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<chapter id="functions">
<title id="functions-title">Functions</title>
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<abstract>
<para>
Describes the built-in functions available
in <productname>Postgres</productname>.
</para>
</abstract>
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<para>
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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.
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</para>
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<sect1>
<title id="sql-funcs">SQL Functions</title>
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<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>
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<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">r"</replaceable>le>, <replaceable
class="parameter">c2</replaceable> + 5, 0) </entry>
</row>
<row>
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<entry> NULLIF(<replaceable class="parameter">input</replaceable>,<replaceable class="parameter">value</replaceable>) </entry>
<entry> <replaceable class="parameter">input</replaceable> or NULL </entry>
<entry> return NULL if <replaceable class="parameter">input</replaceable> = <replaceable class="parameter">value</replaceable> </entry>
<entry> NULLIF(<replaceable class="parameter">c1</replaceable>, 'N/A')</entry>
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</row>
<row>
<entry> CASE WHEN <replaceable class="parameter">expr</replaceable> THEN <replaceable class="parameter">expr</replaceable> [...] ELSE <replaceable class="parameter">expr</replaceable> END </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' END </entry>
</row>
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</tbody>
</tgroup>
</table>
</para>
</sect1>
<sect1>
<title id="math-funcs">Mathematical Functions</title>
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<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>
<row>
<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>
</row>
<row>
<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>
</row>
<row>
<entry> integer(float) </entry>
<entry> int </entry>
<entry> convert floating point to integer </entry>
<entry> integer(2.0) </entry>
</row>
</tbody>
</tgroup>
</table>
</para>
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</sect1>
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<sect1>
<title>String Functions</title>
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<para>
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SQL92 defines string functions with specific syntax. Some of these
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are implemented using other <productname>Postgres</productname> functions.
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The supported string types for <acronym>SQL92</acronym> are
<type>char</type>, <type>varchar</type>, and <type>text</type>.
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</para>
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<para>
<table tocentry="1">
<title><acronym>SQL92</acronym> String Functions</title>
<tgroup cols="4">
<thead>
<row>
<entry>Function</entry>
<entry>Returns</entry>
<entry>Description</entry>
<entry>Example</entry>
</row>
</thead>
<tbody>
<row>
<entry> char_length(string) </entry>
<entry> int4 </entry>
<entry> length of string </entry>
<entry> char_length('jose') </entry>
</row>
<row>
<entry> character_length(string) </entry>
<entry> int4 </entry>
<entry> length of string </entry>
<entry> char_length('jose') </entry>
</row>
<row>
<entry> lower(string) </entry>
<entry> string </entry>
<entry> convert string to lower case </entry>
<entry> lower('TOM') </entry>
</row>
<row>
<entry> octet_length(string) </entry>
<entry> int4 </entry>
<entry> storage length of string </entry>
<entry> octet_length('jose') </entry>
</row>
<row>
<entry> position(string in string) </entry>
<entry> int4 </entry>
<entry> location of specified substring </entry>
<entry> position('o' in 'Tom') </entry>
</row>
<row>
<entry> substring(string [from int] [for int]) </entry>
<entry> string </entry>
<entry> extract specified substring </entry>
<entry> substring('Tom' from 2 for 2) </entry>
</row>
<row>
<entry> trim([leading|trailing|both] [string] from string) </entry>
<entry> string </entry>
<entry> trim characters from string </entry>
<entry> trim(both 'x' from 'xTomx') </entry>
</row>
<row>
<entry> upper(text) </entry>
<entry> text </entry>
<entry> convert text to upper case </entry>
<entry> upper('tom') </entry>
</row>
</tbody>
</tgroup>
</table>
</para>
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<para>
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Many additional string functions are available for text, varchar(), and char() types.
Some are used internally to implement the SQL92 string functions listed above.
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</para>
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<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>
<row>
<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>
</row>
<row>
<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>
</row>
<row>
<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>
</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>
</row>
<row>
<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>
</row>
<row>
<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>
</row>
<row>
<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>
</row>
<row>
<entry> varchar(text) </entry>
<entry> varchar </entry>
<entry> convert text to varchar type </entry>
<entry> varchar('text string') </entry>
</row>
</tbody>
</tgroup>
</table>
</para>
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<para>
Most functions explicitly defined for text will work for char() and varchar() arguments.
</para>
</sect1>
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<sect1>
<title>Date/Time Functions</title>
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<para>
The date/time functions provide a powerful set of tools
for manipulating various date/time types.
</para>
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<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>
<row>
<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> preserve 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>
</row>
<row>
<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>
</row>
<row>
<entry> date_part(text,datetime) </entry>
<entry> float8 </entry>
<entry> portion of date </entry>
<entry> date_part('dow','now'::datetime) </entry>
</row>
<row>
<entry> date_part(text,timespan) </entry>
<entry> float8 </entry>
<entry> portion of time </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 </entry>
<entry> date_trunc('month','now'::abstime) </entry>
</row>
<row>
<entry> isfinite(abstime) </entry>
<entry> bool </entry>
<entry> a finite time? </entry>
<entry> isfinite('now'::abstime) </entry>
</row>
<row>
<entry> isfinite(datetime) </entry>
<entry> bool </entry>
<entry> a finite time? </entry>
<entry> isfinite('now'::datetime) </entry>
</row>
<row>
<entry> isfinite(timespan) </entry>
<entry> bool </entry>
<entry> 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>
</row>
<row>
<entry> timespan(reltime) </entry>
<entry> timespan </entry>
<entry> convert to timespan </entry>
<entry> timespan('4 hours'::reltime) </entry>
</row>
</tbody>
</tgroup>
</table>
</para>
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<para>
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For the
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<function>date_part</function> and <function>date_trunc</function>
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functions, arguments can be
`year', `month', `day', `hour', `minute', and `second',
as well as the more specialized quantities
`decade', `century', `millenium', `millisecond', and `microsecond'.
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<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>
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</sect1>
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as attache of this mail is patch (to the main tree) with to_char's
family functions. Contain:
conversion from a datetype to formatted text:
to_char( datetime, text)
to_char( timestamp, text)
to_char( int4, text)
to_char( int8, text)
to_char( float4, text)
to_char( float8, text)
to_char( numeric, text)
vice versa:
to_date ( text, text)
to_datetime ( text, text)
to_timestamp ( text, text)
to_number ( text, text) (convert to numeric)
PostgreSQL to_char is very compatible with Oracle's to_char(), but not
total exactly (now). Small differentions are in number formating. It will
fix in next to_char() version.
! If will this patch aplly to the main tree, must be delete the current
to_char version in contrib (directory "dateformat" and note in contrib's
README), this patch not erase it (sorry Bruce).
The patch patching files:
doc/src/sgml/func.sgml
^^^^^^^^
Hmm, I'm not sure if my English... :( Check it anyone (volunteer)?
Thomas, it is right? SGML is not my primary lang and compile
the current PG docs tree is very happy job (hard variables setting in
docs/sgml/Makefile --> HSTYLE= /home/users/t/thomas/.... :-)
What add any definition to global configure.in and set Makefiles in docs
tree via ./configure?
src/backend/utils/adt/Makefile
src/backend/utils/adt/formatting.c
src/include/catalog/pg_proc.h
src/include/utils/formatting.h
Karel Zak <zakkr@zf.jcu.cz> http://home.zf.jcu.cz/~zakkr/
2000-01-26 00:53:56 +01:00
<sect1>
<title id="formatting-funcs"> Formatting Functions </title>
<note>
<title>Author</title>
<para>
Written by
<ulink url="mailto:zakkr@zf.jcu.cz">Karel Zak</ulink>
on 2000-01-24.
</para>
</note>
<para>
Formatting functions provide a powerful set of tools for converting
various datetypes (date/time, int, float, numeric) to formatted strings
and reverse convert from formatted strings to original datetypes.
</para>
<para>
<table tocentry="1">
<title>Formatting Functions</title>
<tgroup cols="4">
<thead>
<row>
<entry>Function</entry>
<entry>Returns</entry>
<entry>Description</entry>
<entry>Example</entry>
</row>
</thead>
<tbody>
<row>
<entry> to_char(datetime, text) </entry>
<entry> text </entry>
<entry> convert datetime to string </entry>
<entry> to_char('now'::datetime, 'HH12:MI:SS') </entry>
</row>
<row>
<entry> to_char(timestamp, text) </entry>
<entry> text </entry>
<entry> convert timestamp to string </entry>
<entry> to_char( now(), 'HH12:MI:SS') </entry>
</row>
<row>
<entry> to_char(int, text) </entry>
<entry> text </entry>
<entry> convert int4/int8 to string </entry>
<entry> to_char(125, '999') </entry>
</row>
<row>
<entry> to_char(float, text) </entry>
<entry> text </entry>
<entry> convert float4/float8 to string </entry>
<entry> to_char(125.8, '999D9') </entry>
</row>
<row>
<entry> to_char(numeric, text) </entry>
<entry> text </entry>
<entry> convert numeric to string </entry>
<entry> to_char(-125.8, '999D99S') </entry>
</row>
<row>
<entry> to_datetime(text, text) </entry>
<entry> datetime </entry>
<entry> convert string to datetime </entry>
<entry> to_datetime('05 Dec 2000 13', 'DD Mon YYYY HH') </entry>
</row>
<row>
<entry> to_date(text, text) </entry>
<entry> date </entry>
<entry> convert string to date </entry>
<entry> to_date('05 Dec 2000', 'DD Mon YYYY') </entry>
</row>
<row>
<entry> to_timestamp(text, text) </entry>
<entry> date </entry>
<entry> convert string to timestamp </entry>
<entry> to_timestamp('05 Dec 2000', 'DD Mon YYYY') </entry>
</row>
<row>
<entry> to_number(text, text) </entry>
<entry> numeric </entry>
<entry> convert string to numeric </entry>
<entry> to_number('12,454.8-', '99G999D9S') </entry>
</row>
</tbody>
</tgroup>
</table>
</para>
<para>
For all formatting functions is second argument format-picture.
</para>
<para>
<table tocentry="1">
<title>Format-pictures for datetime to_char() version.</title>
<tgroup cols="2">
<thead>
<row>
<entry>Format-picture</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry> HH </entry>
<entry> hour of day (01-12) </entry>
</row>
<row>
<entry> HH12 </entry>
<entry> hour of day (01-12) </entry>
</row>
<row>
<entry> MI </entry>
<entry> minute (00-59) </entry>
</row>
<row>
<entry> SS </entry>
<entry> socond (00-59) </entry>
</row>
<row>
<entry> SSSS </entry>
<entry> seconds past midnight (0-86399) </entry>
</row>
<row>
<entry> Y,YYY </entry>
<entry> year (4 and more digits) with comma </entry>
</row>
<row>
<entry> YYYY </entry>
<entry> year (4 and more digits) </entry>
</row>
<row>
<entry> YYY </entry>
<entry> last 3 digits of year </entry>
</row>
<row>
<entry> YY </entry>
<entry> last 2 digits of year </entry>
</row>
<row>
<entry> Y </entry>
<entry> last digit of year </entry>
</row>
<row>
<entry> MONTH </entry>
<entry> full month name (9-letters) - all characters is upper </entry>
</row>
<row>
<entry> Month </entry>
<entry> full month name (9-letters) - first character is upper </entry>
</row>
<row>
<entry> month </entry>
<entry> full month name (9-letters) - all characters is lower </entry>
</row>
<row>
<entry> MON </entry>
<entry> abbreviated month name (3-letters) - all characters is upper </entry>
</row>
<row>
<entry> Mon </entry>
<entry> abbreviated month name (3-letters) - first character is upper </entry>
</row>
<row>
<entry> mon </entry>
<entry> abbreviated month name (3-letters) - all characters is lower </entry>
</row>
<row>
<entry> MM </entry>
<entry> month (01-12) </entry>
</row>
<row>
<entry> DAY </entry>
<entry> full day name (9-letters) - all characters is upper </entry>
</row>
<row>
<entry> Day </entry>
<entry> full day name (9-letters) - first character is upper </entry>
</row>
<row>
<entry> day </entry>
<entry> full day name (9-letters) - all characters is lower </entry>
</row>
<row>
<entry> DY </entry>
<entry> abbreviated day name (3-letters) - all characters is upper </entry>
</row>
<row>
<entry> Dy </entry>
<entry> abbreviated day name (3-letters) - first character is upper </entry>
</row>
<row>
<entry> dy </entry>
<entry> abbreviated day name (3-letters) - all characters is upper </entry>
</row>
<row>
<entry> DDD </entry>
<entry> day of year (001-366) </entry>
</row>
<row>
<entry> DD </entry>
<entry> day of month (01-31) </entry>
</row>
<row>
<entry> D </entry>
<entry> day of week (1-7; SUN=1) </entry>
</row>
<row>
<entry> W </entry>
<entry> week of month </entry>
</row>
<row>
<entry> WW </entry>
<entry> week number of year </entry>
</row>
<row>
<entry> CC </entry>
<entry> century (2-digits) </entry>
</row>
<row>
<entry> J </entry>
<entry> julian day (days since January 1, 4712 BC) </entry>
</row>
<row>
<entry> Q </entry>
<entry> quarter </entry>
</row>
<row>
<entry> RM </entry>
<entry> month in roman numeral (I-XII; I=JAN) </entry>
</row>
</tbody>
</tgroup>
</table>
</para>
<para>
All format-pictures allow use suffixes (postfix / prefix). The suffix is
always valid for near format-picture. The 'FX' is global prefix only.
</para>
<para>
<table tocentry="1">
<title>Suffixes for format-pictures for datetime to_char() version.</title>
<tgroup cols="3">
<thead>
<row>
<entry>Suffix</entry>
<entry>Description</entry>
<entry>Example</entry>
</row>
</thead>
<tbody>
<row>
<entry> FM </entry>
<entry> fill mode - prefix </entry>
<entry> FMMonth </entry>
</row>
<row>
<entry> TH </entry>
<entry> upper ordinal number - postfix </entry>
<entry> DDTH </entry>
</row>
<row>
<entry> th </entry>
<entry> lower ordinal number - postfix </entry>
<entry> DDTH </entry>
</row>
<row>
<entry> FX </entry>
<entry> FX - (Fixed format) global format-picture switch.
the TO_DATETIME / TO_DATA skip blank space if this option is
not use. Must by used as first item in formt-picture. </entry>
<entry> FX Month DD Day </entry>
</row>
<row>
<entry> SP </entry>
<entry> spell mode (not implement now)</entry>
<entry> DDSP </entry>
</row>
</tbody>
</tgroup>
</table>
</para>
<para>
'\' - must be use as double \\, example '\\HH\\MI\\SS'
</para>
<para>
'"' - string between a quotation marks is skipen and not is parsed.
If you want write '"' to output you must use \\", exapmle '\\"YYYY Month\\"'.
</para>
<para>
text - the PostgreSQL's to_char() support text without '"', but string
between a quotation marks is fastly and you have guarantee, that a text
not will interpreted as a keyword (format-picture), exapmle '"Hello Year: "YYYY'.
</para>
<para>
<table tocentry="1">
<title>Format-pictures for number (int/float/numeric) to_char() version.</title>
<tgroup cols="2">
<thead>
<row>
<entry>Format-picture</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry> 9 </entry>
<entry> return value with the specified number of digits, and if digit is
not available use blank space </entry>
</row>
<row>
<entry> 0 </entry>
<entry> as 9, but instead blank space use zero </entry>
</row>
<row>
<entry> . (period) </entry>
<entry> decimal point </entry>
</row>
<row>
<entry> , (comma) </entry>
<entry> group (thousand) separator </entry>
</row>
<row>
<entry> PR </entry>
<entry> return negative value in angle brackets </entry>
</row>
<row>
<entry> S </entry>
<entry> return negatice value with minus sign (use locales) </entry>
</row>
<row>
<entry> L </entry>
<entry> currency symbol (use locales) </entry>
</row>
<row>
<entry> D </entry>
<entry> decimal point (use locales) </entry>
</row>
<row>
<entry> G </entry>
<entry> group separator (use locales) </entry>
</row>
<row>
<entry> MI </entry>
<entry> return minus sign on specified position (if number < 0) </entry>
</row>
<row>
<entry> PL </entry>
<entry> return plus sign on specified position (if number > 0) </entry>
</row>
<row>
<entry> RN </entry>
<entry> return number as roman number (number must be between 1 and 3999) </entry>
</row>
<row>
<entry> TH or th </entry>
<entry> convert number to ordinal number (not convert numbers under zero and decimal numbers) </entry>
</row>
<row>
<entry> V </entry>
<entry> arg1 * (10 ^ n); - return a value multiplied by 10^n (where 'n' is number of '9's after the 'V').
The to_char() not support use 'V' and decimal poin together, example "99.9V99". </entry>
</row>
<row>
<entry> EEEE </entry>
<entry> science numbers. Now not supported. </entry>
</row>
</tbody>
</tgroup>
</table>
</para>
<para>
The PostgreSQL to_char() not support absurd to_char(0.1, '99.99')
--> <ProgramListing> ' .10' </ProgramListing> format.
</para>
<para>
<table tocentry="1">
<title> The to_char() examples. </title>
<tgroup cols="2">
<thead>
<row>
<entry>Input</entry>
<entry>Output</entry>
</row>
</thead>
<tbody>
<row>
<entry> to_char(now(), 'Day, HH12:MI:SS') </entry>
<entry><ProgramListing> 'Tuesday , 05:39:18' </ProgramListing></entry>
</row>
<row>
<entry> to_char(now(), 'FMDay, HH12:MI:SS') </entry>
<entry><ProgramListing> 'Tuesday, 05:39:18' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 0.1, '99.99') </entry>
<entry><ProgramListing> ' 0.10' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 0.1, '0.9') </entry>
<entry><ProgramListing> ' 0.1' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 0.1, '090.9') </entry>
<entry><ProgramListing> ' 000.1' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 485, '999') </entry>
<entry><ProgramListing> ' 485' </ProgramListing></entry>
</row>
<row>
<entry> to_char( -485, '999') </entry>
<entry><ProgramListing> '-485' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 485, '09999') </entry>
<entry><ProgramListing> ' 00485' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 485, 'FM09999') </entry>
<entry><ProgramListing> '00485' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 485, 'FM999') </entry>
<entry><ProgramListing> '485' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 485, '9 9 9') </entry>
<entry><ProgramListing> ' 4 8 5' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 1485, '9,999') </entry>
<entry><ProgramListing> ' 1,485' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 1485, '9G999') </entry>
<entry><ProgramListing> ' 1 485' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 148.5, '999.999') </entry>
<entry><ProgramListing> ' 148.500' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 148.5, '999D999') </entry>
<entry><ProgramListing> ' 148,500' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 3148.5,'9G999D999') </entry>
<entry><ProgramListing> ' 3 148,500' </ProgramListing></entry>
</row>
<row>
<entry> to_char( -485, '999S') </entry>
<entry><ProgramListing> '485-' </ProgramListing></entry>
</row>
<row>
<entry> to_char( -485, '999MI') </entry>
<entry><ProgramListing> '485-' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 485, '999MI') </entry>
<entry><ProgramListing> '485' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 485, 'PL999') </entry>
<entry><ProgramListing> '+485' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 485, 'SG999') </entry>
<entry><ProgramListing> '+485' </ProgramListing></entry>
</row>
<row>
<entry> to_char( -485, 'SG999') </entry>
<entry><ProgramListing> '-485' </ProgramListing></entry>
</row>
<row>
<entry> to_char( -485, '9SG99') </entry>
<entry><ProgramListing> '4-85' </ProgramListing></entry>
</row>
<row>
<entry> to_char( -485, '999PR') </entry>
<entry><ProgramListing> '<485>' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 485, 'L999') </entry>
<entry><ProgramListing> 'DM 485' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 485, 'RN') </entry>
<entry><ProgramListing> ' CDLXXXV' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 485, 'FMRN') </entry>
<entry><ProgramListing> 'CDLXXXV' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 5.2, 'FMRN') </entry>
<entry><ProgramListing> 'V' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 482, '999th') </entry>
<entry><ProgramListing> ' 482nd' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 485, '"Good number:"999') </entry>
<entry><ProgramListing> 'Good number: 485' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 485.8, '"Pre-decimal:"999" Post-decimal:" .999') </entry>
<entry><ProgramListing> 'Pre-decimal: 485 Post-decimal: .800' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 12, '99V999') </entry>
<entry><ProgramListing> ' 12000' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 12.4, '99V999') </entry>
<entry><ProgramListing> ' 12400' </ProgramListing></entry>
</row>
<row>
<entry> to_char( 12.45, '99V9') </entry>
<entry><ProgramListing> ' 125' </ProgramListing></entry>
</row>
</tbody>
</tgroup>
</table>
</para>
</sect1>
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<sect1>
<title>Geometric Functions</title>
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<para>
The geometric types point, box, lseg, line, path, polygon, and
circle have a large set of native support functions.
</para>
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1999-06-14 09:36:12 +02:00
<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>
<row>
<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>
</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>
</row>
<row>
<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>
</row>
<row>
<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>
</row>
<row>
<entry> isclosed(path) </entry>
<entry> bool </entry>
<entry> a closed path? </entry>
<entry> isclosed('((0,0),(1,1),(2,0))'::path) </entry>
</row>
<row>
<entry> isopen(path) </entry>
<entry> bool </entry>
<entry> 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>
</row>
<row>
<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 </entry>
<entry> popen('[(0,0),(1,1),(2,0)]'::path) </entry>
</row>
<row>
<entry> point(lseg,lseg) </entry>
<entry> point </entry>
<entry> 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 </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 </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>
</row>
<row>
<entry> width(box) </entry>
<entry> float8 </entry>
<entry> horizontal size </entry>
<entry> width('((0,0),(1,1))'::box) </entry>
</row>
</tbody>
</tgroup>
</table>
</para>
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<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>
<row>
<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>
</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>
</row>
<row>
<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>
</row>
<row>
<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>
</row>
<row>
<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>
</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>
</row>
<row>
<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>
</row>
<row>
<entry> polygon(circle) </entry>
<entry> polygon </entry>
<entry> convert to 12-point polygon </entry>
<entry> polygon('((0,0),2.0)'::circle) </entry>
</row>
<row>
<entry> polygon(<replaceable class="parameter">npts</replaceable>,circle) </entry>
<entry> polygon </entry>
<entry> convert to <replaceable class="parameter">npts</replaceable> polygon </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>
</row>
</tbody>
</tgroup>
</table>
</para>
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<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>
<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>
</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>
</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>
</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>
</row>
</tbody>
</tgroup>
</table>
</para>
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</sect1>
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<sect1>
<title id="cidr-funcs">IP V4 Functions</title>
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<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>
<row>
<entry> broadcast(cidr) </entry>
<entry> text </entry>
<entry> construct broadcast address as text </entry>
<entry> broadcast('192.168.1.5/24') </entry>
</row>
<row>
<entry> broadcast(inet) </entry>
<entry> text </entry>
<entry> construct broadcast address as text </entry>
<entry> broadcast('192.168.1.5/24') </entry>
</row>
<row>
<entry> host(inet) </entry>
<entry> text </entry>
<entry> extract host address as text </entry>
<entry> host('192.168.1.5/24') </entry>
</row>
<row>
<entry> masklen(cidr) </entry>
<entry> int4 </entry>
<entry> calculate netmask length </entry>
<entry> masklen('192.168.1.5/24') </entry>
</row>
<row>
<entry> masklen(inet) </entry>
<entry> int4 </entry>
<entry> calculate netmask length </entry>
<entry> masklen('192.168.1.5/24') </entry>
</row>
<row>
<entry> netmask(inet) </entry>
<entry> text </entry>
<entry> construct netmask as text </entry>
<entry> netmask('192.168.1.5/24') </entry>
</row>
</tbody>
</tgroup>
</table>
</para>
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</sect1>
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</chapter>
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