diff options
Diffstat (limited to 'doc/src/sgml/ref/create_function.sgml')
| -rw-r--r-- | doc/src/sgml/ref/create_function.sgml | 126 |
1 files changed, 66 insertions, 60 deletions
diff --git a/doc/src/sgml/ref/create_function.sgml b/doc/src/sgml/ref/create_function.sgml index e639845a7c5..f5a27adb308 100644 --- a/doc/src/sgml/ref/create_function.sgml +++ b/doc/src/sgml/ref/create_function.sgml @@ -12,7 +12,7 @@ <REFPURPOSE> Defines a new function </REFPURPOSE> - + </refnamediv> <REFSYNOPSISDIV> <REFSYNOPSISDIVINFO> <DATE>1998-09-09</DATE> @@ -66,30 +66,31 @@ CREATE FUNCTION <replaceable class="parameter">name</replaceable> ( [ <replaceab <VARLISTENTRY> <TERM> <replaceable class="parameter">path</replaceable> - </TERM> - <LISTITEM> - <PARA> - May be either an SQL-query or an absolute path to an - object file. - </PARA> - </LISTITEM> - </VARLISTENTRY> - <VARLISTENTRY> - <TERM> - <replaceable class="parameter">langname</replaceable> - </TERM> - <LISTITEM> - <PARA> - may be '<literal>C</literal>', '<literal>sql</literal>', - '<literal>internal</literal>' - or '<replaceable class="parameter">plname</replaceable>', - where '<replaceable class="parameter">plname</replaceable>' - is the name of a created procedural - language. See <command>CREATE LANGUAGE</command> for details. - </PARA> - </LISTITEM> - </VARLISTENTRY> - </variablelist> + </TERM> + <LISTITEM> + <PARA> + May be either an SQL-query or an absolute path to an + object file. + </PARA> + </LISTITEM> + </VARLISTENTRY> + <VARLISTENTRY> + <TERM> + <replaceable class="parameter">langname</replaceable> + </TERM> + <LISTITEM> + <PARA> + may be '<literal>C</literal>', '<literal>sql</literal>', + '<literal>internal</literal>' + or '<replaceable class="parameter">plname</replaceable>', + where '<replaceable class="parameter">plname</replaceable>' + is the name of a created procedural + language. See <command>CREATE LANGUAGE</command> for details. + </PARA> + </LISTITEM> + </VARLISTENTRY> + </variablelist> + </para> </REFSECT2> <REFSECT2 ID="R2-SQL-CREATEFUNCTION-2"> @@ -100,16 +101,20 @@ CREATE FUNCTION <replaceable class="parameter">name</replaceable> ( [ <replaceab Outputs </TITLE> <PARA> - - <VARIABLELIST> - <VARLISTENTRY> - <TERM> - <ReturnValue>CREATE</ReturnValue> - </TERM> - <LISTITEM> - <PARA> - This is returned if the command completes successfully. - </VARIABLELIST> + + <VARIABLELIST> + <VARLISTENTRY> + <TERM> + <ReturnValue>CREATE</ReturnValue> + </TERM> + <LISTITEM> + <PARA> + This is returned if the command completes successfully. + </para> + </listitem> + </varlistentry> + </VARIABLELIST> + </para> </REFSECT2> </REFSYNOPSISDIV> @@ -122,8 +127,8 @@ CREATE FUNCTION <replaceable class="parameter">name</replaceable> ( [ <replaceab </TITLE> <PARA> <command>CREATE FUNCTION</command> allows a -<productname>Postgres</productname> user -to register a function + <productname>Postgres</productname> user + to register a function with a database. Subsequently, this user is treated as the owner of the function. </PARA> @@ -138,13 +143,14 @@ to register a function <PARA> Refer to the chapter on functions in the <citetitle>PostgreSQL Programmer's Guide</citetitle> - for further information. + for further information. </PARA> <PARA> Use <command>DROP FUNCTION</command> to drop user-defined functions. </PARA> </REFSECT2> + </refsect1> <REFSECT1 ID="R1-SQL-CREATEFUNCTION-2"> <TITLE> @@ -154,17 +160,17 @@ in the <citetitle>PostgreSQL Programmer's Guide</citetitle> To create a simple SQL function: </PARA> <ProgramListing> -CREATE FUNCTION one() RETURNS int4 - AS 'SELECT 1 AS RESULT' - LANGUAGE 'sql'; - -SELECT one() AS answer; - -<computeroutput> -answer ------- -1 -</computeroutput> + CREATE FUNCTION one() RETURNS int4 + AS 'SELECT 1 AS RESULT' + LANGUAGE 'sql'; + + SELECT one() AS answer; + + <computeroutput> + answer + ------ + 1 + </computeroutput> </ProgramListing> <para> To create a C function, calling a routine from a user-created @@ -173,18 +179,18 @@ answer is correct. It is intended for use in a CHECK contraint. </para> <programlisting> -<userinput> -CREATE FUNCTION ean_checkdigit(bpchar, bpchar) RETURNS bool + <userinput> + CREATE FUNCTION ean_checkdigit(bpchar, bpchar) RETURNS bool AS '/usr1/proj/bray/sql/funcs.so' LANGUAGE 'c'; - -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> + + 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> |