Index: doc/src/sgml/plperl.sgml
===================================================================
RCS file: /projects/cvsroot/pgsql/doc/src/sgml/plperl.sgml,v
retrieving revision 2.41
diff -c -r2.41 plperl.sgml
*** doc/src/sgml/plperl.sgml 5 Jun 2005 03:16:29 -0000 2.41
--- doc/src/sgml/plperl.sgml 12 Jul 2005 19:59:40 -0000
***************
*** 54,59 ****
--- 54,86 ----
The body of the function is ordinary Perl code.
+
+ As with ordinary Perl code, you should use the strict pragma,
+ which you can do one of two ways:
+
+
+
+
+ Globally, by turning on plperl (one of the you can use) and setting
+ plperl.use_strict to true in your postgresql.conf, or
+
+
+
+
+ One function at a time, by using PL/PerlU (you must be
+ database superuser to do this) and issuing a
+
+
+ use strict;
+
+
+ in the code.
+
+
+
+
The syntax of the CREATE FUNCTION command requires
***************
*** 118,123 ****
--- 145,165 ----
+ Perl can return PostgreSQL arrays as references to Perl arrays.
+ Here is an example:
+
+ CREATE OR REPLACE function returns_array()
+ RETURNS text[][]
+ LANGUAGE plperl
+ AS $$
+ return [['a"b','c,d'],['e\\f','g']];
+ $$;
+
+ select returns_array();
+
+
+
+
Composite-type arguments are passed to the function as references
to hashes. The keys of the hash are the attribute names of the
composite type. Here is an example:
***************
*** 158,171 ****
! PL/Perl functions can also return sets of either scalar or composite
! types. To do this, return a reference to an array that contains
! either scalars or references to hashes, respectively. Here are
! some simple examples:
CREATE OR REPLACE FUNCTION perl_set_int(int) RETURNS SETOF INTEGER AS $$
! return [0..$_[0]];
$$ LANGUAGE plperl;
SELECT * FROM perl_set_int(5);
--- 200,245 ----
! PL/Perl functions can also return sets of either scalar or
! composite types. In general, you'll want to return rows one at a
! time both to speed up startup time and to keep from queueing up
! the entire result set in memory. You can do this with
! return_next as illustrated below. Note that
! after the last return_next, you must put
! either return; or (better) return
! undef;
!
!
! CREATE OR REPLACE FUNCTION perl_set_int(int)
! RETURNS SETOF INTEGER
! LANGUAGE plperl AS $$
! foreach (0..$_[0]) {
! return_next($_);
! }
! return undef;
! $$;
!
! SELECT * FROM perl_set_int(5);
!
! CREATE OR REPLACE FUNCTION perl_set()
! RETURNS SETOF testrowperl
! LANGUAGE plperl AS $$
! return_next({f1 => 1, f2 => 'Hello', f3 => 'World' });
! return_next({ f1 => 2, f2 => 'Hello', f3 => 'PostgreSQL' });
! return_next({ f1 => 3, f2 => 'Hello', f3 => 'PL/Perl' });
! return undef;
! $$;
!
!
! For small result sets, you can return a reference to an array that
! contains either scalars, references to arrays, or references to
! hashes for simple types, array types, and composite types,
! respectively. Here are some simple examples of returning the entire
! result set as a reference:
CREATE OR REPLACE FUNCTION perl_set_int(int) RETURNS SETOF INTEGER AS $$
! return [0..$_[0]];
$$ LANGUAGE plperl;
SELECT * FROM perl_set_int(5);
***************
*** 182,192 ****
SELECT * FROM perl_set();
- When you do this, Perl will have to build the entire array in memory;
- therefore the technique does not scale to very large result sets. You
- can instead call return_next for each element of
- the result set, passing it either a scalar or a reference to a hash,
- as appropriate to your function's return type.
--- 256,261 ----
***************
*** 217,223 ****
! PL/Perl itself presently provides two additional Perl commands:
--- 286,292 ----
! PL/Perl itself presently provides four additional Perl commands:
***************
*** 228,233 ****
--- 297,306 ----
spi_exec_query(query [, max-rows])
spi_exec_query(command)
+ spi_query(query)
+ spi_fetchrow(result of spi_query)
+
+
Executes an SQL command. Here is an example of a query
***************
*** 280,287 ****
INSERT INTO test (i, v) VALUES (3, 'third line');
INSERT INTO test (i, v) VALUES (4, 'immortal');
! CREATE FUNCTION test_munge() RETURNS SETOF test AS $$
! my $res = [];
my $rv = spi_exec_query('select i, v from test;');
my $status = $rv->{status};
my $nrows = $rv->{processed};
--- 353,361 ----
INSERT INTO test (i, v) VALUES (3, 'third line');
INSERT INTO test (i, v) VALUES (4, 'immortal');
! CREATE FUNCTION test_munge()
! RETURNS SETOF
! test LANGUAGE plperl AS $$
my $rv = spi_exec_query('select i, v from test;');
my $status = $rv->{status};
my $nrows = $rv->{processed};
***************
*** 289,298 ****
my $row = $rv->{rows}[$rn];
$row->{i} += 200 if defined($row->{i});
$row->{v} =~ tr/A-Za-z/a-zA-Z/ if (defined($row->{v}));
! push @$res, $row;
}
! return $res;
! $$ LANGUAGE plperl;
SELECT * FROM test_munge();
--- 363,372 ----
my $row = $rv->{rows}[$rn];
$row->{i} += 200 if defined($row->{i});
$row->{v} =~ tr/A-Za-z/a-zA-Z/ if (defined($row->{v}));
! return_next($row);
}
! return undef;
! $$;
SELECT * FROM test_munge();
Index: doc/src/sgml/runtime.sgml
===================================================================
RCS file: /projects/cvsroot/pgsql/doc/src/sgml/runtime.sgml,v
retrieving revision 1.337
diff -c -r1.337 runtime.sgml
*** doc/src/sgml/runtime.sgml 6 Jul 2005 14:45:12 -0000 1.337
--- doc/src/sgml/runtime.sgml 12 Jul 2005 19:59:45 -0000
***************
*** 4103,4111 ****
when using custom variables:
! custom_variable_classes = 'plr,pljava'
plr.path = '/usr/lib/R'
pljava.foo = 1
plruby.bar = true # generates error, unknown class name
--- 4103,4112 ----
when using custom variables:
! custom_variable_classes = 'plperl,plr,pljava'
plr.path = '/usr/lib/R'
pljava.foo = 1
+ plperl.use_strict = true # now without having to use pl/perlU! :)
plruby.bar = true # generates error, unknown class name