<s>
PL/Perl	B-Language
(	O
Procedural	O
Language/Perl	O
)	O
is	O
a	O
procedural	O
language	O
supported	O
by	O
the	O
PostgreSQL	B-Application
RDBMS	O
.	O
</s>
<s>
PL/Perl	B-Language
,	O
as	O
an	O
imperative	B-Application
programming	I-Application
language	I-Application
,	O
allows	O
more	O
control	O
than	O
the	O
relational	B-Algorithm
algebra	I-Algorithm
of	O
SQL	B-Language
.	O
</s>
<s>
Programs	O
created	O
in	O
the	O
PL/Perl	B-Language
language	O
are	O
called	O
functions	O
and	O
can	O
use	O
most	O
of	O
the	O
features	O
that	O
the	O
Perl	B-Language
programming	I-Language
language	I-Language
provides	O
,	O
including	O
common	O
flow	O
control	O
structures	O
and	O
syntax	O
that	O
has	O
incorporated	O
regular	B-Language
expressions	I-Language
directly	O
.	O
</s>
<s>
These	O
functions	O
can	O
be	O
evaluated	O
as	O
part	O
of	O
a	O
SQL	B-Language
statement	O
,	O
or	O
in	O
response	O
to	O
a	O
trigger	B-Language
or	O
rule	O
.	O
</s>
<s>
The	O
design	O
goals	O
of	O
PL/Perl	B-Language
were	O
to	O
create	O
a	O
loadable	O
procedural	O
language	O
that	O
:	O
</s>
<s>
can	O
be	O
used	O
to	O
create	O
functions	O
and	O
trigger	B-Language
procedures	O
,	O
</s>
<s>
adds	O
control	O
structures	O
to	O
the	O
SQL	B-Language
language	I-Language
,	O
</s>
