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Minor doc patch: create function

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Gavin Sherry
This commit is contained in:
Bruce Momjian 2003-03-20 04:41:13 +00:00
parent ee303739d3
commit 7d1d7200a0
1 changed files with 30 additions and 22 deletions
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52
doc/src/sgml/ref/create_function.sgml
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@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_function.sgml,v 1.44 2003/01/19 00:13:29 momjian Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_function.sgml,v 1.45 2003/03/20 04:41:13 momjian Exp $
-->
<refentry id="SQL-CREATEFUNCTION">
@ -66,18 +66,22 @@ CREATE [ OR REPLACE ] FUNCTION <replaceable class="parameter">name</replaceable>
<listitem>
<para>
The data type(s) of the function's arguments, if any. The
input types may be base, complex, or domain types,
or the same as the type of an existing column.
The type of a column is referenced by writing <replaceable
class="parameter">tablename</replaceable>.<replaceable
class="parameter">columnname</replaceable><literal>%TYPE</literal>;
using this can sometimes help make a function independent from
changes to the definition of a table.
Depending on the implementation language it may also be allowed
to specify <quote>pseudo-types</> such as <type>cstring</>.
Pseudo-types indicate that the actual argument type is either
incompletely specified, or outside the set of ordinary SQL data types.
The data type(s) of the function's arguments (optionally
schema-qualified), if any. The input types may be base, complex, or
domain types, or the same as the type of an existing column.
</para>
<para>
The type of a column is referenced by writing <replaceable
class="parameter">tablename</replaceable>.<replaceable
class="parameter">columnname</replaceable><literal>%TYPE</literal>;
using this can sometimes help make a function independent from
changes to the definition of a table.
</para>
<para>
Depending on the implementation language it may also be allowed
to specify <quote>pseudo-types</> such as <type>cstring</>.
Pseudo-types indicate that the actual argument type is either
incompletely specified, or outside the set of ordinary SQL data types.
</para>
</listitem>
</varlistentry>
@ -87,9 +91,13 @@ CREATE [ OR REPLACE ] FUNCTION <replaceable class="parameter">name</replaceable>
<listitem>
<para>
The return data type. The return type may be specified as a
base, complex, or domain type, or the same as the type of an
existing column.
The return data type (optionally schema-qualified). The return type
may be specified as a base, complex, domain type
or the same as the type of an existing column. See the description
under <literal>argtype</literal> above on how to reference the type
of an existing column.
</para>
<para>
Depending on the implementation language it may also be allowed
to specify <quote>pseudo-types</> such as <type>cstring</>.
The <literal>setof</literal>
@ -432,13 +440,13 @@ CREATE FUNCTION point(complex) RETURNS point
<programlisting>
Point * complex_to_point (Complex *z)
{
Point *p;
Point *p;
p = (Point *) palloc(sizeof(Point));
p->x = z->x;
p->y = z->y;
return p;
p = (Point *) palloc(sizeof(Point));
p->x = z->x;
p->y = z->y;
return p;
}
</programlisting>