<para>

PL/Perl is a loadable procedural language that enables you to write

<productname>PostgreSQL</productname> functions in the

<productname>PostgreSQL</productname> functionsand proceduresin the

<ulink url="https://www.perl.org">Perl programming language</ulink>.

</para>

<para>

The main advantage to using PL/Perl is that this allows use,

within stored functions, of the manyfold <quote>string

within stored functions and procedures, of the manyfold <quote>string

munging</quote> operators and functions available for Perl. Parsing

complex strings might be easier using Perl than it is with the

string functions and control structures provided in PL/pgSQL.

<itemizedlist>

<listitem>

<para>

can be used to create functions and triggers,

can be used to create functions, procedures, and triggers,

</para>

</listitem>

<listitem>

</listitem>

<listitem>

<para>

inherits all user-defined types, functions, and operators,

inherits all user-defined types, functions,procedures,and operators,

</para>

</listitem>

<listitem>

<para>

The <application>PL/Python</application> procedural language allows

<productname>PostgreSQL</productname> functions to be written in the

<productname>PostgreSQL</productname> functionsand proceduresto be written in the

<ulink url="https://www.python.org">Python language</ulink>.

</para>

<productname>PostgreSQL</productname> database system

that enables the <ulink url="https://www.tcl.tk/">

Tcl language</ulink> to be used to write

<productname>PostgreSQL</productname> functions.

<productname>PostgreSQL</productname> functions and procedures.

</para>

<!-- **** PL/Tcl overview **** -->

The <firstterm>Server Programming Interface</firstterm>

(<acronym>SPI</acronym>) gives writers of user-defined

<acronym>C</acronym> functions the ability to run

<acronym>SQL</acronym> commands inside their functions.

<acronym>SQL</acronym> commands inside their functions or procedures.

<acronym>SPI</acronym> is a set of

interface functions to simplify access to the parser, planner,

and executor. <acronym>SPI</acronym> also does some