<!--

$Header: /cvsroot/pgsql/doc/src/sgml/Attic/plsql.sgml,v 2.8 2000/05/17 00:15:48 momjian Exp $

$Header: /cvsroot/pgsql/doc/src/sgml/Attic/plsql.sgml,v 2.9 2000/08/2515:17:36 thomas Exp $

-->

<chapter>

<varlistentry>

<term>

<replaceable>name</replaceable> [ CONSTANT ]

<replaceable>type</replaceable>> [ NOT NULL ] [ DEFAULT | :=

<replaceable>type</replaceable> [ NOT NULL ] [ DEFAULT | :=

<replaceable>value</replaceable> ];

</term>

<listitem>

<!--

$Header: /cvsroot/pgsql/doc/src/sgml/pltcl.sgml,v 2.4 2000/05/18 14:24:32 momjian Exp $

$Header: /cvsroot/pgsql/doc/src/sgml/pltcl.sgml,v 2.5 2000/08/25 15:17:36 thomas Exp $

-->

<chapter>

return [array get NEW]

' LANGUAGE 'pltcl';

CREATE TABLE mytab (num int4, modcnt int4,desc text);

CREATE TABLE mytab (num int4, modcnt int4,description text);

CREATE TRIGGER trig_mytab_modcount BEFORE INSERT OR UPDATE ON mytab

FOR EACH ROW EXECUTE PROCEDURE trigfunc_modcount('modcnt');

will print a DEBUG log message for every row of pg_class. The return value

of <function>spi_exec</function> is the number of rows

affected by query as found in

affected bythequery as found in

the global variable SPI_processed.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term>spi_exec ?-count <replaceable>n</replaceable>? ?-array<replaceable>name</replaceable>? ?-nulls<replaceable>string</replaceable>? <replaceable>query</replaceable> ?<replaceable>value-list</replaceable>? ?<replaceable>loop-body</replaceable>?</term>

<term>spi_exec ?-count <replaceable>n</replaceable>? ?-array<replaceable>name</replaceable>? ?-nulls<replaceable>string</replaceable>? <replaceable>queryid</replaceable> ?<replaceable>value-list</replaceable>? ?<replaceable>loop-body</replaceable>?</term>

<listitem>

<para>

Execute a prepared plan from spi_prepare with variable substitution.

<!--

$Header: /cvsroot/pgsql/doc/src/sgml/postgres.sgml,v 1.39 2000/07/21 00:44:13 petere Exp $

$Header: /cvsroot/pgsql/doc/src/sgml/postgres.sgml,v 1.40 2000/08/25 15:17:37 thomas Exp $

-->

<!doctypebook PUBLIC "-//OASIS//DTD DocBook V3.1//EN" [

<!doctypeset PUBLIC "-//OASIS//DTD DocBook V3.1//EN" [

<!entity version "7.1">

<!entity majorversion "7.1">

]>

<!-- entity manpages SYSTEM "man/manpages.sgml" subdoc -->

<book id="postgres">

<set id="postgres">

<title>PostgreSQL Documentation</title>

<!-- Title information -->

<title>PostgreSQL</title>

<bookinfo>

<releaseinfo>Covering v7.0 for general release</releaseinfo>

<bookbiblio>

<authorgroup>

<corpauthor>The PostgreSQL Development Team</corpauthor>

</authorgroup>

<!-- editor in authorgroup is not supported

<AuthorGroup>

-->

<editor>

<firstname>Thomas</firstname>

<surname>Lockhart</surname>

<affiliation>

<orgname>Caltech/JPL</orgname>

</affiliation>

</editor>

<!--

</AuthorGroup>

-->

<!--

<AuthorInitials>TGL</AuthorInitials>

-->

<date>(last updated 2000-05-01)</date>

</bookbiblio>

<legalnotice>

<para>

<productname>PostgreSQL</productname> is Copyright &copy; 1996-2000

by PostgreSQL Inc.

</para>

</legalnotice>

</bookinfo>

<!--

<TOC> </TOC>

<LOT> </LOT>

-->

<!--

<Dedication>

<Para>

Your name here...

</Para>

</Dedication>

-->

<preface id="preface">

<title>Summary</title>

<para>

<productname>Postgres</productname>,

developed originally in the UC Berkeley Computer Science Department,

pioneered many of the object-relational concepts

now becoming available in some commercial databases.

It provides SQL92/SQL3 language support,

transaction integrity, and type extensibility.

<productname>PostgreSQL</productname> is an

open-source descendant of this original Berkeley code.

</para>

</preface>

<part id="part-user">

<book id="user">

<title>User's Guide</title>

<partintro>

<para>

Information for users.

</para>

</partintro>

<bookinfo>

<abstract>

<para>

Information for Users

</para>

</abstract>

</bookinfo>

&intro;

&syntax;

&plan;

&populate;

&commands;

</part>

<part id="part-admin">

&datetime;

<!--

&contacts;

-->

&biblio;

</book>

<book id="admin">

<title>Administrator's Guide</title>

<partintro>

<para>

Installation and maintenance information.

</para>

</partintro>

<bookinfo>

<abstract>

<para>

Information for Administrators

</para>

</abstract>

</bookinfo>

<!--

Disable these extra intro chapters since some elements (e.g. y2k

statement) are included in the first intro.sgml and cause errors if

&recovery;

&regress;

&release;

</part>

</book>

<part id="part-programmer">

<book id="programmer">

<title>Programmer's Guide</title>

<partintro>

<para>

Information for extending <productname>Postgres</productname>.

</para>

</partintro>

<bookinfo>

<abstract>

<para>

Information on extending Postgres

</para>

</abstract>

</bookinfo>

<!--

Disable these extra intro chapters since some elements (e.g. y2k

statement) are included in the first intro.sgml and cause errors if

&trigger;

&spi;

&xplang;

</part>

</book>

<part id="part-interfaces">

<book id="interfaces">

<title>Interfaces</title>

<partintro>

<para>

User and programmer interfaces.

</para>

</partintro>

<bookinfo>

<abstract>

<para>

Information on Postgres language interfaces

</para>

</abstract>

</bookinfo>

&func-ref;

&lobj;

&ecpg;

&odbc;

&jdbc;

&lisp;

</part>

</book>

<part id="part-developer">

<book id="developer">

<title>Developer's Guide</title>

<partintro>

<para>

The Developer's Guide includes discussion of design decisions and

suggestions for future development.

</para>

</partintro>

<bookinfo>

<abstract>

<para>

Information for Postgres developers

</>

</>

</bookinfo>

&sources;

&arch-dev;

&geqo;

&compiler;

&bki;

&page;

</part>

&cvs;

&docguide;

</book>

<part id="part-tutorial">

<book id="tutorial">

<title>Tutorial</title>

<partintro>

<para>

Introduction for new users.

</para>

</partintro>

&sql;

&arch;

&start;

&query;

&advanced;

</part>

</book>

<part id="part-appendix">

<title>Appendices</title>

<partintro>

<para>

Additional related information.

</para>

</partintro>

&datetime;

&cvs;

&docguide;

<!--

&contacts;

-->

&biblio;

</part>

<!--

Omit index until we have some index entries.

</index>

-->

</book>

</set>

<!-- Keep this comment at the end of the file

Local variables:

<!--

$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_function.sgml,v 1.16 2000/08/24 23:36:29 tgl Exp $

$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_function.sgml,v 1.17 2000/08/25 15:17:50 thomas Exp $

Postgres documentation

-->

<para>

The return data type.

The output type may be specified as a base type, complex type,

<literal>setof <replaceable class="parameter">type</replaceable></literal>,

or <literal>opaque</literal>.

The <literal>setof</literal>

<option>setof <replaceable class="parameter">type</replaceable></option>,

or <option>opaque</option>.

The <option>setof</option>

modifier indicates that the function will return a set of items,

rather than a single item.

</para>

<variablelist>

<varlistentry>

<literal>iscachable</literal>

<term>iscachable</term>

<listitem>

<para>

<literal>iscachable</literal> indicates that the function always

<option>iscachable</option> indicates that the function always

returns the same result when given the same argument values (i.e.,

it does not do database lookups or otherwise use information not

directly present in its parameter list). The optimizer uses

<literal>iscachable</literal> to know whether it is safe to

<option>iscachable</option> to know whether it is safe to

pre-evaluate a call of the function.

</para>

</listitem>

</varlistentry>

<varlistentry>

<literal>isstrict</literal>

<term>isstrict</term>

<listitem>

<para>

<literal>isstrict</literal> indicates that the function always

<option>isstrict</option> indicates that the function always

returns NULL whenever any of its arguments are NULL. If this

attribute is specified, the function is not executed when there

are NULL arguments; instead a NULL result is assumed automatically.

When <literal>isstrict</literal> is not specified, the function will

When <option>isstrict</option> is not specified, the function will

be called for NULL inputs. It is then the function author's

responsibility to check for NULLs if necessary and respond

appropriately.