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Postgres FD Implementation
Commit 95e3cec6 authored by Thomas G. Lockhart's avatar Thomas G. Lockhart
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Include mention of CASE, COALESCE, and IFNULL. 

Add date/time parsing procedure (perhaps should be in appendix).
Add time zone information (ditto).
Update keyword list.
parent 5dd715b5
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doc/src/sgml/admin.sgml
View file @ 95e3cec6
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/Attic/admin.sgml,v 1.11 1999/05/04 02:16:57 thomas Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/Attic/admin.sgml,v 1.12 1999/05/12 07:32:42 thomas Exp $
Postgres Administrator's Guide.
Derived from postgres.sgml.
- thomas 1998-10-27
$Log: admin.sgml,v $
Revision 1.11 1999/05/04 02:16:57 thomas
Include chapter on security.
Revision 1.12 1999/05/12 07:32:42 thomas
Include mention of CASE, COALESCE, and IFNULL.
Add date/time parsing procedure (perhaps should be in appendix).
Add time zone information (ditto).
Update keyword list.
Revision 1.10 1999/01/19 16:06:25 thomas
Merge current.sgml into release.sgml so all release notes are in the same
......@@ -59,8 +62,8 @@ Bigger updates to the installation instructions (install and config).
<!-- Title information -->
<Title>PostgreSQL Administrator's Guide</Title>
<BookInfo>
<Title>PostgreSQL Administrator's Guide</Title>
<BookInfo>
<ReleaseInfo>Covering v6.4 for general release</ReleaseInfo>
<BookBiblio>
<AuthorGroup>
......@@ -84,17 +87,17 @@ Bigger updates to the installation instructions (install and config).
<AuthorInitials>TGL</AuthorInitials>
-->
<Date>(last updated 1998-10-27)</Date>
<Date>(last updated 1999-04-08)</Date>
</BookBiblio>
<LegalNotice>
<Para>
<ProductName>PostgreSQL</ProductName> is copyright (C) 1998
by the Postgres Global Development Group.
</Para>
</LegalNotice>
<LegalNotice>
<Para>
<ProductName>PostgreSQL</ProductName> is copyright (C) 1998-9
by the Postgres Global Development Group.
</Para>
</LegalNotice>
</BookInfo>
</BookInfo>
<!--
<TOC> </TOC>
......@@ -109,36 +112,36 @@ Your name here...
</Dedication>
-->
<Preface id="preface">
<Title>Summary</Title>
<Preface id="preface">
<Title>Summary</Title>
<Para>
<ProductName>Postgres</ProductName>,
<Para>
<ProductName>Postgres</ProductName>,
developed originally in the UC Berkeley Computer Science Department,
pioneered many of the object-relational concepts
now becoming available in some commercial databases.
It provides SQL92/SQL3 language support,
It provides SQL92/SQL3 language support,
transaction integrity, and type extensibility.
<ProductName>PostgreSQL</ProductName> is a public-domain, open source descendant
of this original Berkeley code.
</Para>
</Preface>
&intro-ag;
&ports;
&config;
&install;
&installw;
&runtime;
&security;
&options;
&start-ag;
&recovery;
&regress;
&release;
&biblio;
</Para>
</Preface>
&intro-ag;
&ports;
&config;
&install;
&installw;
&runtime;
&security;
&options;
&start-ag;
&recovery;
&regress;
&release;
&biblio;
<!--
Don't bother with an index until we get some index entries.
......
doc/src/sgml/biblio.sgml
View file @ 95e3cec6
......@@ -2,7 +2,8 @@
<title>Bibliography</title>
<para>
Selected references and readings for <acronym>SQL</acronym> and <productname>Postgres</productname>.
Selected references and readings for <acronym>SQL</acronym>
and <productname>Postgres</productname>.
</para>
<bibliodiv>
......
doc/src/sgml/datatype.sgml
View file @ 95e3cec6
<chapter id="datatype">
<title>Data Types</title>
<chapter id="datatype">
<title>Data Types</title>
<abstract>
<para>
Describes the built-in data types available in
<productname>Postgres</productname>.
</para>
</abstract>
<abstract>
<para>
Describes the built-in data types available in
<productname>Postgres</productname>.
</para>
</abstract>
<para>
<productname>Postgres</productname> has a rich set of native data
types available to users.
Users may add new types to <productname>Postgres</productname> using the
<command>DEFINE TYPE</command>
command described elsewhere.
</para>
<para>
<productname>Postgres</productname> has a rich set of native data
types available to users.
Users may add new types to <productname>Postgres</productname> using the
<command>DEFINE TYPE</command>
command described elsewhere.
</para>
<para>
In the context of data types, the following sections will discuss
<acronym>SQL</acronym> standards compliance, porting issues, and usage.
Some <productname>Postgres</productname> types correspond directly to
<acronym>SQL92</acronym>-compatible types. In other
cases, data types defined by <acronym>SQL92</acronym> syntax are mapped directly
into native <productname>Postgres</productname> types.
Many of the built-in types have obvious external formats. However, several
types are either unique to <productname>Postgres</productname>,
such as open and closed paths, or have
several possibilities for formats, such as the date and time types.
</para>
<para>
In the context of data types, the following sections will discuss
<acronym>SQL</acronym> standards compliance, porting issues, and usage.
Some <productname>Postgres</productname> types correspond directly to
<acronym>SQL92</acronym>-compatible types. In other
cases, data types defined by <acronym>SQL92</acronym> syntax are mapped directly
into native <productname>Postgres</productname> types.
Many of the built-in types have obvious external formats. However, several
types are either unique to <productname>Postgres</productname>,
such as open and closed paths, or have
several possibilities for formats, such as the date and time types.
</para>
<para>
<table tocentry="1">
<title><productname>Postgres</productname> Data Types</title>
<titleabbrev>Data Types</titleabbrev>
<tgroup cols="3">
<thead>
<para>
<table tocentry="1">
<title><productname>Postgres</productname> Data Types</title>
<titleabbrev>Data Types</titleabbrev>
<tgroup cols="3">
<thead>
<row>
<entry><productname>Postgres</productname> Type</entry>
<entry><acronym>SQL92</acronym> or <acronym>SQL3</acronym> Type</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
</thead>
<tbody>
<row>
<entry>bool</entry>
<entry>boolean</entry>
......@@ -169,32 +169,32 @@ several possibilities for formats, such as the date and time types.
<entry>character varying(n)</entry>
<entry>variable-length character string</entry>
</row>
</tbody>
</tgroup>
</table>
</para>
</tbody>
</tgroup>
</table>
</para>
<para>
<note>
<para>
The <type>cidr</type> and <type>inet</type> types are designed to handle any IP type
but only ipv4 is handled in the current implementation.
Everything here that talks about ipv4 will apply to ipv6 in a future release.</para>
</note></para>
<para>
<note>
<para>
The <type>cidr</type> and <type>inet</type> types are designed to handle any IP type
but only ipv4 is handled in the current implementation.
Everything here that talks about ipv4 will apply to ipv6 in a future release.</para>
</note></para>
<para>
<table tocentry="1">
<title><productname>Postgres</productname> Function Constants</title>
<titleabbrev>Constants</titleabbrev>
<tgroup cols="3">
<thead>
<para>
<table tocentry="1">
<title><productname>Postgres</productname> Function Constants</title>
<titleabbrev>Constants</titleabbrev>
<tgroup cols="3">
<thead>
<row>
<entry><productname>Postgres</productname> Function</entry>
<entry><acronym>SQL92</acronym> Constant</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
</thead>
<tbody>
<row>
<entry>getpgusername()</entry>
<entry>current_user</entry>
......@@ -215,57 +215,57 @@ Everything here that talks about ipv4 will apply to ipv6 in a future release.</p
<entry>current_timestamp</entry>
<entry>date and time of current transaction</entry>
</row>
</tbody>
</tgroup>
</table>
</para>
</tbody>
</tgroup>
</table>
</para>
<para>
<productname>Postgres</productname> has features at the forefront of
<acronym>ORDBMS</acronym> development. In addition to
<acronym>SQL3</acronym> conformance, substantial portions
of <acronym>SQL92</acronym> are also supported.
Although we strive for <acronym>SQL92</acronym> compliance,
there are some aspects of the standard
which are ill considered and which should not live through subsequent standards.
<productname>Postgres</productname> will not make great efforts to
conform to these features; however, these tend to apply in little-used
or obsure cases, and a typical user is not likely to run into them.</para>
<para>
<productname>Postgres</productname> has features at the forefront of
<acronym>ORDBMS</acronym> development. In addition to
<acronym>SQL3</acronym> conformance, substantial portions
of <acronym>SQL92</acronym> are also supported.
Although we strive for <acronym>SQL92</acronym> compliance,
there are some aspects of the standard
which are ill considered and which should not live through subsequent standards.
<productname>Postgres</productname> will not make great efforts to
conform to these features; however, these tend to apply in little-used
or obsure cases, and a typical user is not likely to run into them.</para>
<para>
Most of the input and output functions corresponding to the
base types (e.g., integers and floating point numbers) do some
error-checking.
Some of the operators and functions (e.g.,
addition and multiplication) do not perform run-time error-checking in the
interests of improving execution speed.
On some systems, for example, the numeric operators for some data types may
silently underflow or overflow.
</para>
<para>
Most of the input and output functions corresponding to the
base types (e.g., integers and floating point numbers) do some
error-checking.
Some of the operators and functions (e.g.,
addition and multiplication) do not perform run-time error-checking in the
interests of improving execution speed.
On some systems, for example, the numeric operators for some data types may
silently underflow or overflow.
</para>
<para>
Note that some of the input and output functions are not invertible. That is,
the result of an output function may lose precision when compared to
the original input.
<para>
Note that some of the input and output functions are not invertible. That is,
the result of an output function may lose precision when compared to
the original input.
<note>
<para>
The original <productname>Postgres</productname> v4.2 code received from
Berkeley rounded all double precision floating point results to six digits for
output. Starting with v6.1, floating point numbers are allowed to retain
most of the intrinsic precision of the type (typically 15 digits for doubles,
6 digits for 4-byte floats).
Other types with underlying floating point fields (e.g. geometric
types) carry similar precision.</para>
</note>
</para>
<note>
<para>
The original <productname>Postgres</productname> v4.2 code received from
Berkeley rounded all double precision floating point results to six digits for
output. Starting with v6.1, floating point numbers are allowed to retain
most of the intrinsic precision of the type (typically 15 digits for doubles,
6 digits for 4-byte floats).
Other types with underlying floating point fields (e.g. geometric
types) carry similar precision.</para>
</note>
</para>
<sect1>
<title>Numeric Types</title>
<sect1>
<title>Numeric Types</title>
<para>
Numeric types consist of two- and four-byte integers and four- and eight-byte
floating point numbers.</para>
<para>
Numeric types consist of two- and four-byte integers and four- and eight-byte
floating point numbers.</para>
<para>
<table tocentry="1">
......
doc/src/sgml/func.sgml
View file @ 95e3cec6
<Chapter Id="functions">
<Title>Functions</Title>
<Chapter Id="functions">
<Title id="functions-title">Functions</Title>
<Abstract>
<Para>
Describes the built-in functions available in <ProductName>Postgres</ProductName>.
</Para>
</Abstract>
<Abstract>
<Para>
Describes the built-in functions available in <ProductName>Postgres</ProductName>.
</Para>
</Abstract>
<Para>
Many data types have functions available for conversion to other related types.
In addition, there are some type-specific functions. Some functions are also
available through operators and may be documented as operators only.
</Para>
<sect1>
<title id="sql-funcs">SQL Functions</title>
<para>
<quote><acronym>SQL</acronym> functions</quote> are constructs
defined by the <acronym>SQL92</acronym> standard which have
function-like syntax but which can not be implemented as simple
functions.
</para>
<Para>
Many data types have functions available for conversion to other related types.
In addition, there are some type-specific functions. Some functions are also
available through operators and may be documented as operators only.
</Para>
<para>
<TABLE TOCENTRY="1">
<TITLE>SQL Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<ROW>
<ENTRY>Function</ENTRY>
<ENTRY>Returns</ENTRY>
<ENTRY>Description</ENTRY>
<ENTRY>Example</ENTRY>
</ROW>
</THEAD>
<TBODY>
<ROW>
<ENTRY> COALESCE(<replaceable class="parameter">list</replaceable>) </ENTRY>
<ENTRY> non-NULL </ENTRY>
<ENTRY> return first non-NULL value in list </ENTRY>
<ENTRY> COALESCE(<replaceable class="parameter">c1</replaceable>, <replaceable class="parameter">c2</replaceable> + 5, 0) </ENTRY>
</ROW>
<ROW>
<ENTRY> IFNULL(<replaceable
class="parameter">input</replaceable>,<replaceable> class="parameter">non-NULL substitute</replaceable>) </ENTRY>
<ENTRY> non-NULL </ENTRY>
<ENTRY> return second argument if first is NULL </ENTRY>
<ENTRY> IFNULL(<replaceable class="parameter">c1</replaceable>, 'N/A')</ENTRY>
</ROW>
<ROW>
<ENTRY> CASE(WHEN <replaceable class="parameter">expr</replaceable> THEN <replaceable class="parameter">expr</replaceable> [...] ELSE <replaceable class="parameter">expr</replaceable> ) </ENTRY>
<ENTRY> <replaceable class="parameter">expr</replaceable> </ENTRY>
<ENTRY> return expression for first true clause </ENTRY>
<ENTRY> CASE(WHEN <replaceable class="parameter">c1</replaceable> = 1 THEN 'match' ELSE 'no match') </ENTRY>
</ROW>
</tbody>
</tgroup>
</table>
</para>
</sect1>
<sect1>
<title id="math-funcs">Mathematical Functions</title>
<sect1>
<title id="math-funcs">Mathematical Functions</title>
<Para>
<TABLE TOCENTRY="1">
<TITLE>Mathematical Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<Para>
<TABLE TOCENTRY="1">
<TITLE>Mathematical Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<ROW>
<ENTRY>Function</ENTRY>
<ENTRY>Returns</ENTRY>
<ENTRY>Description</ENTRY>
<ENTRY>Example</ENTRY>
</ROW>
</THEAD>
<TBODY>
</THEAD>
<TBODY>
<ROW>
<ENTRY> dexp(float8) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> raise e to the specified exponent </ENTRY>
<ENTRY> dexp(2.0) </ENTRY>
<ENTRY> dexp(float8) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> raise e to the specified exponent </ENTRY>
<ENTRY> dexp(2.0) </ENTRY>
</ROW>
<ROW>
<ENTRY> dpow(float8,float8) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> raise a number to the specified exponent </ENTRY>
<ENTRY> dpow(2.0, 16.0) </ENTRY>
<ENTRY> dpow(float8,float8) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> raise a number to the specified exponent </ENTRY>
<ENTRY> dpow(2.0, 16.0) </ENTRY>
</ROW>
<ROW>
<ENTRY> float(int) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> convert integer to floating point </ENTRY>
<ENTRY> float(2) </ENTRY>
<ENTRY> float(int) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> convert integer to floating point </ENTRY>
<ENTRY> float(2) </ENTRY>
</ROW>
<ROW>
<ENTRY> float4(int) </ENTRY>
<ENTRY> float4 </ENTRY>
<ENTRY> convert integer to floating point </ENTRY>
<ENTRY> float4(2) </ENTRY>
<ENTRY> float4(int) </ENTRY>
<ENTRY> float4 </ENTRY>
<ENTRY> convert integer to floating point </ENTRY>
<ENTRY> float4(2) </ENTRY>
</ROW>
<ROW>
<ENTRY> integer(float) </ENTRY>
<ENTRY> int </ENTRY>
<ENTRY> convert floating point to integer </ENTRY>
<ENTRY> integer(2.0) </ENTRY>
<ENTRY> integer(float) </ENTRY>
<ENTRY> int </ENTRY>
<ENTRY> convert floating point to integer </ENTRY>
<ENTRY> integer(2.0) </ENTRY>
</ROW>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</sect1>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</sect1>
<sect1>
<title>String Functions</title>
......@@ -146,573 +194,574 @@ available through operators and may be documented as operators only.
Some are used internally to implement the SQL92 string functions listed above.
</Para>
<Para>
<TABLE TOCENTRY="1">
<TITLE>String Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<Para>
<TABLE TOCENTRY="1">
<TITLE>String Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<ROW>
<ENTRY>Function</ENTRY>
<ENTRY>Returns</ENTRY>
<ENTRY>Description</ENTRY>
<ENTRY>Example</ENTRY>
</ROW>
</THEAD>
<TBODY>
</THEAD>
<TBODY>
<ROW>
<ENTRY> char(text) </ENTRY>
<ENTRY> char </ENTRY>
<ENTRY> convert text to char type </ENTRY>
<ENTRY> char('text string') </ENTRY>
<ENTRY> char(text) </ENTRY>
<ENTRY> char </ENTRY>
<ENTRY> convert text to char type </ENTRY>
<ENTRY> char('text string') </ENTRY>
</ROW>
<ROW>
<ENTRY> char(varchar) </ENTRY>
<ENTRY> char </ENTRY>
<ENTRY> convert varchar to char type </ENTRY>
<ENTRY> char(varchar 'varchar string') </ENTRY>
<ENTRY> char(varchar) </ENTRY>
<ENTRY> char </ENTRY>
<ENTRY> convert varchar to char type </ENTRY>
<ENTRY> char(varchar 'varchar string') </ENTRY>
</ROW>
<ROW>
<ENTRY> initcap(text) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> first letter of each word to upper case </ENTRY>
<ENTRY> initcap('thomas') </ENTRY>
<ENTRY> initcap(text) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> first letter of each word to upper case </ENTRY>
<ENTRY> initcap('thomas') </ENTRY>
</ROW>
<ROW>
<ENTRY> lpad(text,int,text) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> left pad string to specified length </ENTRY>
<ENTRY> lpad('hi',4,'??') </ENTRY>
<ENTRY> lpad(text,int,text) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> left pad string to specified length </ENTRY>
<ENTRY> lpad('hi',4,'??') </ENTRY>
</ROW>
<ROW>
<ENTRY> ltrim(text,text) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> left trim characters from text </ENTRY>
<ENTRY> ltrim('xxxxtrim','x') </ENTRY>
<ENTRY> ltrim(text,text) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> left trim characters from text </ENTRY>
<ENTRY> ltrim('xxxxtrim','x') </ENTRY>
</ROW>
<ROW>
<ENTRY> textpos(text,text) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> locate specified substring </ENTRY>
<ENTRY> position('high','ig') </ENTRY>
<ENTRY> textpos(text,text) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> locate specified substring </ENTRY>
<ENTRY> position('high','ig') </ENTRY>
</ROW>
<ROW>
<ENTRY> rpad(text,int,text) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> right pad string to specified length </ENTRY>
<ENTRY> rpad('hi',4,'x') </ENTRY>
<ENTRY> rpad(text,int,text) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> right pad string to specified length </ENTRY>
<ENTRY> rpad('hi',4,'x') </ENTRY>
</ROW>
<ROW>
<ENTRY> rtrim(text,text) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> right trim characters from text </ENTRY>
<ENTRY> rtrim('trimxxxx','x') </ENTRY>
<ENTRY> rtrim(text,text) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> right trim characters from text </ENTRY>
<ENTRY> rtrim('trimxxxx','x') </ENTRY>
</ROW>
<ROW>
<ENTRY> substr(text,int[,int]) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> extract specified substring </ENTRY>
<ENTRY> substr('hi there',3,5) </ENTRY>
<ENTRY> substr(text,int[,int]) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> extract specified substring </ENTRY>
<ENTRY> substr('hi there',3,5) </ENTRY>
</ROW>
<ROW>
<ENTRY> text(char) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> convert char to text type </ENTRY>
<ENTRY> text('char string') </ENTRY>
<ENTRY> text(char) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> convert char to text type </ENTRY>
<ENTRY> text('char string') </ENTRY>
</ROW>
<ROW>
<ENTRY> text(varchar) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> convert varchar to text type </ENTRY>
<ENTRY> text(varchar 'varchar string') </ENTRY>
<ENTRY> text(varchar) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> convert varchar to text type </ENTRY>
<ENTRY> text(varchar 'varchar string') </ENTRY>
</ROW>
<ROW>
<ENTRY> translate(text,from,to) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> convert character in string </ENTRY>
<ENTRY> translate('12345', '1', 'a') </ENTRY>
<ENTRY> translate(text,from,to) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> convert character in string </ENTRY>
<ENTRY> translate('12345', '1', 'a') </ENTRY>
</ROW>
<ROW>
<ENTRY> varchar(char) </ENTRY>
<ENTRY> varchar </ENTRY>
<ENTRY> convert char to varchar type </ENTRY>
<ENTRY> varchar('char string') </ENTRY>
<ENTRY> varchar(char) </ENTRY>
<ENTRY> varchar </ENTRY>
<ENTRY> convert char to varchar type </ENTRY>
<ENTRY> varchar('char string') </ENTRY>
</ROW>
<ROW>
<ENTRY> varchar(text) </ENTRY>
<ENTRY> varchar </ENTRY>
<ENTRY> convert text to varchar type </ENTRY>
<ENTRY> varchar('text string') </ENTRY>
<ENTRY> varchar(text) </ENTRY>
<ENTRY> varchar </ENTRY>
<ENTRY> convert text to varchar type </ENTRY>
<ENTRY> varchar('text string') </ENTRY>
</ROW>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</TBODY>
</TGROUP>
</TABLE>
</Para>
<para>
Most functions explicitly defined for text will work for char() and varchar() arguments.
</para>
</sect1>
<para>
Most functions explicitly defined for text will work for char() and varchar() arguments.
</para>
</sect1>
<sect1>
<title>Date/Time Functions</title>
<sect1>
<title>Date/Time Functions</title>
<para>
The date/time functions provide a powerful set of tools for manipulating various date/time types.
</para>
<para>
The date/time functions provide a powerful set of tools
for manipulating various date/time types.
</para>
<Para>
<TABLE TOCENTRY="1">
<TITLE>Date/Time Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<Para>
<TABLE TOCENTRY="1">
<TITLE>Date/Time Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<ROW>
<ENTRY>Function</ENTRY>
<ENTRY>Returns</ENTRY>
<ENTRY>Description</ENTRY>
<ENTRY>Example</ENTRY>
</ROW>
</THEAD>
<TBODY>
</THEAD>
<TBODY>
<ROW>
<ENTRY> abstime(datetime) </ENTRY>
<ENTRY> abstime </ENTRY>
<ENTRY> convert to abstime </ENTRY>
<ENTRY> abstime('now'::datetime) </ENTRY>
<ENTRY> abstime(datetime) </ENTRY>
<ENTRY> abstime </ENTRY>
<ENTRY> convert to abstime </ENTRY>
<ENTRY> abstime('now'::datetime) </ENTRY>
</ROW>
<ROW>
<ENTRY> age(datetime,datetime) </ENTRY>
<ENTRY> timespan </ENTRY>
<ENTRY> span preserving months and years </ENTRY>
<ENTRY> age('now','1957-06-13'::datetime) </ENTRY>
<ENTRY> age(datetime,datetime) </ENTRY>
<ENTRY> timespan </ENTRY>
<ENTRY> span preserving months and years </ENTRY>
<ENTRY> age('now','1957-06-13'::datetime) </ENTRY>
</ROW>
<ROW>
<ENTRY> datetime(abstime) </ENTRY>
<ENTRY> datetime </ENTRY>
<ENTRY> convert to datetime </ENTRY>
<ENTRY> datetime('now'::abstime) </ENTRY>
<ENTRY> datetime(abstime) </ENTRY>
<ENTRY> datetime </ENTRY>
<ENTRY> convert to datetime </ENTRY>
<ENTRY> datetime('now'::abstime) </ENTRY>
</ROW>
<ROW>
<ENTRY> datetime(date) </ENTRY>
<ENTRY> datetime </ENTRY>
<ENTRY> convert to datetime </ENTRY>
<ENTRY> datetime('today'::date) </ENTRY>
<ENTRY> datetime(date) </ENTRY>
<ENTRY> datetime </ENTRY>
<ENTRY> convert to datetime </ENTRY>
<ENTRY> datetime('today'::date) </ENTRY>
</ROW>
<ROW>
<ENTRY> datetime(date,time) </ENTRY>
<ENTRY> datetime </ENTRY>
<ENTRY> convert to datetime </ENTRY>
<ENTRY> datetime('1998-02-24'::datetime, '23:07'::time); </ENTRY>
<ENTRY> datetime(date,time) </ENTRY>
<ENTRY> datetime </ENTRY>
<ENTRY> convert to datetime </ENTRY>
<ENTRY> datetime('1998-02-24'::datetime, '23:07'::time); </ENTRY>
</ROW>
<ROW>
<ENTRY> date_part(text,datetime) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> specified portion of date field </ENTRY>
<ENTRY> date_part('dow','now'::datetime) </ENTRY>
<ENTRY> date_part(text,datetime) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> specified portion of date field </ENTRY>
<ENTRY> date_part('dow','now'::datetime) </ENTRY>
</ROW>
<ROW>
<ENTRY> date_part(text,timespan) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> specified portion of time field </ENTRY>
<ENTRY> date_part('hour','4 hrs 3 mins'::timespan) </ENTRY>
<ENTRY> date_part(text,timespan) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> specified portion of time field </ENTRY>
<ENTRY> date_part('hour','4 hrs 3 mins'::timespan) </ENTRY>
</ROW>
<ROW>
<ENTRY> date_trunc(text,datetime) </ENTRY>
<ENTRY> datetime </ENTRY>
<ENTRY> truncate date at specified units </ENTRY>
<ENTRY> date_trunc('month','now'::abstime) </ENTRY>
<ENTRY> date_trunc(text,datetime) </ENTRY>
<ENTRY> datetime </ENTRY>
<ENTRY> truncate date at specified units </ENTRY>
<ENTRY> date_trunc('month','now'::abstime) </ENTRY>
</ROW>
<ROW>
<ENTRY> isfinite(abstime) </ENTRY>
<ENTRY> bool </ENTRY>
<ENTRY> TRUE if this is a finite time </ENTRY>
<ENTRY> isfinite('now'::abstime) </ENTRY>
<ENTRY> isfinite(abstime) </ENTRY>
<ENTRY> bool </ENTRY>
<ENTRY> TRUE if this is a finite time </ENTRY>
<ENTRY> isfinite('now'::abstime) </ENTRY>
</ROW>
<ROW>
<ENTRY> isfinite(datetime) </ENTRY>
<ENTRY> bool </ENTRY>
<ENTRY> TRUE if this is a finite time </ENTRY>
<ENTRY> isfinite('now'::datetime) </ENTRY>
<ENTRY> isfinite(datetime) </ENTRY>
<ENTRY> bool </ENTRY>
<ENTRY> TRUE if this is a finite time </ENTRY>
<ENTRY> isfinite('now'::datetime) </ENTRY>
</ROW>
<ROW>
<ENTRY> isfinite(timespan) </ENTRY>
<ENTRY> bool </ENTRY>
<ENTRY> TRUE if this is a finite time </ENTRY>
<ENTRY> isfinite('4 hrs'::timespan) </ENTRY>
<ENTRY> isfinite(timespan) </ENTRY>
<ENTRY> bool </ENTRY>
<ENTRY> TRUE if this is a finite time </ENTRY>
<ENTRY> isfinite('4 hrs'::timespan) </ENTRY>
</ROW>
<ROW>
<ENTRY> reltime(timespan) </ENTRY>
<ENTRY> reltime </ENTRY>
<ENTRY> convert to reltime </ENTRY>
<ENTRY> reltime('4 hrs'::timespan) </ENTRY>
<ENTRY> reltime(timespan) </ENTRY>
<ENTRY> reltime </ENTRY>
<ENTRY> convert to reltime </ENTRY>
<ENTRY> reltime('4 hrs'::timespan) </ENTRY>
</ROW>
<ROW>
<ENTRY> timespan(reltime) </ENTRY>
<ENTRY> timespan </ENTRY>
<ENTRY> convert to timespan </ENTRY>
<ENTRY> timespan('4 hours'::reltime) </ENTRY>
<ENTRY> timespan(reltime) </ENTRY>
<ENTRY> timespan </ENTRY>
<ENTRY> convert to timespan </ENTRY>
<ENTRY> timespan('4 hours'::reltime) </ENTRY>
</ROW>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</TBODY>
</TGROUP>
</TABLE>
</Para>
<Para>
For the
<Function>date_part</Function> and <Function>date_trunc</Function>
functions, arguments can be
`year', `month', `day', `hour', `minute', and `second',
as well as the more specialized quantities
`decade', `century', `millenium', `millisecond', and `microsecond'.
<Function>date_part</Function> allows `dow'
to return day of week and `epoch' to return seconds since 1970 (for <Type>datetime</Type>)
or 'epoch' to return total elapsed seconds (for <Type>timespan</Type>).
</Para>
</sect1>
<Para>
For the
<Function>date_part</Function> and <Function>date_trunc</Function>
functions, arguments can be
`year', `month', `day', `hour', `minute', and `second',
as well as the more specialized quantities
`decade', `century', `millenium', `millisecond', and `microsecond'.
<Function>date_part</Function> allows `dow'
to return day of week and `epoch' to return seconds since 1970 (for <Type>datetime</Type>)
or 'epoch' to return total elapsed seconds (for <Type>timespan</Type>).
</Para>
</sect1>
<sect1>
<title>Geometric Functions</title>
<sect1>
<title>Geometric Functions</title>
<para>
The geometric types point, box, lseg, line, path, polygon, and circle have a large set of native
support functions.
</para>
<para>
The geometric types point, box, lseg, line, path, polygon, and
circle have a large set of native support functions.
</para>
<Para>
<TABLE TOCENTRY="1">
<TITLE>Geometric Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<Para>
<TABLE TOCENTRY="1">
<TITLE>Geometric Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<ROW>
<ENTRY>Function</ENTRY>
<ENTRY>Returns</ENTRY>
<ENTRY>Description</ENTRY>
<ENTRY>Example</ENTRY>
</ROW>
</THEAD>
<TBODY>
</THEAD>
<TBODY>
<ROW>
<ENTRY> area(box) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> area of box </ENTRY>
<ENTRY> area('((0,0),(1,1))'::box) </ENTRY>
<ENTRY> area(box) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> area of box </ENTRY>
<ENTRY> area('((0,0),(1,1))'::box) </ENTRY>
</ROW>
<ROW>
<ENTRY> area(circle) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> area of circle </ENTRY>
<ENTRY> area('((0,0),2.0)'::circle) </ENTRY>
<ENTRY> area(circle) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> area of circle </ENTRY>
<ENTRY> area('((0,0),2.0)'::circle) </ENTRY>
</ROW>
<ROW>
<ENTRY> box(box,box) </ENTRY>
<ENTRY> box </ENTRY>
<ENTRY> boxes to intersection box </ENTRY>
<ENTRY> box('((0,0),(1,1))','((0.5,0.5),(2,2))') </ENTRY>
<ENTRY> box(box,box) </ENTRY>
<ENTRY> box </ENTRY>
<ENTRY> boxes to intersection box </ENTRY>
<ENTRY> box('((0,0),(1,1))','((0.5,0.5),(2,2))') </ENTRY>
</ROW>
<ROW>
<ENTRY> center(box) </ENTRY>
<ENTRY> point </ENTRY>
<ENTRY> center of object </ENTRY>
<ENTRY> center('((0,0),(1,2))'::box) </ENTRY>
<ENTRY> center(box) </ENTRY>
<ENTRY> point </ENTRY>
<ENTRY> center of object </ENTRY>
<ENTRY> center('((0,0),(1,2))'::box) </ENTRY>
</ROW>
<ROW>
<ENTRY> center(circle) </ENTRY>
<ENTRY> point </ENTRY>
<ENTRY> center of object </ENTRY>
<ENTRY> center('((0,0),2.0)'::circle) </ENTRY>
<ENTRY> center(circle) </ENTRY>
<ENTRY> point </ENTRY>
<ENTRY> center of object </ENTRY>
<ENTRY> center('((0,0),2.0)'::circle) </ENTRY>
</ROW>
<ROW>
<ENTRY> diameter(circle) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> diameter of circle </ENTRY>
<ENTRY> diameter('((0,0),2.0)'::circle) </ENTRY>
<ENTRY> diameter(circle) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> diameter of circle </ENTRY>
<ENTRY> diameter('((0,0),2.0)'::circle) </ENTRY>
</ROW>
<ROW>
<ENTRY> height(box) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> vertical size of box </ENTRY>
<ENTRY> height('((0,0),(1,1))'::box) </ENTRY>
<ENTRY> height(box) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> vertical size of box </ENTRY>
<ENTRY> height('((0,0),(1,1))'::box) </ENTRY>
</ROW>
<ROW>
<ENTRY> isclosed(path) </ENTRY>
<ENTRY> bool </ENTRY>
<ENTRY> TRUE if this is a closed path </ENTRY>
<ENTRY> isclosed('((0,0),(1,1),(2,0))'::path) </ENTRY>
<ENTRY> isclosed(path) </ENTRY>
<ENTRY> bool </ENTRY>
<ENTRY> TRUE if this is a closed path </ENTRY>
<ENTRY> isclosed('((0,0),(1,1),(2,0))'::path) </ENTRY>
</ROW>
<ROW>
<ENTRY> isopen(path) </ENTRY>
<ENTRY> bool </ENTRY>
<ENTRY> TRUE if this is an open path </ENTRY>
<ENTRY> isopen('[(0,0),(1,1),(2,0)]'::path) </ENTRY>
<ENTRY> isopen(path) </ENTRY>
<ENTRY> bool </ENTRY>
<ENTRY> TRUE if this is an open path </ENTRY>
<ENTRY> isopen('[(0,0),(1,1),(2,0)]'::path) </ENTRY>
</ROW>
<ROW>
<ENTRY> length(lseg) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> length of line segment </ENTRY>
<ENTRY> length('((-1,0),(1,0))'::lseg) </ENTRY>
<ENTRY> length(lseg) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> length of line segment </ENTRY>
<ENTRY> length('((-1,0),(1,0))'::lseg) </ENTRY>
</ROW>
<ROW>
<ENTRY> length(path) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> length of path </ENTRY>
<ENTRY> length('((0,0),(1,1),(2,0))'::path) </ENTRY>
<ENTRY> length(path) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> length of path </ENTRY>
<ENTRY> length('((0,0),(1,1),(2,0))'::path) </ENTRY>
</ROW>
<ROW>
<ENTRY> pclose(path) </ENTRY>
<ENTRY> path </ENTRY>
<ENTRY> convert path to closed variant </ENTRY>
<ENTRY> popen('[(0,0),(1,1),(2,0)]'::path) </ENTRY>
<ENTRY> pclose(path) </ENTRY>
<ENTRY> path </ENTRY>
<ENTRY> convert path to closed variant </ENTRY>
<ENTRY> popen('[(0,0),(1,1),(2,0)]'::path) </ENTRY>
</ROW>
<ROW>
<ENTRY> point(lseg,lseg) </ENTRY>
<ENTRY> point </ENTRY>
<ENTRY> convert to point (intersection) </ENTRY>
<ENTRY> point('((-1,0),(1,0))'::lseg,'((-2,-2),(2,2))'::lseg) </ENTRY>
<ENTRY> point(lseg,lseg) </ENTRY>
<ENTRY> point </ENTRY>
<ENTRY> convert to point (intersection) </ENTRY>
<ENTRY> point('((-1,0),(1,0))'::lseg,'((-2,-2),(2,2))'::lseg) </ENTRY>
</ROW>
<ROW>
<ENTRY> points(path) </ENTRY>
<ENTRY> int4 </ENTRY>
<ENTRY> number of points in path </ENTRY>
<ENTRY> points('[(0,0),(1,1),(2,0)]'::path) </ENTRY>
<ENTRY> points(path) </ENTRY>
<ENTRY> int4 </ENTRY>
<ENTRY> number of points in path </ENTRY>
<ENTRY> points('[(0,0),(1,1),(2,0)]'::path) </ENTRY>
</ROW>
<ROW>
<ENTRY> popen(path) </ENTRY>
<ENTRY> path </ENTRY>
<ENTRY> convert path to open variant </ENTRY>
<ENTRY> popen('((0,0),(1,1),(2,0))'::path) </ENTRY>
<ENTRY> popen(path) </ENTRY>
<ENTRY> path </ENTRY>
<ENTRY> convert path to open variant </ENTRY>
<ENTRY> popen('((0,0),(1,1),(2,0))'::path) </ENTRY>
</ROW>
<ROW>
<ENTRY> radius(circle) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> radius of circle </ENTRY>
<ENTRY> radius('((0,0),2.0)'::circle) </ENTRY>
<ENTRY> radius(circle) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> radius of circle </ENTRY>
<ENTRY> radius('((0,0),2.0)'::circle) </ENTRY>
</ROW>
<ROW>
<ENTRY> width(box) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> horizontal size of box </ENTRY>
<ENTRY> width('((0,0),(1,1))'::box) </ENTRY>
<ENTRY> width(box) </ENTRY>
<ENTRY> float8 </ENTRY>
<ENTRY> horizontal size of box </ENTRY>
<ENTRY> width('((0,0),(1,1))'::box) </ENTRY>
</ROW>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</TBODY>
</TGROUP>
</TABLE>
</Para>
<Para>
<TABLE TOCENTRY="1">
<TITLE>Geometric Type Conversion Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<Para>
<TABLE TOCENTRY="1">
<TITLE>Geometric Type Conversion Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<ROW>
<ENTRY>Function</ENTRY>
<ENTRY>Returns</ENTRY>
<ENTRY>Description</ENTRY>
<ENTRY>Example</ENTRY>
</ROW>
</THEAD>
<TBODY>
</THEAD>
<TBODY>
<ROW>
<ENTRY> box(circle) </ENTRY>
<ENTRY> box </ENTRY>
<ENTRY> convert circle to box </ENTRY>
<ENTRY> box('((0,0),2.0)'::circle) </ENTRY>
<ENTRY> box(circle) </ENTRY>
<ENTRY> box </ENTRY>
<ENTRY> convert circle to box </ENTRY>
<ENTRY> box('((0,0),2.0)'::circle) </ENTRY>
</ROW>
<ROW>
<ENTRY> box(point,point) </ENTRY>
<ENTRY> box </ENTRY>
<ENTRY> convert points to box </ENTRY>
<ENTRY> box('(0,0)'::point,'(1,1)'::point) </ENTRY>
<ENTRY> box(point,point) </ENTRY>
<ENTRY> box </ENTRY>
<ENTRY> convert points to box </ENTRY>
<ENTRY> box('(0,0)'::point,'(1,1)'::point) </ENTRY>
</ROW>
<ROW>
<ENTRY> box(polygon) </ENTRY>
<ENTRY> box </ENTRY>
<ENTRY> convert polygon to box </ENTRY>
<ENTRY> box('((0,0),(1,1),(2,0))'::polygon) </ENTRY>
<ENTRY> box(polygon) </ENTRY>
<ENTRY> box </ENTRY>
<ENTRY> convert polygon to box </ENTRY>
<ENTRY> box('((0,0),(1,1),(2,0))'::polygon) </ENTRY>
</ROW>
<ROW>
<ENTRY> circle(box) </ENTRY>
<ENTRY> circle </ENTRY>
<ENTRY> convert to circle </ENTRY>
<ENTRY> circle('((0,0),(1,1))'::box) </ENTRY>
<ENTRY> circle(box) </ENTRY>
<ENTRY> circle </ENTRY>
<ENTRY> convert to circle </ENTRY>
<ENTRY> circle('((0,0),(1,1))'::box) </ENTRY>
</ROW>
<ROW>
<ENTRY> circle(point,float8) </ENTRY>
<ENTRY> circle </ENTRY>
<ENTRY> convert to circle </ENTRY>
<ENTRY> circle('(0,0)'::point,2.0) </ENTRY>
<ENTRY> circle(point,float8) </ENTRY>
<ENTRY> circle </ENTRY>
<ENTRY> convert to circle </ENTRY>
<ENTRY> circle('(0,0)'::point,2.0) </ENTRY>
</ROW>
<ROW>
<ENTRY> lseg(box) </ENTRY>
<ENTRY> lseg </ENTRY>
<ENTRY> convert diagonal to lseg </ENTRY>
<ENTRY> lseg('((-1,0),(1,0))'::box) </ENTRY>
<ENTRY> lseg(box) </ENTRY>
<ENTRY> lseg </ENTRY>
<ENTRY> convert diagonal to lseg </ENTRY>
<ENTRY> lseg('((-1,0),(1,0))'::box) </ENTRY>
</ROW>
<ROW>
<ENTRY> lseg(point,point) </ENTRY>
<ENTRY> lseg </ENTRY>
<ENTRY> convert to lseg </ENTRY>
<ENTRY> lseg('(-1,0)'::point,'(1,0)'::point) </ENTRY>
<ENTRY> lseg(point,point) </ENTRY>
<ENTRY> lseg </ENTRY>
<ENTRY> convert to lseg </ENTRY>
<ENTRY> lseg('(-1,0)'::point,'(1,0)'::point) </ENTRY>
</ROW>
<ROW>
<ENTRY> path(polygon) </ENTRY>
<ENTRY> point </ENTRY>
<ENTRY> convert to path </ENTRY>
<ENTRY> path('((0,0),(1,1),(2,0))'::polygon) </ENTRY>
<ENTRY> path(polygon) </ENTRY>
<ENTRY> point </ENTRY>
<ENTRY> convert to path </ENTRY>
<ENTRY> path('((0,0),(1,1),(2,0))'::polygon) </ENTRY>
</ROW>
<ROW>
<ENTRY> point(circle) </ENTRY>
<ENTRY> point </ENTRY>
<ENTRY> convert to point (center) </ENTRY>
<ENTRY> point('((0,0),2.0)'::circle) </ENTRY>
<ENTRY> point(circle) </ENTRY>
<ENTRY> point </ENTRY>
<ENTRY> convert to point (center) </ENTRY>
<ENTRY> point('((0,0),2.0)'::circle) </ENTRY>
</ROW>
<ROW>
<ENTRY> point(lseg,lseg) </ENTRY>
<ENTRY> point </ENTRY>
<ENTRY> convert to point (intersection) </ENTRY>
<ENTRY> point('((-1,0),(1,0))'::lseg,'((-2,-2),(2,2))'::lseg) </ENTRY>
<ENTRY> point(lseg,lseg) </ENTRY>
<ENTRY> point </ENTRY>
<ENTRY> convert to point (intersection) </ENTRY>
<ENTRY> point('((-1,0),(1,0))'::lseg,'((-2,-2),(2,2))'::lseg) </ENTRY>
</ROW>
<ROW>
<ENTRY> point(polygon) </ENTRY>
<ENTRY> point </ENTRY>
<ENTRY> center of polygon </ENTRY>
<ENTRY> point('((0,0),(1,1),(2,0))'::polygon) </ENTRY>
<ENTRY> point(polygon) </ENTRY>
<ENTRY> point </ENTRY>
<ENTRY> center of polygon </ENTRY>
<ENTRY> point('((0,0),(1,1),(2,0))'::polygon) </ENTRY>
</ROW>
<ROW>
<ENTRY> polygon(box) </ENTRY>
<ENTRY> polygon </ENTRY>
<ENTRY> convert to polygon with 12 points </ENTRY>
<ENTRY> polygon('((0,0),(1,1))'::box) </ENTRY>
<ENTRY> polygon(box) </ENTRY>
<ENTRY> polygon </ENTRY>
<ENTRY> convert to polygon with 12 points </ENTRY>
<ENTRY> polygon('((0,0),(1,1))'::box) </ENTRY>
</ROW>
<ROW>
<ENTRY> polygon(circle) </ENTRY>
<ENTRY> polygon </ENTRY>
<ENTRY> convert to polygon with 12 points </ENTRY>
<ENTRY> polygon('((0,0),2.0)'::circle) </ENTRY>
<ENTRY> polygon(circle) </ENTRY>
<ENTRY> polygon </ENTRY>
<ENTRY> convert to polygon with 12 points </ENTRY>
<ENTRY> polygon('((0,0),2.0)'::circle) </ENTRY>
</ROW>
<ROW>
<ENTRY> polygon(npts,circle) </ENTRY>
<ENTRY> polygon </ENTRY>
<ENTRY> convert to polygon with npts points </ENTRY>
<ENTRY> polygon(12,'((0,0),2.0)'::circle) </ENTRY>
<ENTRY> polygon(npts,circle) </ENTRY>
<ENTRY> polygon </ENTRY>
<ENTRY> convert to polygon with npts points </ENTRY>
<ENTRY> polygon(12,'((0,0),2.0)'::circle) </ENTRY>
</ROW>
<ROW>
<ENTRY> polygon(path) </ENTRY>
<ENTRY> polygon </ENTRY>
<ENTRY> convert to polygon </ENTRY>
<ENTRY> polygon('((0,0),(1,1),(2,0))'::path) </ENTRY>
<ENTRY> polygon(path) </ENTRY>
<ENTRY> polygon </ENTRY>
<ENTRY> convert to polygon </ENTRY>
<ENTRY> polygon('((0,0),(1,1),(2,0))'::path) </ENTRY>
</ROW>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</TBODY>
</TGROUP>
</TABLE>
</Para>
<Para>
<TABLE TOCENTRY="1">
<TITLE>Geometric Upgrade Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<Para>
<TABLE TOCENTRY="1">
<TITLE>Geometric Upgrade Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<ROW>
<ENTRY>Function</ENTRY>
<ENTRY>Returns</ENTRY>
<ENTRY>Description</ENTRY>
<ENTRY>Example</ENTRY>
</ROW>
</THEAD>
<TBODY>
</THEAD>
<TBODY>
<ROW>
<ENTRY> isoldpath(path) </ENTRY>
<ENTRY> path </ENTRY>
<ENTRY> test path for pre-v6.1 form </ENTRY>
<ENTRY> isoldpath('(1,3,0,0,1,1,2,0)'::path) </ENTRY>
<ENTRY> isoldpath(path) </ENTRY>
<ENTRY> path </ENTRY>
<ENTRY> test path for pre-v6.1 form </ENTRY>
<ENTRY> isoldpath('(1,3,0,0,1,1,2,0)'::path) </ENTRY>
</ROW>
<ROW>
<ENTRY> revertpoly(polygon) </ENTRY>
<ENTRY> polygon </ENTRY>
<ENTRY> convert pre-v6.1 polygon </ENTRY>
<ENTRY> revertpoly('((0,0),(1,1),(2,0))'::polygon) </ENTRY>
<ENTRY> revertpoly(polygon) </ENTRY>
<ENTRY> polygon </ENTRY>
<ENTRY> convert pre-v6.1 polygon </ENTRY>
<ENTRY> revertpoly('((0,0),(1,1),(2,0))'::polygon) </ENTRY>
</ROW>
<ROW>
<ENTRY> upgradepath(path) </ENTRY>
<ENTRY> path </ENTRY>
<ENTRY> convert pre-v6.1 path </ENTRY>
<ENTRY> upgradepath('(1,3,0,0,1,1,2,0)'::path) </ENTRY>
<ENTRY> upgradepath(path) </ENTRY>
<ENTRY> path </ENTRY>
<ENTRY> convert pre-v6.1 path </ENTRY>
<ENTRY> upgradepath('(1,3,0,0,1,1,2,0)'::path) </ENTRY>
</ROW>
<ROW>
<ENTRY> upgradepoly(polygon) </ENTRY>
<ENTRY> polygon </ENTRY>
<ENTRY> convert pre-v6.1 polygon </ENTRY>
<ENTRY> upgradepoly('(0,1,2,0,1,0)'::polygon) </ENTRY>
<ENTRY> upgradepoly(polygon) </ENTRY>
<ENTRY> polygon </ENTRY>
<ENTRY> convert pre-v6.1 polygon </ENTRY>
<ENTRY> upgradepoly('(0,1,2,0,1,0)'::polygon) </ENTRY>
</ROW>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</sect1>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</sect1>
<sect1>
<title id="cidr-funcs">IP V4 Functions</title>
<sect1>
<title id="cidr-funcs">IP V4 Functions</title>
<Para>
<TABLE TOCENTRY="1">
<TITLE><ProductName>Postgres</ProductName>IP V4 Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<Para>
<TABLE TOCENTRY="1">
<TITLE><ProductName>Postgres</ProductName>IP V4 Functions</TITLE>
<TGROUP COLS="4">
<THEAD>
<ROW>
<ENTRY>Function</ENTRY>
<ENTRY>Returns</ENTRY>
<ENTRY>Description</ENTRY>
<ENTRY>Example</ENTRY>
</ROW>
</THEAD>
<TBODY>
</THEAD>
<TBODY>
<ROW>
<ENTRY> broadcast(cidr) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> construct broadcast address as text </ENTRY>
<ENTRY> broadcast('192.168.1.5/24') ==> '192.168.1.255' </ENTRY>
<ENTRY> broadcast(cidr) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> construct broadcast address as text </ENTRY>
<ENTRY> broadcast('192.168.1.5/24') ==> '192.168.1.255' </ENTRY>
</ROW>
<ROW>
<ENTRY> broadcast(inet) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> construct broadcast address as text </ENTRY>
<ENTRY> broadcast('192.168.1.5/24') ==> '192.168.1.255' </ENTRY>
<ENTRY> broadcast(inet) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> construct broadcast address as text </ENTRY>
<ENTRY> broadcast('192.168.1.5/24') ==> '192.168.1.255' </ENTRY>
</ROW>
<ROW>
<ENTRY> host(inet) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> extract host address as text </ENTRY>
<ENTRY> host('192.168.1.5/24') ==> '192.168.1.5' </ENTRY>
<ENTRY> host(inet) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> extract host address as text </ENTRY>
<ENTRY> host('192.168.1.5/24') ==> '192.168.1.5' </ENTRY>
</ROW>
<ROW>
<ENTRY> masklen(cidr) </ENTRY>
<ENTRY> int4 </ENTRY>
<ENTRY> calculate netmask length </ENTRY>
<ENTRY> masklen('192.168.1.5/24') ==> 24</ENTRY>
<ENTRY> masklen(cidr) </ENTRY>
<ENTRY> int4 </ENTRY>
<ENTRY> calculate netmask length </ENTRY>
<ENTRY> masklen('192.168.1.5/24') ==> 24</ENTRY>
</ROW>
<ROW>
<ENTRY> masklen(inet) </ENTRY>
<ENTRY> int4 </ENTRY>
<ENTRY> calculate netmask length </ENTRY>
<ENTRY> masklen('192.168.1.5/24') ==> 24 </ENTRY>
<ENTRY> masklen(inet) </ENTRY>
<ENTRY> int4 </ENTRY>
<ENTRY> calculate netmask length </ENTRY>
<ENTRY> masklen('192.168.1.5/24') ==> 24 </ENTRY>
</ROW>
<ROW>
<ENTRY> netmask(inet) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> construct netmask as text </ENTRY>
<ENTRY> netmask('192.168.1.5/24') ==> '255.255.255.0' </ENTRY>
<ENTRY> netmask(inet) </ENTRY>
<ENTRY> text </ENTRY>
<ENTRY> construct netmask as text </ENTRY>
<ENTRY> netmask('192.168.1.5/24') ==> '255.255.255.0' </ENTRY>
</ROW>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</Sect1>
</Sect1>
</chapter>
</chapter>
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......
doc/src/sgml/oper.sgml
View file @ 95e3cec6
<Chapter Id="operators">
<Title>Operators</Title>
<Chapter Id="operators">
<Title id="operators-title">Operators</Title>
<Abstract>
<Para>
Describes the built-in operators available in
<ProductName>Postgres</ProductName>.
</Para>
</Abstract>
<Abstract>
<Para>
Describes the built-in operators available in
<ProductName>Postgres</ProductName>.
</Para>
</Abstract>
<Para>
<ProductName>Postgres</ProductName> provides a large number of
built-in operators on system types.
These operators are declared in the system catalog
pg_operator. Every entry in pg_operator includes
the name of the procedure that implements the operator and the
class <Acronym>OIDs</Acronym> of the input and output types.
</Para>
<Para>
<ProductName>Postgres</ProductName> provides a large number of
built-in operators on system types.
These operators are declared in the system catalog
pg_operator. Every entry in pg_operator includes
the name of the procedure that implements the operator and the
class <Acronym>OIDs</Acronym> of the input and output types.
</Para>
<Para>
To view all variations of the <Quote>||</Quote> string concatenation operator,
try
<ProgramListing>
<Para>
To view all variations of the <Quote>||</Quote> string concatenation operator,
try
<ProgramListing>
SELECT oprleft, oprright, oprresult, oprcode
FROM pg_operator WHERE oprname = '||';
......@@ -30,37 +30,37 @@ oprleft|oprright|oprresult|oprcode
1042| 1042| 1042|textcat
1043| 1043| 1043|textcat
(3 rows)
</ProgramListing>
</Para>
</ProgramListing>
</Para>
<Para>
Users may invoke operators using the operator name, as in:
<Para>
Users may invoke operators using the operator name, as in:
<ProgramListing>
<ProgramListing>
select * from emp where salary < 40000;
</ProgramListing>
</ProgramListing>
Alternatively, users may call the functions that implement the
operators directly. In this case, the query above would be expressed
as:
<ProgramListing>
Alternatively, users may call the functions that implement the
operators directly. In this case, the query above would be expressed
as:
<ProgramListing>
select * from emp where int4lt(salary, 40000);
</ProgramListing>
</Para>
</ProgramListing>
</Para>
<Para>
<Application>psql</Application>
has a command (<Command>\dd</Command>) to show these operators.
</Para>
<Para>
<Application>psql</Application>
has a command (<Command>\dd</Command>) to show these operators.
</Para>
<sect1>
<title>Lexical Precedence</title>
<sect1>
<title>Lexical Precedence</title>
<para>
Operators have a precedence which is currently hardcoded into the parser.
Most operators have the same precedence and are left-associative. This may lead
to non-intuitive behavior; for example the boolean operators "&lt;" and "&gt;"
have a different precedence that the boolean operators "&lt;=" and "&gt;=".
<para>
Operators have a precedence which is currently hardcoded into the parser.
Most operators have the same precedence and are left-associative. This may lead
to non-intuitive behavior; for example the boolean operators "&lt;" and "&gt;"
have a different precedence that the boolean operators "&lt;=" and "&gt;=".
<table tocentry="1">
<title>
......@@ -322,26 +322,27 @@ logical union
</para>
</sect1>
<sect1>
<title>General Operators</title>
<sect1>
<title>General Operators</title>
<para>
The operators listed here are defined for a number of native data types,
ranging from numeric types to data/time types.
</para>
<Para>
<TABLE TOCENTRY="1">
<TITLE><ProductName>Postgres</ProductName> Operators</TITLE>
<TITLEABBREV>Operators</TITLEABBREV>
<TGROUP COLS="3">
<THEAD>
<para>
The operators listed here are defined for a number of native data types,
ranging from numeric types to data/time types.
</para>
<Para>
<TABLE TOCENTRY="1">
<TITLE><ProductName>Postgres</ProductName> Operators</TITLE>
<TITLEABBREV>Operators</TITLEABBREV>
<TGROUP COLS="3">
<THEAD>
<ROW>
<ENTRY>Operator</ENTRY>
<ENTRY>Description</ENTRY>
<ENTRY>Usage</ENTRY>
</ROW>
</THEAD>
<TBODY>
</THEAD>
<TBODY>
<ROW>
<ENTRY> &lt; </ENTRY>
<ENTRY>Less than?</ENTRY>
......@@ -412,28 +413,28 @@ ranging from numeric types to data/time types.
<ENTRY>Does not match (regex), case insensitive</ENTRY>
<ENTRY>'thomas' !~ '.*vadim.*'</ENTRY>
</ROW>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</sect1>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</sect1>
<sect1>
<title id="math-opers">Numerical Operators</title>
<sect1>
<title id="math-opers">Numerical Operators</title>
<Para>
<TABLE TOCENTRY="1">
<TITLE><ProductName>Postgres</ProductName> Numerical Operators</TITLE>
<TITLEABBREV>Operators</TITLEABBREV>
<TGROUP COLS="3">
<THEAD>
<Para>
<TABLE TOCENTRY="1">
<TITLE><ProductName>Postgres</ProductName> Numerical Operators</TITLE>
<TITLEABBREV>Operators</TITLEABBREV>
<TGROUP COLS="3">
<THEAD>
<ROW>
<ENTRY>Operator</ENTRY>
<ENTRY>Description</ENTRY>
<ENTRY>Usage</ENTRY>
</ROW>
</THEAD>
<TBODY>
</THEAD>
<TBODY>
<ROW>
<ENTRY> ! </ENTRY>
<ENTRY>Factorial</ENTRY>
......@@ -504,28 +505,28 @@ ranging from numeric types to data/time types.
<ENTRY>Cube root</ENTRY>
<ENTRY>||/ 27.0</ENTRY>
</ROW>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</sect1>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</sect1>
<sect1>
<title>Geometric Operators</title>
<sect1>
<title>Geometric Operators</title>
<Para>
<TABLE TOCENTRY="1">
<TITLE><ProductName>Postgres</ProductName> Geometric Operators</TITLE>
<TITLEABBREV>Operators</TITLEABBREV>
<TGROUP COLS="3">
<THEAD>
<Para>
<TABLE TOCENTRY="1">
<TITLE><ProductName>Postgres</ProductName> Geometric Operators</TITLE>
<TITLEABBREV>Operators</TITLEABBREV>
<TGROUP COLS="3">
<THEAD>
<ROW>
<ENTRY>Operator</ENTRY>
<ENTRY>Description</ENTRY>
<ENTRY>Usage</ENTRY>
</ROW>
</THEAD>
<TBODY>
</THEAD>
<TBODY>
<ROW>
<ENTRY> + </ENTRY>
<ENTRY>Translation</ENTRY>
......@@ -646,32 +647,32 @@ ranging from numeric types to data/time types.
<ENTRY>Same as</ENTRY>
<ENTRY>'((0,0),(1,1))'::polygon ~= '((1,1),(0,0))'::polygon</ENTRY>
</ROW>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</sect1>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</sect1>
<sect1>
<title>Time Interval Operators</title>
<sect1>
<title>Time Interval Operators</title>
<Para>
The time interval data type <Type>tinterval</Type> is a legacy from the original
date/time types and is not as well supported as the more modern types. There
are several operators for this type.
<Para>
The time interval data type <Type>tinterval</Type> is a legacy from the original
date/time types and is not as well supported as the more modern types. There
are several operators for this type.
<TABLE TOCENTRY="1">
<TITLE><ProductName>Postgres</ProductName> Time Interval Operators</TITLE>
<TITLEABBREV>Operators</TITLEABBREV>
<TGROUP COLS="3">
<THEAD>
<TABLE TOCENTRY="1">
<TITLE><ProductName>Postgres</ProductName> Time Interval Operators</TITLE>
<TITLEABBREV>Operators</TITLEABBREV>
<TGROUP COLS="3">
<THEAD>
<ROW>
<ENTRY>Operator</ENTRY>
<ENTRY>Description</ENTRY>
<ENTRY>Usage</ENTRY>
</ROW>
</THEAD>
<TBODY>
</THEAD>
<TBODY>
<ROW>
<ENTRY> #&lt; </ENTRY>
<ENTRY>Interval less than?</ENTRY>
......@@ -727,28 +728,28 @@ are several operators for this type.
<ENTRY>Time inside interval?</ENTRY>
<ENTRY></ENTRY>
</ROW>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</sect1>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</sect1>
<Sect1>
<title id="cidr-opers">IP V4 CIDR Operators</title>
<Sect1>
<title id="cidr-opers">IP V4 CIDR Operators</title>
<Para>
<TABLE TOCENTRY="1">
<TITLE><ProductName>Postgres</ProductName>IP V4 CIDR Operators</TITLE>
<TITLEABBREV>Operators</TITLEABBREV>
<TGROUP COLS="3">
<THEAD>
<Para>
<TABLE TOCENTRY="1">
<TITLE><ProductName>Postgres</ProductName>IP V4 CIDR Operators</TITLE>
<TITLEABBREV>Operators</TITLEABBREV>
<TGROUP COLS="3">
<THEAD>
<ROW>
<ENTRY>Operator</ENTRY>
<ENTRY>Description</ENTRY>
<ENTRY>Usage</ENTRY>
</ROW>
</THEAD>
<TBODY>
</THEAD>
<TBODY>
<ROW>
<ENTRY> &lt; </ENTRY>
<ENTRY>Less than</ENTRY>
......@@ -799,28 +800,28 @@ are several operators for this type.
<ENTRY>contains or equals</ENTRY>
<ENTRY>'192.168.1/24'::cidr &gt;&gt;= '192.168.1/24'::cidr</ENTRY>
</ROW>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</Sect1>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</Sect1>
<Sect1>
<title id="inet-opers">IP V4 INET Operators</title>
<Sect1>
<title id="inet-opers">IP V4 INET Operators</title>
<Para>
<TABLE TOCENTRY="1">
<TITLE><ProductName>Postgres</ProductName>IP V4 INET Operators</TITLE>
<TITLEABBREV>Operators</TITLEABBREV>
<TGROUP COLS="3">
<THEAD>
<Para>
<TABLE TOCENTRY="1">
<TITLE><ProductName>Postgres</ProductName>IP V4 INET Operators</TITLE>
<TITLEABBREV>Operators</TITLEABBREV>
<TGROUP COLS="3">
<THEAD>
<ROW>
<ENTRY>Operator</ENTRY>
<ENTRY>Description</ENTRY>
<ENTRY>Usage</ENTRY>
</ROW>
</THEAD>
<TBODY>
</THEAD>
<TBODY>
<ROW>
<ENTRY> &lt; </ENTRY>
<ENTRY>Less than</ENTRY>
......@@ -871,11 +872,27 @@ are several operators for this type.
<ENTRY>contains or equals</ENTRY>
<ENTRY>'192.168.1/24'::inet &gt;&gt;= '192.168.1/24'::inet</ENTRY>
</ROW>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</Sect1>
</TBODY>
</TGROUP>
</TABLE>
</Para>
</Sect1>
</Chapter>
</Chapter>
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doc/src/sgml/syntax.sgml
View file @ 95e3cec6
<chapter>
<title>SQL Syntax</title>
<sect1>
<title>Key Words</title>
<para>
<acronym>SQL92</acronym> defines <firstterm>key words</firstterm>
for the language
which have specific meaning. Some key words are
<firstterm>reserved</firstterm>, which indicates that they are
restricted to appear in only certain contexts. Other key words are
<firstterm>not restricted</firstterm>, which indicates that in certain
contexts they
have a specific meaning but are not otherwise constrained.
</para>
<para>
<productname>Postgres</productname> implements an extended subset of the
<acronym>SQL92</acronym> and <acronym>SQL3</acronym> languages. Some language
elements are not as restricted in this implementation as is
called for in the language standards, in part due
to the extensibility features of <productname>Postgres</productname>.
</para>
<para>
Information on <acronym>SQL92</acronym> and <acronym>SQL3</acronym> key words
is derived from <xref linkend="DATE97" endterm="DATE97">.
</para>
<sect2>
<title>Reserved Key Words</title>
<para>
<acronym>SQL92</acronym> and <acronym>SQL3</acronym> have
<firstterm>reserved key words</firstterm> which are not allowed
as identifiers and not allowed in any usage other than as fundamental
tokens in <acronym>SQL</acronym> statements.
<productname>Postgres</productname> has additional key words
which have similar restrictions. In particular, these key words
are not allowed as column or table names, though in some cases
they are allowed to be column labels (i.e. in AS clauses).
</para>
<tip>
<para>
Any string can be specified as an identifier if surrounded by
double quotes (<quote>like this!</quote>). Some care is required since
such an identifier will be case sensitive
and will retain embedded whitespace other special characters.</para>
</tip>
<para>
The following are <productname>Postgres</productname>
reserved words which are neither <acronym>SQL92</acronym>
nor <acronym>SQL3</acronym> reserved words. These are allowed
to be present as column labels, but not as identifiers:
<programlisting>
<chapter>
<title>SQL Syntax</title>
<abstract>
<para>
<acronym>SQL</acronym> manipulates sets of data. The language is
composed of various <firstterm>key words</firstterm>. Arithmetic
and procedural expressions are allowed. We will cover these topics
in this chapter; subsequent chapters will include details on data
types, functions, and operators.
</para>
</abstract>
<sect1>
<title>Key Words</title>
<para>
<acronym>SQL92</acronym> defines <firstterm>key words</firstterm>
for the language
which have specific meaning. Some key words are
<firstterm>reserved</firstterm>, which indicates that they are
restricted to appear in only certain contexts. Other key words are
<firstterm>not restricted</firstterm>, which indicates that in certain
contexts they
have a specific meaning but are not otherwise constrained.
</para>
<para>
<productname>Postgres</productname> implements an extended subset of the
<acronym>SQL92</acronym> and <acronym>SQL3</acronym> languages. Some language
elements are not as restricted in this implementation as is
called for in the language standards, in part due
to the extensibility features of <productname>Postgres</productname>.
</para>
<para>
Information on <acronym>SQL92</acronym> and <acronym>SQL3</acronym> key words
is derived from <xref linkend="DATE97" endterm="DATE97">.
</para>
<sect2>
<title>Reserved Key Words</title>
<para>
<acronym>SQL92</acronym> and <acronym>SQL3</acronym> have
<firstterm>reserved key words</firstterm> which are not allowed
as identifiers and not allowed in any usage other than as fundamental
tokens in <acronym>SQL</acronym> statements.
<productname>Postgres</productname> has additional key words
which have similar restrictions. In particular, these key words
are not allowed as column or table names, though in some cases
they are allowed to be column labels (i.e. in AS clauses).
</para>
<tip>
<para>
Any string can be specified as an identifier if surrounded by
double quotes (<quote>like this!</quote>). Some care is required since
such an identifier will be case sensitive
and will retain embedded whitespace other special characters.
</para>
</tip>
<para>
The following are <productname>Postgres</productname>
reserved words which are neither <acronym>SQL92</acronym>
nor <acronym>SQL3</acronym> reserved words. These are allowed
to be present as column labels, but not as identifiers:
<programlisting>
ABORT ANALYZE
BINARY
CLUSTER CONSTRAINT COPY
......@@ -69,32 +80,33 @@ RESET
SETOF SHOW
UNLISTEN UNTIL
VACUUM VERBOSE
</programlisting>
</para>
</programlisting>
</para>
<para>
The following are <productname>Postgres</productname>
reserved words which are also <acronym>SQL92</acronym>
or <acronym>SQL3</acronym> reserved words, and which
are allowed to be present as column labels, but not as identifiers:
<para>
The following are <productname>Postgres</productname>
reserved words which are also <acronym>SQL92</acronym>
or <acronym>SQL3</acronym> reserved words, and which
are allowed to be present as column labels, but not as identifiers:
<programlisting>
<programlisting>
CASE COALESCE CROSS CURRENT
ELSE END
FALSE FOREIGN
GROUP
GLOBAL GROUP
LOCAL
NULLIF
ORDER
POSITION PRECISION
TABLE THEN TRANSACTION TRUE
WHEN
</programlisting>
</programlisting>
The following are <productname>Postgres</productname>
reserved words which are also <acronym>SQL92</acronym>
or <acronym>SQL3</acronym> reserved words:
The following are <productname>Postgres</productname>
reserved words which are also <acronym>SQL92</acronym>
or <acronym>SQL3</acronym> reserved words:
<programlisting>
<programlisting>
ADD ALL ALTER AND ANY AS ASC
BEGIN BETWEEN BOTH BY
CASCADE CAST CHAR CHARACTER CHECK CLOSE
......@@ -118,49 +130,49 @@ TO TRAILING TRIM
UNION UNIQUE UPDATE USER USING
VALUES VARCHAR VARYING VIEW
WHERE WITH WORK
</programlisting>
</para>
</programlisting>
</para>
<para>
The following are <acronym>SQL92</acronym> reserved key words which
are not <productname>Postgres</productname> reserved key words, but which
if used as function names are always translated into the function
<function>length</function>:
<para>
The following are <acronym>SQL92</acronym> reserved key words which
are not <productname>Postgres</productname> reserved key words, but which
if used as function names are always translated into the function
<function>length</function>:
<programlisting>
<programlisting>
CHAR_LENGTH CHARACTER_LENGTH
</programlisting>
</para>
</programlisting>
</para>
<para>
The following are <acronym>SQL92</acronym> or <acronym>SQL3</acronym>
reserved key words which
are not <productname>Postgres</productname> reserved key words, but
if used as type names are always translated into an alternate, native type:
<para>
The following are <acronym>SQL92</acronym> or <acronym>SQL3</acronym>
reserved key words which
are not <productname>Postgres</productname> reserved key words, but
if used as type names are always translated into an alternate, native type:
<programlisting>
<programlisting>
BOOLEAN DOUBLE FLOAT INT INTEGER INTERVAL REAL SMALLINT
</programlisting>
</para>
<para>
The following are either <acronym>SQL92</acronym>
or <acronym>SQL3</acronym> reserved key words
which are not key words in <productname>Postgres</productname>.
These have no proscribed usage in <productname>Postgres</productname>
at the time of writing (v6.4) but may become reserved key words in the
future:
<note>
<para>
Some of these key words represent functions in <acronym>SQL92</acronym>.
These functions are defined in <productname>Postgres</productname>,
but the parser does not consider the names to be key words and they are allowed
in other contexts.
</para>
</note>
<programlisting>
</programlisting>
</para>
<para>
The following are either <acronym>SQL92</acronym>
or <acronym>SQL3</acronym> reserved key words
which are not key words in <productname>Postgres</productname>.
These have no proscribed usage in <productname>Postgres</productname>
at the time of writing (v6.5) but may become reserved key words in the
future:
<note>
<para>
Some of these key words represent functions in <acronym>SQL92</acronym>.
These functions are defined in <productname>Postgres</productname>,
but the parser does not consider the names to be key words and they are allowed
in other contexts.
</para>
</note>
<programlisting>
ALLOCATE ARE ASSERTION AT AUTHORIZATION AVG
BIT BIT_LENGTH
CASCADED CATALOG COLLATION CONNECT CONNECTION
......@@ -168,7 +180,7 @@ CASCADED CATALOG COLLATION CONNECT CONNECTION
DATE DEALLOCATE DEC DESCRIBE DESCRIPTOR DIAGNOSTICS DISCONNECT DOMAIN
END-EXEC ESCAPE EXCEPT EXCEPTION EXEC EXTERNAL
FIRST FOUND
GET GLOBAL GO GOTO
GET GO GOTO
IDENTITY IMMEDIATE INDICATOR INITIALLY INPUT INTERSECT ISOLATION
LAST LEVEL LOWER
MAX MIN MODULE
......@@ -181,56 +193,56 @@ TEMPORARY TRANSLATE TRANSLATION
UNKNOWN UPPER USAGE
VALUE
WHENEVER WRITE
</programlisting>
</para>
</sect2>
<sect2>
<title>Non-reserved Keywords</title>
<para>
<acronym>SQL92</acronym> and <acronym>SQL3</acronym> have
<firstterm>non-reserved keywords</firstterm> which have
a proscribed meaning in the language but which are also allowed
as identifiers.
<productname>Postgres</productname> has additional keywords
which allow similar unrestricted usage.
In particular, these keywords
are allowed as column or table names.
</para>
<para>
The following are <productname>Postgres</productname>
non-reserved key words which are neither <acronym>SQL92</acronym>
nor <acronym>SQL3</acronym> non-reserved key words:
<programlisting>
AFTER AGGREGATE
</programlisting>
</para>
</sect2>
<sect2>
<title>Non-reserved Keywords</title>
<para>
<acronym>SQL92</acronym> and <acronym>SQL3</acronym> have
<firstterm>non-reserved keywords</firstterm> which have
a proscribed meaning in the language but which are also allowed
as identifiers.
<productname>Postgres</productname> has additional keywords
which allow similar unrestricted usage.
In particular, these keywords
are allowed as column or table names.
</para>
<para>
The following are <productname>Postgres</productname>
non-reserved key words which are neither <acronym>SQL92</acronym>
nor <acronym>SQL3</acronym> non-reserved key words:
<programlisting>
ACCESS AFTER AGGREGATE
BACKWARD BEFORE
CACHE CREATEDB CREATEUSER CYCLE
DATABASE DELIMITERS
EACH ENCODING
EACH ENCODING EXCLUSIVE
FORWARD FUNCTION
HANDLER
INCREMENT INDEX INHERITS INSENSITIVE INSTEAD ISNULL
LANCOMPILER LOCATION
MAXVALUE MINVALUE
MAXVALUE MINVALUE MODE
NOCREATEDB NOCREATEUSER NOTHING NOTNULL
OIDS OPERATOR
PASSWORD PROCEDURAL
RECIPE RENAME RETURNS ROW RULE
SEQUENCE SERIAL START STATEMENT STDIN STDOUT
SEQUENCE SERIAL SHARE START STATEMENT STDIN STDOUT
TRUSTED
VALID VERSION
</programlisting>
</para>
</programlisting>
</para>
<para>
The following are <productname>Postgres</productname>
non-reserved key words which are <acronym>SQL92</acronym>
or <acronym>SQL3</acronym> reserved key words:
<para>
The following are <productname>Postgres</productname>
non-reserved key words which are <acronym>SQL92</acronym>
or <acronym>SQL3</acronym> reserved key words:
<programlisting>
<programlisting>
ABSOLUTE ACTION
DAY
HOUR
......@@ -246,30 +258,30 @@ SCROLL SECOND
TIME TIMESTAMP TIMEZONE_HOUR TIMEZONE_MINUTE TRIGGER
YEAR
ZONE
</programlisting>
</para>
</programlisting>
</para>
<para>
The following are <productname>Postgres</productname>
non-reserved key words which are also either <acronym>SQL92</acronym>
or <acronym>SQL3</acronym> non-reserved key words:
<para>
The following are <productname>Postgres</productname>
non-reserved key words which are also either <acronym>SQL92</acronym>
or <acronym>SQL3</acronym> non-reserved key words:
<programlisting>
TYPE
</programlisting>
</para>
<programlisting>
COMMITTED SERIALIZABLE TYPE
</programlisting>
</para>
<para>
The following are either <acronym>SQL92</acronym>
or <acronym>SQL3</acronym> non-reserved key words which are not
key words of any kind in <productname>Postgres</productname>:
<para>
The following are either <acronym>SQL92</acronym>
or <acronym>SQL3</acronym> non-reserved key words which are not
key words of any kind in <productname>Postgres</productname>:
<programlisting>
<programlisting>
ADA
C CATALOG_NAME CHARACTER_SET_CATALOG CHARACTER_SET_NAME
CHARACTER_SET_SCHEMA CLASS_ORIGIN COBOL COLLATION_CATALOG
COLLATION_NAME COLLATION_SCHEMA COLUMN_NAME
COMMAND_FUNCTION COMMITTED CONDITION_NUMBER
COMMAND_FUNCTION CONDITION_NUMBER
CONNECTION_NAME CONSTRAINT_CATALOG CONSTRAINT_NAME
CONSTRAINT_SCHEMA CURSOR_NAME
DATA DATE_TIME_INTERVAL_CODE DATE_TIME_INTERVAL_PRECISION
......@@ -281,15 +293,29 @@ NAME NULLABLE NUMBER
PAD PASCAL PLI
REPEATABLE RETURNED_LENGTH RETURNED_OCTET_LENGTH
RETURNED_SQLSTATE ROW_COUNT
SCALE SCHEMA_NAME SERIALIZABLE SERVER_NAME SPACE
SCALE SCHEMA_NAME SERVER_NAME SPACE
SUBCLASS_ORIGIN
TABLE_NAME
UNCOMMITTED UNNAMED
</programlisting>
</para>
</sect2>
</sect1>
</chapter>
</programlisting>
</para>
</sect2>
</sect1>
<sect1>
<title>Expressions</title>
<para>
<acronym>SQL92</acronym> allows <firstterm>expressions</firstterm>
to transform data in expressions. Expressions may contain operators
(see <xref linkend="operators-title" endterm="operators-title">
for more details) and functions
(<xref linkend="functions-title" endterm="functions-title"> has
more information).
</para>
</sect1>
</chapter>
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