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Add index. Only some parts of the manual set have index entries so far...

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This commit is contained in:
Peter Eisentraut
2001-05-12 22:51:36 +00:00
parent eedb7d18fa
commit 01839df6dd
29 changed files with 926 additions and 66 deletions
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84
doc/src/sgml/syntax.sgml
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@@ -1,10 +1,15 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/syntax.sgml,v 1.41 2001/02/25 16:05:21 petere Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/syntax.sgml,v 1.42 2001/05/12 22:51:35 petere Exp $
-->
<chapter id="sql-syntax">
<title>SQL Syntax</title>
<indexterm zone="sql-syntax">
<primary>syntax</primary>
<secondary>SQL</secondary>
</indexterm>
<abstract>
<para>
A description of the general syntax of SQL.
@@ -70,6 +75,15 @@ INSERT INTO MY_TABLE VALUES (3, 'hi there');
<sect2 id="sql-syntax-identifiers">
<title>Identifiers and Key Words</title>
<indexterm zone="sql-syntax-identifiers">
<primary>identifiers</primary>
</indexterm>
<indexterm zone="sql-syntax-identifiers">
<primary>key words</primary>
<secondary>syntax</secondary>
</indexterm>
<para>
Tokens such as <token>SELECT</token>, <token>UPDATE</token>, or
<token>VALUES</token> in the example above are examples of
@@ -107,6 +121,10 @@ INSERT INTO MY_TABLE VALUES (3, 'hi there');
</para>
<para>
<indexterm>
<primary>case sensitivity</primary>
<secondary>SQL commands</secondary>
</indexterm>
Identifier and key word names are case insensitive. Therefore
<programlisting>
UPDATE MY_TABLE SET A = 5;
@@ -123,6 +141,10 @@ UPDATE my_table SET a = 5;
</para>
<para>
<indexterm>
<primary>quotes</primary>
<secondary>and identifiers</secondary>
</indexterm>
There is a second kind of identifier: the <firstterm>delimited
identifier</firstterm> or <firstterm>quoted
identifier</firstterm>. It is formed by enclosing an arbitrary
@@ -173,6 +195,10 @@ UPDATE "my_table" SET "a" = 5;
<sect2 id="sql-syntax-constants">
<title>Constants</title>
<indexterm zone="sql-syntax-constants">
<primary>constants</primary>
</indexterm>
<para>
There are four kinds of <firstterm>implicitly typed
constants</firstterm> in <productname>Postgres</productname>:
@@ -186,7 +212,16 @@ UPDATE "my_table" SET "a" = 5;
<sect3 id="sql-syntax-strings">
<title>String Constants</title>
<indexterm zone="sql-syntax-strings">
<primary>character strings</primary>
<secondary>constants</secondary>
</indexterm>
<para>
<indexterm>
<primary>quotes</primary>
<secondary>escaping</secondary>
</indexterm>
A string constant in SQL is an arbitrary sequence of characters
bounded by single quotes (<quote>'</quote>), e.g., <literal>'This
is a string'</literal>. SQL allows single quotes to be embedded
@@ -237,6 +272,11 @@ SELECT 'foo' 'bar';
<sect3 id="sql-syntax-bit-strings">
<title>Bit String Constants</title>
<indexterm zone="sql-syntax-bit-strings">
<primary>bit strings</primary>
<secondary>constants</secondary>
</indexterm>
<para>
Bit string constants look like string constants with a
<literal>B</literal> (upper or lower case) immediately before the
@@ -264,6 +304,11 @@ SELECT 'foo' 'bar';
<sect3>
<title>Floating Point Constants</title>
<indexterm>
<primary>floating point</primary>
<secondary>constants</secondary>
</indexterm>
<para>
Floating point constants are accepted in these general forms:
<synopsis>
@@ -309,6 +354,11 @@ REAL '1.23' -- string style
<sect3 id="sql-syntax-constants-generic">
<title>Constants of Other Types</title>
<indexterm>
<primary>data types</primary>
<secondary>constants</secondary>
</indexterm>
<para>
A constant of an <emphasis>arbitrary</emphasis> type can be
entered using any one of the following notations:
@@ -351,6 +401,11 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> )
<sect3>
<title>Array constants</title>
<indexterm>
<primary>arrays</primary>
<secondary>constants</secondary>
</indexterm>
<para>
The general format of an array constant is the following:
<synopsis>
@@ -390,6 +445,11 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> )
<sect2 id="sql-syntax-operators">
<title>Operators</title>
<indexterm zone="sql-syntax-operators">
<primary>operators</primary>
<secondary>syntax</secondary>
</indexterm>
<para>
An operator is a sequence of up to <symbol>NAMEDATALEN</symbol>-1
(31 by default) characters from the following list:
@@ -524,6 +584,11 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> )
<sect2 id="sql-syntax-comments">
<title>Comments</title>
<indexterm zone="sql-syntax-comments">
<primary>comments</primary>
<secondary>in SQL</secondary>
</indexterm>
<para>
A comment is an arbitrary sequence of characters beginning with
double dashes and extending to the end of the line, e.g.:
@@ -562,11 +627,19 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> )
is either a user-defined column of a given table or one of the
following system-defined columns:
<indexterm>
<primary>columns</primary>
<secondary>system columns</secondary>
</indexterm>
<variablelist>
<varlistentry>
<term>oid</term>
<listitem>
<para>
<indexterm>
<primary>OID</primary>
</indexterm>
The unique identifier (object ID) of a row. This is a serial number
that is added by Postgres to all rows automatically. OIDs are not
reused and are 32-bit quantities.
@@ -841,6 +914,10 @@ sqrt(2)
<sect2 id="syntax-aggregates">
<title>Aggregate Expressions</title>
<indexterm zone="syntax-aggregates">
<primary>aggregate functions</primary>
</indexterm>
<para>
An <firstterm>aggregate expression</firstterm> represents the
application of an aggregate function across the rows selected by a
@@ -896,6 +973,11 @@ sqrt(2)
<sect1 id="sql-precedence">
<title>Lexical Precedence</title>
<indexterm zone="sql-precedence">
<primary>operators</primary>
<secondary>precedence</secondary>
</indexterm>
<para>
The precedence and associativity of the operators is hard-wired
into the parser. Most operators have the same precedence and are