84 lines
3.9 KiB
HTML
84 lines
3.9 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
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<HTML>
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<HEAD>
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<META NAME="GENERATOR" CONTENT="SGML-Tools 1.0.9">
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<TITLE>A mSQL and perl Web Server Mini HOWTO: Introduction</TITLE>
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<LINK HREF="WWW-mSQL-HOWTO-3.html" REL=next>
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<LINK HREF="WWW-mSQL-HOWTO-1.html" REL=previous>
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<LINK HREF="WWW-mSQL-HOWTO.html#toc2" REL=contents>
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</HEAD>
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<BODY>
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<A HREF="WWW-mSQL-HOWTO-3.html">Next</A>
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<A HREF="WWW-mSQL-HOWTO-1.html">Previous</A>
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<A HREF="WWW-mSQL-HOWTO.html#toc2">Contents</A>
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<HR>
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<H2><A NAME="s2">2. Introduction</A></H2>
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<P>It can be safely assumed that databases with a high volume of data
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or a complicated relational setup (like, perhaps, a lexical database
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for a living language) must be accessible to many users and operators
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at the same time. Ideally, it should be possible to use existing
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different hardware and software platforms that can be combined into
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the actual system. In order to reduce the implementation cost, only
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one system, the database server, needs to be powerful; the user stations
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typically just display data and accept user commands, but the processing
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is done on one machine only which led to the name client-server database.
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In addition, the user interface should be easy to maintain and
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should require as little as possible on the client side.
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<P>A system which meets these criteria can be built around the following
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items of protocols, concepts and software:
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<DL>
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<DT><B>Linux</B><DD><P>supplies the operating system. It is a stable Unix
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implementation providing true multi-user multi-tasking
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services with full network (TCP/IP e. a.) support.
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Except from the actual media and transmission cost, it
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is available free of charge and comes in form of
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so-called distributions which usually include everything
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needed from the basic OS to text processing, scripting,
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software development, interface builders, etc.
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<DT><B>HTML</B><DD><P>is the Hypertext Markup Language used to build
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interfaces to network systems like Intranets and the
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WWW, the World Wide Web. HTML is very simple and can be
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produced with any ASCII-capable text editor.
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<DT><B>Browsers</B><DD><P>are text-based (e. g. Lynx) or graphical
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(e. g. Mosaic, Netscape, Arena etc.) applications
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accepting, evaluating and displaying HTML documents.
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They are the only
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piece of software which is directly operated by the
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database user. Using browsers, it is possible
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to display various types of data (text, possibly images)
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and communicate with http servers (see next) on about
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every popular computer model for which a browser has
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been made available.
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<DT><B>http servers</B><DD><P>provide access to the area of a host
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computer where data intended for public use in a
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network are stored. They understand the http protocol
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and procure the information the user requests.
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<DT><B>SQL</B><DD><P>Structured Query Language is a language for manipulating
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data in relational databases. It has a very simple
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grammar and is a standard with wide industry support.
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SQL-based databases have become the core of the classical
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client/server database concept. There are many famous SQL
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systems available, like Oracle, Informix etc., and then
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there is also msql which comes with a very low or even
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zero price tag if it is used in academical and educational
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environments.
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<DT><B>CGI</B><DD><P>Common Gateway Interface is the programming interface
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between the system holding the data (in our case an
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SQL-based system) and the network protocol (HTML, of course).
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CGIs can be built around many programming
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languages, but a particularly popular language is perl.
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<DT><B>perl</B><DD><P>is an extremely powerful scripting language which
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combines all merits of C, various shell languages,
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and stream manipulation languages like awk and sed.
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Perl has a lot of modularized interfaces and can be used
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to control SQL databases, for example.
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</DL>
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<P>
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<HR>
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<A HREF="WWW-mSQL-HOWTO-3.html">Next</A>
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<A HREF="WWW-mSQL-HOWTO-1.html">Previous</A>
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<A HREF="WWW-mSQL-HOWTO.html#toc2">Contents</A>
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</BODY>
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</HTML>
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