactions are journaled and System images are regularly saved to disk. System images and transaction journals can be stored in language-specific serialization format for speed or in XML format for cross-language portability. The first usage of the term and generic, publicly available implementation of a system prevalence layer was Prevayler, written for Java by Klaus Wuestefeld in 2001. Advantages Simply keeping system state in RAM in its normal, natural, language-specific format is orders of magnitude faster and more programmer-friendly than the multiple conversions that are needed when it is stored and retrieved from a DBMS. As an example, Martin Fow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
