|
1 |
| -<Chapter Id="intro"> |
2 |
| -<TITLE>Introduction</TITLE> |
3 |
| - |
4 |
| -<Para> |
5 |
| - This document is the user manual for the |
6 |
| - <Ulink url="http://postgresql.org/"><ProductName>PostgreSQL</ProductName></Ulink> |
7 |
| - database management system, originally developed at the University |
8 |
| - of California at Berkeley. |
9 |
| - |
10 |
| -<ProductName>PostgreSQL</ProductName> is based on |
11 |
| - <Ulink url="http://s2k-ftp.CS.Berkeley.EDU:8000/postgres/postgres.html"> |
12 |
| - <ProductName>Postgres release 4.2</ProductName></Ulink>. |
13 |
| -The <ProductName>Postgres</ProductName> project, |
14 |
| - led by Professor Michael Stonebraker, was sponsored by the |
15 |
| - Defense Advanced Research Projects Agency (<Acronym>DARPA</Acronym>), the |
16 |
| - Army Research Office (<Acronym>ARO</Acronym>), the National Science |
17 |
| - Foundation (<Acronym>NSF</Acronym>), and ESL, Inc. |
18 |
| -</Para> |
19 |
| - |
20 |
| -<Sect1> |
21 |
| -<Title> What is <ProductName>Postgres</ProductName>?</Title> |
22 |
| - |
23 |
| -<Para> |
24 |
| - Traditional relational database management systems |
25 |
| - (DBMSs) support a data model consisting of a collection |
26 |
| - of named relations, containing attributes of a specific |
27 |
| - type. In current commercial systems, possible types |
28 |
| - include floating point numbers, integers, character |
29 |
| - strings, money, and dates. It is commonly recognized |
30 |
| - that this model is inadequate for future data |
31 |
| - processing applications. |
32 |
| - The relational model successfully replaced previous |
33 |
| - models in part because of its "Spartan simplicity". |
34 |
| - However, as mentioned, this simplicity often makes the |
35 |
| - implementation of certain applications very difficult. |
36 |
| - <ProductName>Postgres</ProductName> offers substantial additional |
37 |
| - power by incorporating the following four additional |
38 |
| - basic concepts in such a way that users can easily |
39 |
| - extend the system: |
40 |
| - |
41 |
| -<SimpleList> |
42 |
| -<Member>classes</Member> |
43 |
| -<Member>inheritance</Member> |
44 |
| -<Member>types</Member> |
45 |
| -<Member>functions</Member> |
46 |
| -</SimpleList> |
47 |
| -</Para> |
48 |
| - |
49 |
| -<Para> |
50 |
| -Other features provide additional power and flexibility: |
51 |
| - |
52 |
| -<SimpleList> |
53 |
| -<Member>constraints</Member> |
54 |
| -<Member>triggers</Member> |
55 |
| -<Member>rules</Member> |
56 |
| -<Member>transaction integrity</Member> |
57 |
| -</SimpleList> |
58 |
| -</Para> |
59 |
| - |
60 |
| -<Para> |
61 |
| -These features put <ProductName>Postgres</ProductName> into the category of databases |
62 |
| -referred to as <FirstTerm>object-relational</FirstTerm>. Note that this is distinct |
63 |
| -from those referred to as <FirstTerm>object-oriented</FirstTerm>, which in general |
64 |
| -are not as well suited to supporting the traditional relational database languages. |
65 |
| -So, although <ProductName>Postgres</ProductName> has some object-oriented features, |
66 |
| -it is firmly in the relational database world. In fact, some commercial databases |
67 |
| -have recently incorporated features pioneered by <ProductName>Postgres</ProductName>. |
68 |
| -</Para> |
69 |
| - |
70 |
| -</Sect1> |
71 |
| - |
72 |
| -&history; |
73 |
| - |
74 |
| -&about; |
75 |
| - |
76 |
| -&info; |
77 |
| - |
78 |
| -¬ation; |
79 |
| - |
80 |
| -&y2k; |
81 |
| - |
82 |
| -&legal; |
83 |
| - |
84 |
| -</Chapter> |
| 1 | + <chapter id="intro"> |
| 2 | + <title>Introduction</title> |
| 3 | + |
| 4 | + <para> |
| 5 | + This document is the user manual for the |
| 6 | + <ulink url="http://postgresql.org/"><productname>PostgreSQL</productname></ulink> |
| 7 | + database management system, originally developed at the University |
| 8 | + of California at Berkeley. |
| 9 | + |
| 10 | + <productname>PostgreSQL</productname> is based on |
| 11 | + <ulink url="http://s2k-ftp.CS.Berkeley.EDU:8000/postgres/postgres.html"> |
| 12 | + <productname>Postgres release 4.2</productname></ulink>. |
| 13 | + The <productname>Postgres</productname> project, |
| 14 | + led by Professor Michael Stonebraker, was sponsored by the |
| 15 | + Defense Advanced Research Projects Agency (<acronym>DARPA</acronym>), the |
| 16 | + Army Research Office (<acronym>ARO</acronym>), the National Science |
| 17 | + Foundation (<acronym>NSF</acronym>), and ESL, Inc. |
| 18 | + </para> |
| 19 | + |
| 20 | + <sect1> |
| 21 | + <title> What is <productname>Postgres</productname>?</title> |
| 22 | + |
| 23 | + <para> |
| 24 | + Traditional relational database management systems |
| 25 | + (DBMSs) support a data model consisting of a collection |
| 26 | + of named relations, containing attributes of a specific |
| 27 | + type. In current commercial systems, possible types |
| 28 | + include floating point numbers, integers, character |
| 29 | + strings, money, and dates. It is commonly recognized |
| 30 | + that this model is inadequate for future data |
| 31 | + processing applications. |
| 32 | + The relational model successfully replaced previous |
| 33 | + models in part because of its "Spartan simplicity". |
| 34 | + However, as mentioned, this simplicity often makes the |
| 35 | + implementation of certain applications very difficult. |
| 36 | + <productname>Postgres</productname> offers substantial additional |
| 37 | + power by incorporating the following four additional |
| 38 | + basic concepts in such a way that users can easily |
| 39 | + extend the system: |
| 40 | + |
| 41 | + <simplelist> |
| 42 | + <member>classes</member> |
| 43 | + <member>inheritance</member> |
| 44 | + <member>types</member> |
| 45 | + <member>functions</member> |
| 46 | + </simplelist> |
| 47 | + </para> |
| 48 | + |
| 49 | + <para> |
| 50 | + Other features provide additional power and flexibility: |
| 51 | + |
| 52 | + <simplelist> |
| 53 | + <member>constraints</member> |
| 54 | + <member>triggers</member> |
| 55 | + <member>rules</member> |
| 56 | + <member>transaction integrity</member> |
| 57 | + </simplelist> |
| 58 | + </para> |
| 59 | + |
| 60 | + <para> |
| 61 | + These features put <productname>Postgres</productname> into the category of databases |
| 62 | + referred to as <firstterm>object-relational</firstterm>. Note that this is distinct |
| 63 | + from those referred to as <firstterm>object-oriented</firstterm>, which in general |
| 64 | + are not as well suited to supporting the traditional relational database languages. |
| 65 | + So, although <productname>Postgres</productname> has some object-oriented features, |
| 66 | + it is firmly in the relational database world. In fact, some commercial databases |
| 67 | + have recently incorporated features pioneered by <productname>Postgres</productname>. |
| 68 | + </para> |
| 69 | + |
| 70 | + </sect1> |
| 71 | + |
| 72 | + &history; |
| 73 | + &about; |
| 74 | + &info; |
| 75 | + ¬ation; |
| 76 | + &y2k; |
| 77 | + &legal; |
| 78 | + |
| 79 | + </chapter> |
| 80 | + |
| 81 | +<!-- Keep this comment at the end of the file |
| 82 | +Local variables: |
| 83 | +mode: sgml |
| 84 | +sgml-omittag:nil |
| 85 | +sgml-shorttag:t |
| 86 | +sgml-minimize-attributes:nil |
| 87 | +sgml-always-quote-attributes:t |
| 88 | +sgml-indent-step:1 |
| 89 | +sgml-indent-data:t |
| 90 | +sgml-parent-document:nil |
| 91 | +sgml-default-dtd-file:"./reference.ced" |
| 92 | +sgml-exposed-tags:nil |
| 93 | +sgml-local-catalogs:"/usr/lib/sgml/CATALOG" |
| 94 | +sgml-local-ecat-files:nil |
| 95 | +End: |
| 96 | +--> |
0 commit comments