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Kexi/Håndbog/Introduktion til databaser/Programmer til at lave databaser

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Revision as of 17:36, 13 August 2012 by Claus chr (talk | contribs) (Importing a new version from external source)

Programmer til at lave databaser

Indtil nu har du lært om de generelle egenskaber ved databaser uden at komme ind på detaljer om specifikke programmer til at designe dem.

De første databaser var bygget sammen med store mainframecomputere i 60'erne, f.eks. IBM System/360. Det var før PC'ens tid, så databaserne krævede højt specialiseret personel. Selvom de gamle computeres hardware var upålidelig, meget langsommere og havde mindre lagerkapacitet, så er et træk ved deres databaser forblevet attraktive: at mange brugere kan tilgå data via netværket.

In the 70s scientists formed the theory of relational databases (terms like: table, record, column (field) and relationality and many others). On the basis of this theory IBM DB2 and Oracle databases were created, which have been developed and used till today. In the late 70s the first PCs were constructed. Their users could (gradually) utilize many types of applications, including those for database construction.

When it comes to large databases in companies, the situation hasn't changed: they still require powerful computers or computer complexes called clusters. This goes, however, beyond the topic of this manual.

In the area of "accessible" databases with graphic user interface for PCs you can choose from the following:

  • DBase - a tool for databases operation for DOS popular in the 80s. Files in DBase format are still used in some specific cases due to their simplicity.
  • FoxPro - an application similar to DBase (early 90s). After being taken over by Microsoft, graphic user interfaces were introduced and therefore it is used for creating databases on PCs. This product is still offered, though seems a bit obsolete.
  • Microsoft Access - an application for databases (data and graphic interface design) with many simplifications, therefore suitable for beginners, designed in the late 80s, based on 16-Bit Architecture. This product is offered and widely used till today, especially by small companies, where efficiency and multiuser requirements are not very demanding.
  • FileMaker - popular application similar to MS Access in simplicity, operating on Windows and Macintosh platforms, offered since 1985.
  • Kexi - a multiplatform application (Unix/Linux, Windows, Mac OS X) designed in 2003, developed according to OpenSource principles, part of the global K Desktop Environment project, i.e. graphic environment for Unix/Linux systems. A significant contributor to Kexi's development is the OpenOffice Poland company.