diff options
Diffstat (limited to 'doc/src/sgml/ref/create_function.sgml')
| -rw-r--r-- | doc/src/sgml/ref/create_function.sgml | 127 |
1 files changed, 59 insertions, 68 deletions
diff --git a/doc/src/sgml/ref/create_function.sgml b/doc/src/sgml/ref/create_function.sgml index 3dc37e3380d..7ba3391a669 100644 --- a/doc/src/sgml/ref/create_function.sgml +++ b/doc/src/sgml/ref/create_function.sgml @@ -32,41 +32,34 @@ CREATE FUNCTION <replaceable class="parameter">name</replaceable> ( [ <replaceab Inputs </title> <para> - <variablelist> - <varlistentry> - <term> - <replaceable class="parameter">name</replaceable> - </term> - <listitem> - <para> - The name of a function to create. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term> - <replaceable class="parameter">ftype</replaceable> - </term> - <listitem> - <para> - The data type of function arguments. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term> - <replaceable class="parameter">rtype</replaceable> - </term> - <listitem> - <para> - The return data type. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term> - <replaceable class="parameter">definition</replaceable> - </term> + + <variablelist> + <varlistentry> + <term><replaceable class="parameter">name</replaceable></term> + <listitem> + <para> + The name of a function to create. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term><replaceable class="parameter">ftype</replaceable></term> + <listitem> + <para> + The data type of function arguments. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term><replaceable class="parameter">rtype</replaceable></term> + <listitem> + <para> + The return data type. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term><replaceable class="parameter">definition</replaceable></term> <listitem> <para> A string defining the function; the meaning depends on the language. @@ -76,9 +69,7 @@ CREATE FUNCTION <replaceable class="parameter">name</replaceable> ( [ <replaceab </listitem> </varlistentry> <varlistentry> - <term> - <replaceable class="parameter">langname</replaceable> - </term> + <term><replaceable class="parameter">langname</replaceable></term> <listitem> <para> may be '<literal>C</literal>', '<literal>sql</literal>', @@ -93,7 +84,7 @@ CREATE FUNCTION <replaceable class="parameter">name</replaceable> ( [ <replaceab </variablelist> </para> </refsect2> - + <refsect2 id="R2-SQL-CREATEFUNCTION-2"> <refsect2info> <date>1998-09-09</date> @@ -102,12 +93,12 @@ CREATE FUNCTION <replaceable class="parameter">name</replaceable> ( [ <replaceab Outputs </title> <para> - + <variablelist> <varlistentry> - <term> - <returnvalue>CREATE</returnvalue> - </term> + <term><computeroutput> +CREATE + </computeroutput></term> <listitem> <para> This is returned if the command completes successfully. @@ -118,7 +109,7 @@ CREATE FUNCTION <replaceable class="parameter">name</replaceable> ( [ <replaceab </para> </refsect2> </refsynopsisdiv> - + <refsect1 id="R1-SQL-CREATEFUNCTION-1"> <refsect1info> <date>1998-09-09</date> @@ -188,20 +179,21 @@ in the <citetitle>PostgreSQL Programmer's Guide</citetitle> </title> <para> To create a simple SQL function: - </para> + <programlisting> - CREATE FUNCTION one() RETURNS int4 - AS 'SELECT 1 AS RESULT' - LANGUAGE 'sql'; - - SELECT one() AS answer; - +CREATE FUNCTION one() RETURNS int4 + AS 'SELECT 1 AS RESULT' + LANGUAGE 'sql'; +SELECT one() AS answer; + <computeroutput> answer ------ 1 </computeroutput> </programlisting> + </para> + <para> To create a C function, calling a routine from a user-created shared library. This particular routine calculates a check @@ -210,16 +202,16 @@ in the <citetitle>PostgreSQL Programmer's Guide</citetitle> </para> <programlisting> <userinput> - CREATE FUNCTION ean_checkdigit(bpchar, bpchar) RETURNS bool - AS '/usr1/proj/bray/sql/funcs.so' LANGUAGE 'c'; +CREATE FUNCTION ean_checkdigit(bpchar, bpchar) RETURNS bool + AS '/usr1/proj/bray/sql/funcs.so' LANGUAGE 'c'; - CREATE TABLE product ( +CREATE TABLE product ( id char(8) PRIMARY KEY, eanprefix char(8) CHECK (eanprefix ~ '[0-9]{2}-[0-9]{5}') REFERENCES brandname(ean_prefix), eancode char(6) CHECK (eancode ~ '[0-9]{6}'), CONSTRAINT ean CHECK (ean_checkdigit(eanprefix, eancode)) - ); +); </userinput> </programlisting> </refsect1> @@ -232,16 +224,16 @@ in the <citetitle>PostgreSQL Programmer's Guide</citetitle> A C function cannot return a set of values. </para> </refsect1> - + <refsect1 id="R1-SQL-CREATEFUNCTION-4"> <title> Compatibility </title> - <para> - <command>CREATE FUNCTION</command> is - a <productname>Postgres</productname> language extension. + <para> + <command>CREATE FUNCTION</command> is + a <productname>Postgres</productname> language extension. </para> - + <refsect2 id="R2-SQL-CREATEFUNCTION-4"> <refsect2info> <date>1998-09-09</date> @@ -251,27 +243,26 @@ in the <citetitle>PostgreSQL Programmer's Guide</citetitle> </title> <para> -<note> + <note> <para> PSM stands for Persistent Stored Modules. It is a procedural language and it was originally hoped that PSM would be ratified as an official standard by late 1996. As of mid-1998, this -has not yet happened, but it is hoped that PSM will + has not yet happened, but it is hoped that PSM will eventually become a standard. </para> -</note> + </note> -SQL/PSM <command>CREATE FUNCTION</command> has the following syntax: -<synopsis> + SQL/PSM <command>CREATE FUNCTION</command> has the following syntax: + <synopsis> CREATE FUNCTION <replaceable class="parameter">name</replaceable> - ( [ [ IN | OUT | INOUT ] <replaceable class="parameter">eter</replaceable>eable> <replaceable + ( [ [ IN | OUT | INOUT ] <replaceable class="parameter">eter</replaceable>eable>eable> <replaceable class="parameter">type</replaceable> [, ...] ] ) RETURNS <replaceable class="parameter">rtype</replaceable> LANGUAGE '<replaceable class="parameter">langname</replaceable>' ESPECIFIC <replaceable class="parameter">routine</replaceable> <replaceable class="parameter">SQL-statement</replaceable> -</synopsis> - + </synopsis> </para> </refsect2> </refsect1> |