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diff --git a/doc/src/sgml/intro.sgml b/doc/src/sgml/intro.sgml new file mode 100644 index 00000000000..09a6ad3b02b --- /dev/null +++ b/doc/src/sgml/intro.sgml @@ -0,0 +1,482 @@ +<Chapter> +<TITLE>Introduction</TITLE> + +<Para> + This document is the user manual for the + <Ulink url="http://postgresql.org/"><ProductName>PostgreSQL</ProductName></Ulink> + database management system, originally developed at the University + of California at Berkeley. <ProductName>PostgreSQL</ProductName> is based on + <Ulink url="http://s2k-ftp.CS.Berkeley.EDU:8000/postgres/postgres.html"> + <ProductName>Postgres release 4.2</ProductName></Ulink>. +The <ProductName>Postgres</ProductName> project, + led by Professor Michael Stonebraker, has been sponsored by the + Defense Advanced Research Projects Agency (<Acronym>DARPA</Acronym>), the + Army Research Office (<Acronym>ARO</Acronym>), the National Science + Foundation (<Acronym>NSF</Acronym>), and ESL, Inc. +</Para> + +<Sect1> +<Title> What is <ProductName>Postgres</ProductName>?</Title> + +<Para> + Traditional relational database management systems + (DBMSs) support a data model consisting of a collection + of named relations, containing attributes of a specific + type. In current commercial systems, possible types + include floating point numbers, integers, character + strings, money, and dates. It is commonly recognized + that this model is inadequate for future data + processing applications. + The relational model successfully replaced previous + models in part because of its "Spartan simplicity". + However, as mentioned, this simplicity often makes the + implementation of certain applications very difficult. + <ProductName>Postgres</ProductName> offers substantial additional + power by incorporating the following four additional + basic concepts in such a way that users can easily + extend the system: + +<SimpleList> +<Member>classes</Member> +<Member>inheritance</Member> +<Member>types</Member> +<Member>functions</Member> +</SimpleList> +</Para> + +<Para> +Other features provide additional power and flexibility: + +<SimpleList> +<Member>constraints</Member> +<Member>triggers</Member> +<Member>rules</Member> +<Member>transaction integrity</Member> +</SimpleList> +</Para> + +<Para> +These features put <ProductName>Postgres</ProductName> into the category of databases +referred to as <FirstTerm>object-relational</FirstTerm>. Note that this is distinct +from those referred to as <FirstTerm>object-oriented</FirstTerm>, which in general +are not as well suited to supporting the traditional relational database languages. +So, although <ProductName>Postgres</ProductName> has some object-oriented features, +it is firmly in the relational database world. In fact, some commercial databases +have recently incorporated features pioneered by <ProductName>Postgres</ProductName>. + +</Sect1> + +<Sect1> +<Title>A Short History of <ProductName>Postgres</ProductName></Title> + +<Sect2> +<Title>The Berkeley <ProductName>Postgres</ProductName> Project</Title> + +<Para> + Implementation of the <ProductName>Postgres</ProductName> <Acronym>DBMS</Acronym> began in 1986. The + initial concepts for the system were presented in +<!-- +<XRef LinkEnd="STON86"> +--> +<Citation>[STON86]</Citation> + and the definition of the initial data model + appeared in +<!-- +<XRef LinkEnd="ROWE87">. +--> +<Citation>[ROWE87]</Citation>. +The design of the rule system at + that time was described in +<!-- +<XRef LinkEnd="STON87a">. +--> +<Citation>[STON87a]</Citation>. +The rationale + and architecture of the storage manager were detailed in +<!-- +<XRef LinkEnd="STON87b">. +--> +<Citation>[STON87b]</Citation>. +</Para> + +<Para> + <ProductName>Postgres</ProductName> has undergone several major releases since + then. The first "demoware" system became operational + in 1987 and was shown at the 1988 <Acronym>ACM-SIGMOD</Acronym> + Conference. We released Version 1, described in +<!-- +<XRef LinkEnd="STON90a">, +--> +<Citation>[STON90a]</Citation>, + to a few external users in June 1989. In response to a + critique of the first rule system +<!-- +(<XRef LinkEnd="STON89">), +--> +(<Citation>[STON89]</Citation>), +the rule + system was redesigned +<!-- +(<XRef LinkEnd="STON90b">) +--> +(<Citation>[STON90b]</Citation>) +and Version 2 was + released in June 1990 with the new rule system. + Version 3 appeared in 1991 and added support for multiple + storage managers, an improved query executor, and a + rewritten rewrite rule system. For the most part, + releases since then have focused on portability and + reliability. +</Para> + +<Para> + <ProductName>Postgres</ProductName> has been used to implement many different + research and production applications. These include: a + financial data analysis system, a jet engine + performance monitoring package, an asteroid tracking + database, a medical information database, and several + geographic information systems. <ProductName>Postgres</ProductName> has also been + used as an educational tool at several universities. + Finally, <Ulink url="http://www.illustra.com/">Illustra Information Technologies</Ulink> picked up + the code and commercialized it. + <ProductName>Postgres</ProductName> became the primary data manager for the + <Ulink url="http://www.sdsc.edu/0/Parts_Collabs/S2K/s2k_home.html">Sequoia 2000</Ulink> + scientific computing project in late 1992. + Furthermore, the size of the external user community + nearly doubled during 1993. It became increasingly + obvious that maintenance of the prototype code and + support was taking up large amounts of time that should + have been devoted to database research. In an effort + to reduce this support burden, the project officially + ended with Version 4.2. +</Para> +</Sect2> + +<Sect2> +<Title><ProductName>Postgres95</ProductName></Title> + +<Para> +In 1994, +<ULink url="mailto:ayu@informix.com">Andrew Yu</ULink> +and +<ULink url="http://http.cs.berkeley.edu/~jolly/">Jolly Chen</ULink> +added a SQL language interpreter to <ProductName>Postgres</ProductName>, and the code was subsequently released to +the Web to find its own way in the world. <ProductName>Postgres95</ProductName> was a public-domain, open source descendant +of this original Berkeley code. +</Para> + +<Para> + <ProductName>Postgres95</ProductName> is a derivative of the last official release + of <ProductName>Postgres</ProductName> (version 4.2). The code is now completely + ANSI C and the code size has been trimmed by 25%. There + are a lot of internal changes that improve performance + and code maintainability. <ProductName>Postgres95</ProductName> v1.0.x runs about 30-50% + faster on the Wisconsin Benchmark compared to v4.2. + Apart from bug fixes, these are the major enhancements: + +<ItemizedList> +<ListItem> +<Para> + The query language <ProductName>Postquel</ProductName> has been replaced with + <Acronym>SQL</Acronym> (implemented in the server). We do not yet support + subqueries (which can be imitated with user defined + <Acronym>SQL</Acronym> functions). Aggregates have been + re-implemented. We also added support for ``GROUP BY''. + The <FileName>libpq</FileName> interface is still available for <Acronym>C</Acronym> + programs. +</Para> +</ListItem> +<ListItem> +<Para> + In addition to the monitor program, we provide a new + program (<Application>psql</Application>) which supports <Acronym>GNU</Acronym> <FileName>readline</FileName>. +</Para> +</ListItem> +<ListItem> +<Para> + We added a new front-end library, <FileName>libpgtcl</FileName>, that + supports <Acronym>Tcl</Acronym>-based clients. A sample shell, + pgtclsh, provides new Tcl commands to interface <Application>tcl</Application> + programs with the <ProductName>Postgres95</ProductName> backend. +</Para> +</ListItem> +<ListItem> +<Para> + The large object interface has been overhauled. We + kept Inversion large objects as the only mechanism + for storing large objects. (This is not to be + confused with the Inversion file system which has been + removed.) +</Para> +</ListItem> +<ListItem> +<Para> + The instance-level rule system has been removed. + Rules are still available as rewrite rules. +</Para> +</ListItem> +<ListItem> +<Para> + A short tutorial introducing regular <Acronym>SQL</Acronym> features as + well as those of ours is distributed with the source + code. +</Para> +</ListItem> +<ListItem> +<Para> + <Acronym>GNU</Acronym> make (instead of <Acronym>BSD</Acronym> make) is used for the + build. Also, <ProductName>Postgres95</ProductName> can be compiled with an + unpatched <ProductName>gcc</ProductName> (data alignment of doubles has been + fixed). +</Para> +</ListItem> +</ItemizedList> +</Para> +</Sect2> + +<Sect2> +<Title><ProductName>PostgreSQL</ProductName></Title> + +<Para> +By 1996, it became clear that the name <Quote>Postgres95</Quote> would not stand +the test of time. A new name, <ProductName>PostgreSQL</ProductName>, was chosen to reflect the +relationship between original <ProductName>Postgres</ProductName> and the more recent +versions with <Acronym>SQL</Acronym> capability. At the same time, the version numbering +was reset to start at 6.0, putting the numbers back into the sequence originally begun by +the <ProductName>Postgres</ProductName> Project. + +<Para> +The emphasis on development for the v1.0.x releases of <ProductName>Postgres95</ProductName> +was on stabilizing the backend code. +With the v6.x series of <ProductName>PostgreSQL</ProductName>, the emphasis has shifted from +identifying and understanding existing problems in the backend to augmenting features and capabilities, although +work continues in all areas. + +<Para> +Major enhancements include: + +<ItemizedList> +<ListItem> +<Para> +Important backend features, including subselects, defaults, constraints, and triggers, have been implemented. +</Para> +</ListItem> +<ListItem> +<Para> +Additional <Acronym>SQL92</Acronym>-compliant language features have been added, + including primary keys, quoted identifiers, literal string type coersion, type casting, + and binary and hexadecimal integer input. +</Para> +</ListItem> +<ListItem> +<Para> +Built-in types have been improved, including new wide-range date/time types and additional geometric type support. +</Para> +</ListItem> +<ListItem> +<Para> +Overall backend code speed has been increased by approximately 20%, and backend startup speed has decreased 80%. +</Para> +</ListItem> +</ItemizedList> +</Para> +</Sect2> + +<Sect1> +<Title>About This Release</Title> + +<Para> + From now on, We will use <ProductName>Postgres</ProductName> to mean <ProductName>PostgreSQL</ProductName>. + +<Para> + <ProductName>PostgreSQL</ProductName> is available without cost. This manual + describes version 6.3 of <ProductName>PostgreSQL</ProductName>. + +<Para> +Check the Administrator's Guide for a list of currently supported machines. In general, +<ProductName>PostgreSQL</ProductName> is portable to any Unix/Posix-compatible system +with full libc library support. + +</Sect1> + +<Sect1> +<Title>Resources</Title> + +<Para> +This manual set is organized into several parts: + +<VariableList> +<VarListEntry> +<Term>Tutorial</Term> +<ListItem> +<Para> +An introduction for new users. Does not cover advanced features. +</Para> +</ListItem> +</VarListEntry> + +<VarListEntry> +<Term>User's Guide</Term> +<ListItem> +<Para> +General information for users, including available commands and data types. +</Para> +</ListItem> +</VarListEntry> + +<VarListEntry> +<Term>Programmer's Guide</Term> +<ListItem> +<Para> +Advanced information for application programmers. Topics include +type and function extensibility, library interfaces, and application design issues. +</Para> +</ListItem> +</VarListEntry> + +<VarListEntry> +<Term>Administrator's Guide</Term> +<ListItem> +<Para> +Installation and management information. List of supported machines. +</Para> +</ListItem> +</VarListEntry> + +<VarListEntry> +<Term>Developer's Guide</Term> +<ListItem> +<Para> +Information for <ProductName>Postgres</ProductName> developers. This is intended +for those who are contributing to the <ProductName>Postgres</ProductName> +project; application development information should appear in the Programmer's Guide. +</Para> +</ListItem> +</VarListEntry> + +<VarListEntry> +<Term>Reference Manual</Term> +<ListItem> +<Para> +Detailed reference information on command syntax. +At the moment, this manual is very sparse, but eventually should contain +information similar to that in the man pages. +</Para> +</ListItem> +</VarListEntry> +</VariableList> + +<Para> +In addition to this manual set, there are other resources to help you with +<ProductName>Postgres</ProductName> installation and use: + +<VariableList> +<VarListEntry> +<Term>man pages</Term> +<ListItem> +<Para> +The man pages have general information on command syntax. +</Para> +</ListItem> +</VarListEntry> + +<VarListEntry> +<Term>FAQs</Term> +<ListItem> +<Para> +The Frequently Asked Questions (FAQ) documents address both general issues +and some platform-specific issues. +</Para> +</ListItem> +</VarListEntry> + +<VarListEntry> +<Term>READMEs</Term> +<ListItem> +<Para> +README files are available for some contributed packages. +</Para> +</ListItem> +</VarListEntry> + +<VarListEntry> +<Term>Web Site</Term> +<ListItem> +<Para> +The <ULink url="postgresql.org"><ProductName>Postgres</ProductName></ULink> web site has some information +not appearing in the distribution. There is a <ProductName>mhonarc</ProductName> catalog of mailing list traffic +which is a rich resource for many topics. +</Para> +</ListItem> +</VarListEntry> + +<VarListEntry> +<Term>Mailing Lists</Term> +<ListItem> +<Para> +The <ULink url="mailto:questions@postgresql.org"><ProductName>Postgres</ProductName> Questions</ULink> +mailing list is a good place to have user questions answered. Other mailing lists are available; consult +the web page for details. +</Para> +</ListItem> +</VarListEntry> + +<VarListEntry> +<Term>Yourself!</Term> +<ListItem> +<Para> +<ProductName>Postgres</ProductName> is an open source product. As such, it depends on the user community for +ongoing support. As you begin to use <ProductName>Postgres</ProductName>, you will rely on others +for help, either through the documentation or through the mailing lists. Consider contributing your +knowledge back. If you learn something which is not in the documentation, write it up and contribute it. +If you add features to the code, contribute it. Even those without a lot of experience can provide +corrections and minor changes in the documentation, and that is a good way to start. +The <ULink url="mailto:docs@postgresql.org"><ProductName>Postgres</ProductName> Documentation</ULink> +mailing list is the place to get going. +</Para> +</ListItem> +</VarListEntry> +</VariableList> + +</Sect1> + +<Sect1> +<Title>Copyrights and Trademarks</Title> + +<Para> +<ProductName>PostgreSQL</ProductName> is copyright (C) 1996-8 by the PostgreSQL Global Development Group, +and is distributed under the terms of the Berkeley license. + +<Para> +<ProductName>Postgres95</ProductName> is copyright (C) 1994-5 by the Regents of the University of California. +Permission to use, copy, modify, and distribute this software and its documentation +for any purpose, without fee, and without a written agreement is hereby granted, +provided that the above copyright notice and this paragraph and the following two +paragraphs appear in all copies. +</Para> +<Para> +In no event shall the University of California be liable to +any party for direct, indirect, special, incidental, or consequential +damages, including lost profits, arising out of the use of this +software and its documentation, even if the University of California +has been advised of the possibility of such damage. +</Para> +<Para> +The University of California specifically disclaims any +warranties, including, but not limited to, the implied warranties +of merchantability and fitness for a particular purpose. +The software provided hereunder is on an "as-is" basis, and +the University of California has no obligations to provide +maintainance, support, updates, enhancements, or modifications. +</Para> + +<Para> +<Acronym>UNIX</Acronym> is a trademark of X/Open, Ltd. Sun4, SPARC, SunOS +and Solaris are trademarks of Sun Microsystems, Inc. DEC, +DECstation, Alpha AXP and ULTRIX are trademarks of Digital +Equipment Corp. PA-RISC and HP-UX are trademarks of +Hewlett-Packard Co. OSF/1 is a trademark of the Open +Software Foundation. +</Para> + +</Chapter> |