diff options
Diffstat (limited to 'doc/src/sgml/ref/create_function.sgml')
| -rw-r--r-- | doc/src/sgml/ref/create_function.sgml | 25 |
1 files changed, 12 insertions, 13 deletions
diff --git a/doc/src/sgml/ref/create_function.sgml b/doc/src/sgml/ref/create_function.sgml index 2c618140c85..105a4a16103 100644 --- a/doc/src/sgml/ref/create_function.sgml +++ b/doc/src/sgml/ref/create_function.sgml @@ -1,5 +1,5 @@ <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_function.sgml,v 1.41 2002/07/24 19:11:07 petere Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_function.sgml,v 1.42 2002/08/22 00:01:40 tgl Exp $ --> <refentry id="SQL-CREATEFUNCTION"> @@ -67,16 +67,17 @@ 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 or complex types, - <literal>opaque</literal>, or the same as the type of an - existing column. <literal>Opaque</literal> indicates - that the function accepts arguments of a non-SQL type such as - <type>char *</type>. - The type of a column is indicated using <replaceable + 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 datatypes. </para> </listitem> </varlistentry> @@ -87,15 +88,13 @@ CREATE [ OR REPLACE ] FUNCTION <replaceable class="parameter">name</replaceable> <listitem> <para> The return data type. The return type may be specified as a - base type, complex type, <literal>setof</literal> type, - <literal>opaque</literal>, or the same as the type of an + base, complex, or domain type, or the same as the type of an existing column. + Depending on the implementation language it may also be allowed + to specify <quote>pseudo-types</> such as <type>cstring</>. The <literal>setof</literal> modifier indicates that the function will return a set of - items, rather than a single item. Functions with a declared - return type of <literal>opaque</literal> do not return a value. - These cannot be called directly; trigger functions make use of - this feature. + items, rather than a single item. </para> </listitem> </varlistentry> |