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81-420: Dataphor has been praised for its adherence to relational principles, more closely so than any SQL product. The stated purpose of Dataphor is to attempt to raise the bar of automation when building and maintaining complex software applications. Originally referred to as a framework, Dataphor provides more of a software development platform, complete with its own programming and user interface paradigms. Dataphor

162-627: A distributed operating system . IP Pascal is an implementation of the Pascal programming language using Micropolis DOS, but was moved rapidly to CP/M-80 running on the Z80. It was moved to the 80386 machine types in 1994, and exists today as Windows XP and Linux implementations. In 2008, the system was brought up to a new level and the resulting language termed "Pascaline" (after Pascal's calculator ). It includes objects, namespace controls, dynamic arrays , and many other extensions, and generally features

243-631: A standard of the American National Standards Institute (ANSI) in 1986 and of the International Organization for Standardization (ISO) in 1987. Since then, the standard has been revised multiple times to include a larger set of features and incorporate common extensions. Despite the existence of standards, virtually no implementations in existence adhere to it fully, and most SQL code requires at least some changes before being ported to different database systems. SQL

324-488: A "byte machine", again, because it would be a better fit for byte oriented microprocessors. UCSD Pascal formed the basis of many systems, including Apple Pascal. Borland Pascal was not based on the UCSD codebase, but arrived during the popular period of UCSD and matched many of its features. This started the line that ended with Delphi Pascal and the compatible Open Source compiler FPC/Lazarus. The ISO standard for Pascal, ISO 7185,

405-649: A 1.0 release in 2001. In early 2008, the Alphora name and the Dataphor product were acquired by Database Consulting Group , which was founded by the original architects of Dataphor, who left Softwise in 2007. After the acquisition, Dataphor was re-licensed as open source under the BSD License . Dataphor utilizes the Microsoft .NET Framework and is written entirely in C#. The following is

486-474: A local RDB and receive tables of data and status indicators in reply from remote RDBs. SQL statements can also be compiled and stored in remote RDBs as packages and then invoked by package name. This is important for the efficient operation of application programs that issue complex, high-frequency queries. It is especially important when the tables to be accessed are located in remote systems. The messages, protocols, and structural components of DRDA are defined by

567-543: A much more complex language, ALGOL 68 . The complexity of this language led to considerable difficulty producing high-performance compilers, and it was not widely used in the industry. This left an opening for newer languages. Pascal was influenced by the ALGOL W efforts, with the explicit goals of teaching programming in a structured fashion and for the development of system software. A generation of students used Pascal as an introductory language in undergraduate courses. One of

648-628: A return statement and expressions as names of types. TMT Pascal was the first Borland -compatible compiler for 32-bit MS-DOS compatible protected mode , OS/2 , and Win32 . It extends the language with function and operator overloading . The universities of Wisconsin–Madison , Zürich , Karlsruhe , and Wuppertal developed the Pascal-SC and Pascal-XSC ( Extensions for Scientific Computation ) compilers, aimed at programming numerical computations. Development for Pascal-SC started in 1978 supporting ISO 7185 Pascal level 0, but level 2 support

729-470: A roadblock to full use of SQL's user-defined types. JSON support, for example, needed to be added by a new standard in 2016. The concept of Null is the subject of some debate . The Null marker indicates the absence of a value, and is distinct from a value of 0 for an integer column or an empty string for a text column. The concept of Nulls enforces the 3-valued-logic in SQL , which is a concrete implementation of

810-420: A single statement or a begin - end statements block. Pascal also has data structuring constructs not included in the original ALGOL 60 types , like records , variants, pointers , enumerations , and sets and procedure pointers. Such constructs were in part inherited or inspired from Simula 67, ALGOL 68 , Niklaus Wirth 's own ALGOL W and suggestions by C. A. R. Hoare . Pascal programs start with

891-423: A storage engine of its own, it can also connect to other RDBMSes, and use them as a storage engine. Dataphor can use the following DBMSes as storage engines: Dataphor can access Oracle, IBM Db2, Microsoft SQL Server, PostgreSQL, MySQL and any other storage engine with a single unified language. The Dataphor Frontend library provides for the delivery of dynamically derived, or pre-designed static forms. The library

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972-494: A subset of the Pascal language. Pascal-P5, created outside the Zürich group, accepts the full Pascal language and includes ISO 7185 compatibility. Pascal-P6 is a follow on to Pascal-P5 that along with other features, aims to be a compiler for specific CPUs, including AMD64. UCSD Pascal branched off Pascal-P2, where Kenneth Bowles used it to create the interpretive UCSD p-System. It was one of three operating systems available at

1053-429: A summary of the various technology components of Dataphor: The Dataphor Server has several components including: While Dataphor supports a SQL flavor they call "RealSQL", D4 is the preferred language for use within Dataphor, D4 supports DDL and DML statements. D4 queries tend to look like relational algebra expressions with written out names of operators. For example: D4 has a Pascal -like syntax. D4 sample code

1134-473: A very simple "Hello, World!" program : A Type Declaration in Pascal is used to define a range of values which a variable of that type is capable of storing. It also defines a set of operations that are permissible to be performed on variables of that type. The predefined types are: The range of values allowed for the basic types (except Boolean) is implementation defined. Functions are provided for some data conversions. For conversion of real to integer ,

1215-440: Is an integrated development environment for: The Dataphor Windows Client is a thin client in the sense that it is not pre-programmed for a particular application. The Windows client establishes a connection to a Dataphor Server, from which it (through D4) requests form definitions and coordinates the manipulation of application data. The DFD documents are interpreted into concrete Windows Forms controls, but while maintaining

1296-676: Is broadly divided into two components: the Dataphor Server, and the Dataphor Frontend. The purpose of the Dataphor Server is to provide a standardized language and runtime for the definition, manipulation, and integrity of application data. The Frontend is concerned with the dynamic derivation of user interfaces and the presentation thereof in either the Windows or Web thin client. Dataphor does not employ SQL as its primary database language since SQL purportedly violates important principles of

1377-440: Is essentially a declarative language ( 4GL ), it also includes procedural elements. SQL was one of the first commercial languages to use Edgar F. Codd 's relational model . The model was described in his influential 1970 paper, "A Relational Model of Data for Large Shared Data Banks". Despite not entirely adhering to the relational model as described by Codd , SQL became the most widely used database language. SQL became

1458-462: Is exposed as a standard set of D4 functions (called operators in D4) such as Form (' library ', ' name ') and Derive (' D4 expression ', ' form type '). The resulting forms are described in an XML dialect called a Dataphor Form Document (DFD). The form description is high-level, consisting of a general description of the user interface aspects as they apply independent of client platform. Dataphoria

1539-541: Is still used for developing Windows applications, and can cross-compile code to other systems. Free Pascal is an open source, cross-platform alternative with its own graphical IDE called Lazarus . The first Pascal compiler was designed in Zürich for the CDC 6000 series mainframe computer family. Niklaus Wirth reports that a first attempt to implement it in FORTRAN 66 in 1969

1620-563: Is superior to the procedural style operations used in SQL . The DML syntax at first glance may appear to be similar to SQLs syntax, but because of D4's closer ties to relational algebra , the syntax has a cleaner definition, and most users greatly prefer it over SQL. The Imperative Language in D4 is remarkably similar to Pascal in many respects. The largest distinction being that D4 also allows DDL and DML statements to be run in regular procedural code. D4

1701-652: Is usually capable of recompiling itself when new features are added to the language, or when the compiler is to be ported to a new environment. The GNU Pascal compiler is one notable exception, being written in C. The first successful port of the CDC Pascal compiler to another mainframe was completed by Welsh and Quinn at the Queen's University of Belfast (QUB) in 1972. The target was the International Computers Limited (ICL) 1900 series . This compiler, in turn,

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1782-557: Is usually written in UpperCamelCase , which is also widely used in Pascal and Delphi systems. Like most query languages, D4 has a Data Definition Language (DDL) and a Data Manipulation Language (DML). D4 also has an Imperative Language for procedural code. The DDL for Dataphor bears many similarities to other DBMSs, but with an obviously Pascal-like twist. Many of the allowed DDL operations, like constraints, allow relational declarative statements to be used, which many believe

1863-457: The program keyword with a list of external file descriptors as parameters (not required in Turbo Pascal etc.); then follows the main block bracketed by the begin and end keywords. Semicolons separate statements , and the full stop (i.e., a period) ends the whole program (or unit ). Letter case is ignored in Pascal source. Here is an example of the source code in use for

1944-485: The C-family ), Pascal allows nested procedure definitions to any level of depth, and also allows most kinds of definitions and declarations inside subroutines (procedures and functions). A program is thus syntactically similar to a single procedure or function. This is similar to the block structure of ALGOL 60, but restricted from arbitrary block statements to just procedures and functions. Pascal became very successful in

2025-485: The Distributed Data Management Architecture . Distributed SQL processing ala DRDA is distinctive from contemporary distributed SQL databases. SQL deviates in several ways from its theoretical foundation, the relational model and its tuple calculus. In that model, a table is a set of tuples, while in SQL, tables and query results are lists of rows; the same row may occur multiple times, and

2106-451: The Euler programming language . Euler was based on ALGOL's syntax and many concepts but was not a derivative. Its primary goal was to add dynamic lists and types, allowing it to be used in roles similar to Lisp . The language was published in 1965. By this time, a number of problems in ALGOL had been identified, notably the lack of a standardized string system. The group tasked with maintaining

2187-605: The database , while prior versions of SQL Server were restricted to unmanaged extended stored procedures primarily written in C. PostgreSQL lets users write functions in a wide variety of languages—including Perl , Python , Tcl , JavaScript (PL/V8) and C. SQL implementations are incompatible between vendors and do not necessarily completely follow standards. In particular, date and time syntax, string concatenation, NULL s, and comparison case sensitivity vary from vendor to vendor. PostgreSQL and Mimer SQL strive for standards compliance, though PostgreSQL does not adhere to

2268-517: The relational model . Dataphor's D4 language is based on the principles of Christopher J Date 's and Hugh Darwen 's Tutorial D, but with a Pascal -like imperative syntax. Though Dataphor espouses to be truly relational, it does incorporate the concept of NULLs as found in SQL, which many claim to be contraindicated by the Relational Model. NULLs and the matter of managing missing information, however, continue to be debated. In addition to

2349-793: The 1970s, SQL offered two main advantages over older read–write APIs such as ISAM or VSAM . Firstly, it introduced the concept of accessing many records with one single command . Secondly, it eliminates the need to specify how to reach a record, i.e., with or without an index . Originally based upon relational algebra and tuple relational calculus , SQL consists of many types of statements, which may be informally classed as sublanguages , commonly: Data query Language (DQL), Data Definition Language (DDL), Data Control Language (DCL), and Data Manipulation Language (DML). The scope of SQL includes data query, data manipulation (insert, update, and delete), data definition ( schema creation and modification), and data access control. Although SQL

2430-404: The 1970s, notably on the burgeoning minicomputer market. Compilers were also available for many microcomputers as the field emerged in the late 1970s. It was widely used as a teaching language in university -level programming courses in the 1980s, and also used in production settings for writing commercial software during the same period. It was displaced by the C programming language during

2511-485: The 1970s. Chamberlin and Boyce's first attempt at a relational database language was SQUARE (Specifying Queries in A Relational Environment), but it was difficult to use due to subscript/superscript notation. After moving to the San Jose Research Laboratory in 1973, they began work on a sequel to SQUARE. The original name SEQUEL, which is widely regarded as a pun on QUEL , the query language of Ingres ,

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2592-536: The C-based application programming interface (API) of Microsoft Windows directly. These extensions included null-terminated strings , pointer arithmetic , function pointers , an address-of operator, and unsafe typecasts . Turbo Pascal and other derivatives with unit or module structures are modular programming languages. However, it does not provide a nested module concept or qualified import and export of specific symbols. Super Pascal adds non-numeric labels,

2673-535: The ISO in 1987. It is maintained by ISO/IEC JTC 1, Information technology, Subcommittee SC 32, Data management and interchange . Until 1996, the National Institute of Standards and Technology (NIST) data-management standards program certified SQL DBMS compliance with the SQL standard. Vendors now self-certify the compliance of their products. The original standard declared that the official pronunciation for "SQL"

2754-614: The Lisa Pascal and Mac Pascal compilers. In the 1980s, Anders Hejlsberg wrote the Blue Label Pascal compiler for the Nascom -2. A reimplementation of this compiler for the IBM PC was marketed under the names Compas Pascal and PolyPascal before it was acquired by Borland and renamed Turbo Pascal . Turbo Pascal became hugely popular, thanks to an aggressive pricing strategy, having one of

2835-623: The Macintosh, a further version was created and named Object Pascal . This was introduced on the Mac in 1985 as part of the MacApp application framework , and became Apple's main development language into the early 1990s. The Object Pascal extensions were added to Turbo Pascal with the release of version 5.5 in 1989. Over the years, Object Pascal became the basis of the Delphi system for Microsoft Windows , which

2916-602: The Pascal source code . The typesetting system TeX by Donald Knuth was written in WEB , the original literate programming system, based on DEC PDP-10 Pascal. Successful commercial applications like Adobe Photoshop were written in Macintosh Programmer's Workshop Pascal, while applications like Total Commander , Skype and Macromedia Captivate were written in Delphi ( Object Pascal ). Apollo Computer used Pascal as

2997-566: The Pascal concepts led to the languages Modula-2 and Oberon , both developed by Wirth. Much of the history of computer language design during the 1960s can be traced to the ALGOL 60 language. ALGOL was developed during the 1950s with the explicit goal of being able to clearly describe algorithms . It included a number of features for structured programming that remain common in languages to this day. Shortly after its introduction, in 1962 Wirth began working on his dissertation with Helmut Weber on

3078-895: The Pascal-P4 compiler, which created native binary object files , was released for the IBM System/370 mainframe computer by the Australian Atomic Energy Commission ; it was named the AAEC Pascal 8000 Compiler after the abbreviation of the name of the commission. Apple Computer created its own Lisa Pascal for the Lisa Workshop in 1982, and ported the compiler to the Apple Macintosh and MPW in 1985. In 1985 Larry Tesler , in consultation with Niklaus Wirth, defined Object Pascal and these extensions were incorporated in both

3159-522: The Web "Client" is a client relative to the Dataphor Server, but a server relative to the end web browser. SQL Structured Query Language ( SQL ) ( pronounced S-Q-L ; or alternatively as "sequel") is a domain-specific language used to manage data, especially in a relational database management system (RDBMS). It is particularly useful in handling structured data , i.e., data incorporating relations among entities and variables. Introduced in

3240-572: The conceptual DOM of the DFD. The Dataphor Web Client is a basic implementation of a Dataphor client, which is manifest as an ASP.NET web application. Like the Windows Client, the Web Client connects to and requests forms and data from and instance of the Dataphor Server. Rather than synchronizing a DFD to Windows controls, however, the Web Client renders HTML which is displayed in a browser. In this way,

3321-590: The data management focus of the Dataphor Server, Dataphor includes tools which allow the presentation of user interfaces through Windows and Web "thin" clients. Dataphor takes advantage of the relational inference capabilities of the Dataphor compiler in order to allow complete GUI forms to be derived directly from the data model. The unique aspect of Dataphor's user interface "derivation" is that it may be based on any relational expression (query) rather than merely base tables. Dataphor strives for theoretical compliance to relational principles. While they try to adhere to

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3402-514: The early history on Pascal can be found in the Pascal User's Group newsletters at: Pascal Users Group Newsletters . During work on the Lisa, Larry Tesler began corresponding with Wirth on the idea of adding object-oriented extensions to the language, to make Pascal a Multi-paradigm programming language . This led initially to Clascal , introduced in 1983. As the Lisa program faded and was replaced by

3483-656: The early successes for the language was the introduction of UCSD Pascal , a version that ran on a custom operating system that could be ported to different platforms. A key platform was the Apple II , where it saw widespread use as Apple Pascal . This led to Pascal becoming the primary high-level language used for development in the Apple Lisa , and later, the Macintosh . Parts of the original Macintosh operating system were hand-translated into Motorola 68000 assembly language from

3564-515: The first 16-bit implementation. A completely new compiler was completed by Welsh et al. at QUB in 1977. It offered a source-language diagnostic feature (incorporating profiling, tracing and type-aware formatted postmortem dumps) that was implemented by Findlay and Watt at Glasgow University. This implementation was ported in 1980 to the ICL 2900 series by a team based at Southampton University and Glasgow University. The Standard Pascal Model Implementation

3645-492: The first full-screen IDEs, and very fast turnaround time (just seconds to compile, link, and run). It was written and highly optimized entirely in assembly language , making it smaller and faster than much of the competition. In 1986, Anders ported Turbo Pascal to the Macintosh and incorporated Apple's Object Pascal extensions into Turbo Pascal. These extensions were then added back into the PC version of Turbo Pascal for version 5.5. At

3726-420: The following functions are available: round (which rounds to integer using banker's rounding ) and trunc (rounds towards zero). The programmer has the freedom to define other commonly used data types (e.g. byte, string, etc.) in terms of the predefined types using Pascal's type declaration facility, for example Often-used types like byte and string are already defined in many implementations. Normally

3807-404: The general 3-valued logic . Another popular criticism is that it allows duplicate rows, making integration with languages such as Python , whose data types might make accurately representing the data difficult, in terms of parsing and by the absence of modularity. This is usually avoided by declaring a primary key, or a unique constraint, with one or more columns that uniquely identify a row in

3888-412: The implementation. Pascal (programming language) Pascal is an imperative and procedural programming language , designed by Niklaus Wirth as a small, efficient language intended to encourage good programming practices using structured programming and data structuring . It is named after French mathematician, philosopher and physicist Blaise Pascal . Pascal was developed on

3969-407: The language had begun the ALGOL X process to identify improvements, calling for submissions. Wirth and Tony Hoare submitted a conservative set of modifications to add strings and clean up some of the syntax. These were considered too minor to be worth using as the new standard ALGOL, so Wirth wrote a compiler for the language, which became named ALGOL W . The ALGOL X efforts would go on to choose

4050-471: The language rapidly, a compiler porting kit was created in Zürich that included a compiler that generated so called p-code for a virtual stack machine, i.e., code that lends itself to reasonably efficient interpretation, along with an interpreter for that code – the Pascal-P system. The P-system compilers were named Pascal-P1, Pascal-P2, Pascal-P3, and Pascal-P4. Pascal-P1 was the first version, and Pascal-P4

4131-522: The late 1970s, Relational Software, Inc. (now Oracle Corporation ) saw the potential of the concepts described by Codd, Chamberlin, and Boyce, and developed their own SQL-based RDBMS with aspirations of selling it to the U.S. Navy , Central Intelligence Agency , and other U.S. government agencies. In June 1979, Relational Software introduced one of the first commercially available implementations of SQL, Oracle V2 (Version2) for VAX computers. By 1986, ANSI and ISO standard groups officially adopted

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4212-463: The late 1980s and early 1990s as UNIX -based systems became popular, and especially with the release of C++ . A derivative named Object Pascal designed for object-oriented programming was developed in 1985. This was used by Apple Computer (for the Lisa and Macintosh machines) and Borland in the late 1980s and later developed into Delphi on the Microsoft Windows platform. Extensions to

4293-485: The launch of the original IBM Personal Computer . UCSD Pascal used an intermediate code based on byte values, and thus was one of the earliest bytecode compilers . Apple Pascal was released in 1979 for the Apple II and Apple III computer systems. It was an implementation of, or largely based on, UCSD Pascal. Pascal-P1 through Pascal-P4 were not, but rather based on the CDC 6600 60-bit word length. A compiler based on

4374-594: The logical layer change. E.g. when a new column is added to the system, no additional development is needed to have that be a new field visible to the users for viewing or editing. Hugh Darwen has referred to D4, as a notable project in his talk entitled The Askew Wall . Chris Date refers to Dataphor as a product that attempts to implement the Third Manifesto. Fabian Pascal calls Dataphor "Truly Relational", and "superior to SQL" In 1999, point of sale systems developer Softwise Inc , found they were writing much of

4455-466: The most popular commercial and proprietary SQL DBMSs, are Oracle (whose DATE behaves as DATETIME , and lacks a TIME type) and MS SQL Server (before the 2008 version). As a result, SQL code can rarely be ported between database systems without modifications. Several reasons for the lack of portability between database systems include: SQL was adopted as a standard by the ANSI in 1986 as SQL-86 and

4536-556: The order of rows can be employed in queries (e.g., in the LIMIT clause). Critics argue that SQL should be replaced with a language that returns strictly to the original foundation: for example, see The Third Manifesto by Hugh Darwen and C.J. Date (2006, ISBN   0-321-39942-0 ). Early specifications did not support major features, such as primary keys. Result sets could not be named, and subqueries had not been defined. These were added in 1992. The lack of sum types has been described as

4617-711: The pattern of the ALGOL 60 language. Wirth was involved in the process to improve the language as part of the ALGOL X efforts and proposed a version named ALGOL W . This was not accepted, and the ALGOL X process bogged down. In 1968, Wirth decided to abandon the ALGOL X process and further improve ALGOL W, releasing this as Pascal in 1970. On top of ALGOL's scalars and arrays , Pascal enables defining complex datatypes and building dynamic and recursive data structures such as lists , trees and graphs . Pascal has strong typing on all objects, which means that one type of data cannot be converted to or interpreted as another without explicit conversions. Unlike C (and most languages in

4698-427: The pattern: ISO/IEC 9075-n:yyyy Part n: title , or, as a shortcut, ISO/IEC 9075 . Interested parties may purchase the standards documents from ISO, IEC, or ANSI. Some old drafts are freely available. ISO/IEC 9075 is complemented by ISO/IEC 13249: SQL Multimedia and Application Packages and some Technical reports . A distinction should be made between alternatives to SQL as a language, and alternatives to

4779-475: The principles in The Third Manifesto, they deviated in a few places from what the Third Manifesto strived for, but not in places that were violations of Codd's 12 rules . E.g. they included nulls, but they claim to have a systematic treatment of them. While many systems built on SQL fail miserably with respect to Codd's rule 9 "Logical data independence", Dataphor applications can automatically change when

4860-489: The relational model itself. Below are proposed relational alternatives to the SQL language. See navigational database and NoSQL for alternatives to the relational model. Distributed Relational Database Architecture (DRDA) was designed by a workgroup within IBM from 1988 to 1994. DRDA enables network-connected relational databases to cooperate to fulfill SQL requests. An interactive user or program can issue SQL statements to

4941-439: The same code over and over again, and looked for a tool to automate their database applications. They didn't find an application which did what they want, so they created a division of their company, called it Alphora, and set some of their developers to build such a tool. That tool became Dataphor. It is said to be the first truly relational DBMS since IBM Business System 12 . Development of Dataphor began shortly before 2000, with

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5022-423: The same functionality and type protection as C# . It is the only such implementation that is also compatible with the original Pascal implementation, which is standardized as ISO 7185. Pascal, in its original form, is a purely procedural language and includes the traditional array of ALGOL -like control structures with reserved words such as if , then , else , while , for , and case , ranging on

5103-543: The same time Microsoft also implemented the Object Pascal compiler. Turbo Pascal 5.5 had a large influence on the Pascal community, which began concentrating mainly on the IBM PC in the late 1980s. Many PC hobbyists in search of a structured replacement for BASIC used this product. It also began to be adopted by professional developers. Around the same time a number of concepts were imported from C to let Pascal programmers use

5184-618: The standard "Database Language SQL" language definition. New versions of the standard were published in 1989, 1992, 1996, 1999, 2003, 2006, 2008, 2011, 2016 and most recently, 2023. The SQL language is subdivided into several language elements, including: SQL is designed for a specific purpose: to query data contained in a relational database . SQL is a set -based, declarative programming language , not an imperative programming language like C or BASIC . However, extensions to Standard SQL add procedural programming language functionality, such as control-of-flow constructs. In addition to

5265-572: The standard SQL/PSM extensions and proprietary SQL extensions, procedural and object-oriented programmability is available on many SQL platforms via DBMS integration with other languages. The SQL standard defines SQL/JRT extensions (SQL Routines and Types for the Java Programming Language) to support Java code in SQL databases. Microsoft SQL Server 2005 uses the SQLCLR (SQL Server Common Language Runtime) to host managed .NET assemblies in

5346-571: The standard in all cases. For example, the folding of unquoted names to lower case in PostgreSQL is incompatible with the SQL standard, which says that unquoted names should be folded to upper case. Thus, according to the standard, Foo should be equivalent to FOO , not foo . Popular implementations of SQL commonly omit support for basic features of Standard SQL, such as the DATE or TIME data types. The most obvious such examples, and incidentally

5427-399: The system will use a word to store the data. For instance, the byte type may be stored in a machine integer - 32 bits perhaps - rather than an 8-bit value. Pascal does not contain language elements that allow the basic storage types to be defined more granularly. This capability was included in a number of Pascal extensions and follow-on languages, while others, like Modula-2 , expanded

5508-495: The systems programming language for its operating systems beginning in 1980. Variants of Pascal have also been used for everything from research projects to PC games and embedded systems . Newer Pascal compilers exist which are widely used. Wirth's example compiler meant to propagate the language, the Pascal-P system, used a subset of the language designed to be the minimal subset of the language that could compile itself. The idea

5589-607: The table. In a sense similar to object–relational impedance mismatch , a mismatch occurs between the declarative SQL language and the procedural languages in which SQL is typically embedded. The SQL standard defines three kinds of data types (chapter 4.1.1 of SQL/Foundation): Constructed types are one of ARRAY, MULTISET, REF(erence), or ROW. User-defined types are comparable to classes in object-oriented language with their own constructors, observers, mutators, methods, inheritance, overloading, overwriting, interfaces, and so on. Predefined data types are intrinsically supported by

5670-575: Was added at a later stage. Pascal-SC originally targeted the Z80 processor, but was later rewritten for DOS ( x86 ) and 68000 . Pascal-XSC has at various times been ported to Unix (Linux, SunOS , HP-UX , AIX ) and Microsoft/IBM (DOS with EMX , OS/2, Windows ) operating systems. It operates by generating intermediate C source code which is then compiled to a native executable. Some of the Pascal-SC language extensions have been adopted by GNU Pascal . Pascal Sol

5751-627: Was also based on this compiler, having been adapted, by Welsh and Hay at Manchester University in 1984, to check rigorously for conformity to the BSI 6192/ISO 7185 Standard and to generate code for a portable abstract machine. The first Pascal compiler written in North America was constructed at the University of Illinois under Donald B. Gillies for the PDP-11 and generated native machine code. To propagate

5832-417: Was an initialism : / ˌ ɛ s ˌ k juː ˈ ɛ l / ("ess cue el"). Regardless, many English-speaking database professionals (including Donald Chamberlin himself ) use the acronym -like pronunciation of / ˈ s iː k w əl / ("sequel"), mirroring the language's prerelease development name, "SEQUEL". The SQL standard has gone through a number of revisions: The standard is commonly denoted by

5913-502: Was designed around 1983 by a French team to implement a Unix-like system named Sol. It was standard Pascal level-1 (with parameterized array bounds) but the definition allowed alternative keywords and predefined identifiers in French and the language included a few extensions to ease system programming (e.g. an equivalent to lseek). The Sol team later on moved to the ChorusOS project to design

5994-440: Was initially developed at IBM by Donald D. Chamberlin and Raymond F. Boyce after learning about the relational model from Edgar F. Codd in the early 1970s. This version, initially called SEQUEL (Structured English Query Language), was designed to manipulate and retrieve data stored in IBM's original quasirelational database management system, System R , which a group at IBM San Jose Research Laboratory had developed during

6075-627: Was later changed to SQL (dropping the vowels) because "SEQUEL" was a trademark of the UK-based Hawker Siddeley Dynamics Engineering Limited company. The label SQL later became the acronym for Structured Query Language. After testing SQL at customer test sites to determine the usefulness and practicality of the system, IBM began developing commercial products based on their System R prototype, including System/38 , SQL/DS , and IBM Db2 , which were commercially available in 1979, 1981, and 1983, respectively. In

6156-475: Was named after the similar-sounding Dataphor, the system that uses the language. It was some time after these names were decided that its creators discovered Tutorial D, and the coincidence it had with that name. Since discovering Tutorial D and The Third Manifesto, the creators have used The Third Manifesto as a guide in making Dataphor and D4. Since then, Hugh Darwen has referred to D4, as a notable project in his talk entitled The Askew Wall . While Dataphor has

6237-466: Was published in 1983 and was widely implemented and used on mainframes, minicomputers and IBM-PCs and compatibles from 16 bits to 32 bits. The two dialects of Pascal most in use towards the end of the 20th century and up until today are the ISO 7185 standard version and the Delphi/Turbo Pascal versions (of which the two Borland versions are mostly compatible with each other). The source for much of

6318-470: Was that this could allow bootstrapping the compiler, which would then be extended to full Pascal language status. This was done with several compilers, but one notable exception was UCSD Pascal, which was based on Pascal-P2. It kept the subset status of the language based on the idea that this would run better on the new (then) microprocessors with limited memory. UCSD also converted the Pascal-P2 interpreter into

6399-544: Was the last to come from Zürich. The version termed Pascal-P1 was coined after the fact for the many different sources for Pascal-P that existed. The compiler was redesigned to enhance portability , and issued as Pascal-P2. This code was later enhanced to become Pascal-P3, with an intermediate code backward compatible with Pascal-P2, and Pascal-P4, which was not backward compatible. The Pascal-P4 compiler–interpreter can still be run and compiled on systems compatible with original Pascal (as can Pascal-P2). However, it only accepts

6480-587: Was the parent of the Pascal compiler for the Information Computer Systems (ICS) Multum minicomputer. The Multum port was developed – with a view to using Pascal as a systems programming language – by Findlay, Cupples, Cavouras and Davis, working at the Department of Computing Science in Glasgow University . It is thought that Multum Pascal, which was completed in the summer of 1973, may have been

6561-408: Was unsuccessful due to FORTRAN 66's inadequacy to express complex data structures. The second attempt was implemented in a C-like language (Scallop by Max Engeli) and then translated by hand (by R. Schild) to Pascal itself for boot-strapping. It was operational by mid-1970. Many Pascal compilers since have been similarly self-hosting , that is, the compiler is itself written in Pascal, and the compiler

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