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Fix path to initdb in installation instructions.

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General cleanup for 7.0.
This commit is contained in:
Thomas G. Lockhart
2000-04-07 13:30:58 +00:00
parent b2096a5512
commit 30e355fc80
11 changed files with 1233 additions and 896 deletions
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60
doc/src/sgml/advanced.sgml
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@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/advanced.sgml,v 1.9 2000/03/31 03:27:40 thomas Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/advanced.sgml,v 1.10 2000/04/07 13:30:58 thomas Exp $
-->
<chapter id="advanced">
@ -106,10 +106,10 @@ SELECT c.name, c.altitude
Here the <quote>*</quote> after cities indicates that the query should
be run over cities and all classes below cities in the
inheritance hierarchy. Many of the commands that we
have already discussed (<command>select</command>,
<command>update</command> and <command>delete</command>)
have already discussed (<command>SELECT</command>,
<command>UPDATE</command> and <command>DELETE</command>)
support this <quote>*</quote> notation, as do others, like
<command>alter</command>.
<command>ALTER</command>.
</para>
</sect1>
@ -118,7 +118,8 @@ SELECT c.name, c.altitude
<para>
One of the tenets of the relational model is that the
attributes of a relation are atomic. <productname>Postgres</productname> does not
attributes of a relation are atomic.
<productname>Postgres</productname> does not
have this restriction; attributes can themselves contain
sub-values that can be accessed from the query
language. For example, you can create attributes that
@ -129,7 +130,8 @@ SELECT c.name, c.altitude
<title>Arrays</title>
<para>
<productname>Postgres</productname> allows attributes of an instance to be defined
<productname>Postgres</productname> allows attributes of an
instance to be defined
as fixed-length or variable-length multi-dimensional
arrays. Arrays of any base type or user-defined type
can be created. To illustrate their use, we first create a
@ -149,11 +151,14 @@ CREATE TABLE SAL_EMP (
a <firstterm>text</firstterm> string (name), a one-dimensional
array of <firstterm>int4</firstterm>
(pay_by_quarter), which represents the employee's
salary by quarter and a two-dimensional array of <firstterm>text</firstterm>
salary by quarter and a two-dimensional array of
<firstterm>text</firstterm>
(schedule), which represents the employee's weekly
schedule. Now we do some <firstterm>INSERTS</firstterm>s; note that when
schedule. Now we do some <firstterm>INSERTS</firstterm>s;
note that when
appending to an array, we enclose the values within
braces and separate them by commas. If you know <firstterm>C</firstterm>,
braces and separate them by commas. If you know
<firstterm>C</firstterm>,
this is not unlike the syntax for initializing structures.
<programlisting>
@ -168,7 +173,8 @@ INSERT INTO SAL_EMP
'{{"talk", "consult"}, {"meeting"}}');
</programlisting>
By default, <productname>Postgres</productname> uses the "one-based" numbering
By default, <productname>Postgres</productname> uses the
"one-based" numbering
convention for arrays -- that is, an array of n elements
starts with array[1] and ends with array[n].
Now, we can run some queries on SAL_EMP. First, we
@ -228,6 +234,11 @@ SELECT SAL_EMP.schedule[1:2][1:1]
</sect2>
</sect1>
<!--
We haven't had Time Travel for two or three years, so let's stop
mentioning it. - thomas 2000-04-02
<sect1>
<title>Time Travel</title>
@ -240,21 +251,27 @@ SELECT SAL_EMP.schedule[1:2][1:1]
</para>
<para>
New features such as triggers allow one to mimic the behavior of time travel when desired, without
incurring the overhead when it is not needed (for most users, this is most of the time).
See examples in the <filename>contrib</filename> directory for more information.
New features such as triggers allow one to mimic the behavior of
time travel when desired, without
incurring the overhead when it is not needed (for most users, this
is most of the time).
See examples in the <filename>contrib</filename> directory for
more information.
</para>
<note>
<title>Time travel is deprecated</title>
<para>
The remaining text in this section is retained only until it can be rewritten in the context
of new techniques to accomplish the same purpose. Volunteers? - thomas 1998-01-12
The remaining text in this section is retained only until it can
be rewritten in the context
of new techniques to accomplish the same purpose.
Volunteers? - thomas 1998-01-12
</para>
</note>
<para>
<productname>Postgres</productname> supports the notion of time travel. This feature
<productname>Postgres</productname> supports the notion of time
travel. This feature
allows a user to run historical queries. For
example, to find the current population of Mariposa
city, one would query:
@ -269,7 +286,8 @@ SELECT * FROM cities WHERE name = 'Mariposa';
+---------+------------+----------+
</programlisting>
<productname>Postgres</productname> will automatically find the version of Mariposa's
<productname>Postgres</productname> will automatically find the
version of Mariposa's
record valid at the current time.
One can also give a time range. For example to see the
past and present populations of Mariposa, one would
@ -313,18 +331,22 @@ SELECT name, population
abbreviated as ``[,].''
</para>
</sect1>
-->
<sect1>
<title>More Advanced Features</title>
<para>
<productname>Postgres</productname> has many features not touched upon in this
<productname>Postgres</productname> has many features not touched
upon in this
tutorial introduction, which has been oriented toward newer users of
<acronym>SQL</acronym>.
These are discussed in more detail in both the User's and Programmer's Guides.
These are discussed in more detail in both the User's and
Programmer's Guides.
</para>
</sect1>
</chapter>
<!-- Keep this comment at the end of the file