~ubuntu-branches/ubuntu/oneiric/postgresql-9.1/oneiric-security

--
-- Test result value processing
--
CREATE OR REPLACE FUNCTION perl_int(int) RETURNS INTEGER AS $$
return undef;
$$ LANGUAGE plperl;
SELECT perl_int(11);
 perl_int 
----------
         
(1 row)

SELECT * FROM perl_int(42);
 perl_int 
----------
         
(1 row)

CREATE OR REPLACE FUNCTION perl_int(int) RETURNS INTEGER AS $$
return $_[0] + 1;
$$ LANGUAGE plperl;
SELECT perl_int(11);
 perl_int 
----------
       12
(1 row)

SELECT * FROM perl_int(42);
 perl_int 
----------
       43
(1 row)

CREATE OR REPLACE FUNCTION perl_set_int(int) RETURNS SETOF INTEGER AS $$
return undef;
$$ LANGUAGE plperl;
SELECT perl_set_int(5);
 perl_set_int 
--------------
(0 rows)

SELECT * FROM perl_set_int(5);
 perl_set_int 
--------------
(0 rows)

CREATE OR REPLACE FUNCTION perl_set_int(int) RETURNS SETOF INTEGER AS $$
return [0..$_[0]];
$$ LANGUAGE plperl;
SELECT perl_set_int(5);
 perl_set_int 
--------------
            0
            1
            2
            3
            4
            5
(6 rows)

SELECT * FROM perl_set_int(5);
 perl_set_int 
--------------
            0
            1
            2
            3
            4
            5
(6 rows)

CREATE TYPE testnestperl AS (f5 integer[]);
CREATE TYPE testrowperl AS (f1 integer, f2 text, f3 text, f4 testnestperl);
CREATE OR REPLACE FUNCTION perl_row() RETURNS testrowperl AS $$
    return undef;
$$ LANGUAGE plperl;
SELECT perl_row();
 perl_row 
----------
 
(1 row)

SELECT * FROM perl_row();
 f1 | f2 | f3 | f4 
----+----+----+----
    |    |    | 
(1 row)

CREATE OR REPLACE FUNCTION perl_row() RETURNS testrowperl AS $$
    return {f2 => 'hello', f1 => 1, f3 => 'world', 'f4' => { 'f5' => [[1]] } };
$$ LANGUAGE plperl;
SELECT perl_row();
         perl_row          
---------------------------
 (1,hello,world,"({{1}})")
(1 row)

SELECT * FROM perl_row();
 f1 |  f2   |  f3   |   f4    
----+-------+-------+---------
  1 | hello | world | ({{1}})
(1 row)

-- test returning a composite literal
CREATE OR REPLACE FUNCTION perl_row_lit() RETURNS testrowperl AS $$
    return '(1,hello,world,"({{1}})")';
$$ LANGUAGE plperl;
SELECT perl_row_lit();
       perl_row_lit        
---------------------------
 (1,hello,world,"({{1}})")
(1 row)

CREATE OR REPLACE FUNCTION perl_set() RETURNS SETOF testrowperl AS $$
    return undef;
$$  LANGUAGE plperl;
SELECT perl_set();
 perl_set 
----------
(0 rows)

SELECT * FROM perl_set();
 f1 | f2 | f3 | f4 
----+----+----+----
(0 rows)

CREATE OR REPLACE FUNCTION perl_set() RETURNS SETOF testrowperl AS $$
    return [
        { f1 => 1, f2 => 'Hello', f3 =>  'World' },
        undef,
        { f1 => 3, f2 => 'Hello', f3 =>  'PL/Perl', 'f4' => {} },
        { f1 => 4, f2 => 'Hello', f3 =>  'PL/Perl', 'f4' => { 'f5' => undef }},
        { f1 => 5, f2 => 'Hello', f3 =>  'PL/Perl', 'f4' => { 'f5' => '{1}' }},
        { f1 => 6, f2 => 'Hello', f3 =>  'PL/Perl', 'f4' => { 'f5' => [1] }},
    ];
$$  LANGUAGE plperl;
SELECT perl_set();
ERROR:  SETOF-composite-returning PL/Perl function must call return_next with reference to hash
CONTEXT:  PL/Perl function "perl_set"
SELECT * FROM perl_set();
ERROR:  SETOF-composite-returning PL/Perl function must call return_next with reference to hash
CONTEXT:  PL/Perl function "perl_set"
CREATE OR REPLACE FUNCTION perl_set() RETURNS SETOF testrowperl AS $$
    return [
        { f1 => 1, f2 => 'Hello', f3 =>  'World' },
        { f1 => 2, f2 => 'Hello', f3 =>  'PostgreSQL', 'f4' => undef },
        { f1 => 3, f2 => 'Hello', f3 =>  'PL/Perl', 'f4' => {} },
        { f1 => 4, f2 => 'Hello', f3 =>  'PL/Perl', 'f4' => { 'f5' => undef }},
        { f1 => 5, f2 => 'Hello', f3 =>  'PL/Perl', 'f4' => { 'f5' => '{1}' }},
        { f1 => 6, f2 => 'Hello', f3 =>  'PL/Perl', 'f4' => { 'f5' => [1] }},
        { f1 => 7, f2 => 'Hello', f3 =>  'PL/Perl', 'f4' => '({1})' },
    ];
$$  LANGUAGE plperl;
SELECT perl_set();
         perl_set          
---------------------------
 (1,Hello,World,)
 (2,Hello,PostgreSQL,)
 (3,Hello,PL/Perl,"()")
 (4,Hello,PL/Perl,"()")
 (5,Hello,PL/Perl,"({1})")
 (6,Hello,PL/Perl,"({1})")
 (7,Hello,PL/Perl,"({1})")
(7 rows)

SELECT * FROM perl_set();
 f1 |  f2   |     f3     |  f4   
----+-------+------------+-------
  1 | Hello | World      | 
  2 | Hello | PostgreSQL | 
  3 | Hello | PL/Perl    | ()
  4 | Hello | PL/Perl    | ()
  5 | Hello | PL/Perl    | ({1})
  6 | Hello | PL/Perl    | ({1})
  7 | Hello | PL/Perl    | ({1})
(7 rows)

CREATE OR REPLACE FUNCTION perl_record() RETURNS record AS $$
    return undef;
$$ LANGUAGE plperl;
SELECT perl_record();
 perl_record 
-------------
 
(1 row)

SELECT * FROM perl_record();
ERROR:  a column definition list is required for functions returning "record"
LINE 1: SELECT * FROM perl_record();
                      ^
SELECT * FROM perl_record() AS (f1 integer, f2 text, f3 text, f4 testnestperl);
 f1 | f2 | f3 | f4 
----+----+----+----
    |    |    | 
(1 row)

CREATE OR REPLACE FUNCTION perl_record() RETURNS record AS $$
    return {f2 => 'hello', f1 => 1, f3 => 'world', 'f4' => { 'f5' => [1] } };
$$ LANGUAGE plperl;
SELECT perl_record();
ERROR:  function returning record called in context that cannot accept type record
CONTEXT:  PL/Perl function "perl_record"
SELECT * FROM perl_record();
ERROR:  a column definition list is required for functions returning "record"
LINE 1: SELECT * FROM perl_record();
                      ^
SELECT * FROM perl_record() AS (f1 integer, f2 text, f3 text, f4 testnestperl);
 f1 |  f2   |  f3   |  f4   
----+-------+-------+-------
  1 | hello | world | ({1})
(1 row)

CREATE OR REPLACE FUNCTION perl_record_set() RETURNS SETOF record AS $$
    return undef;
$$  LANGUAGE plperl;
SELECT perl_record_set();
ERROR:  set-valued function called in context that cannot accept a set
CONTEXT:  PL/Perl function "perl_record_set"
SELECT * FROM perl_record_set();
ERROR:  a column definition list is required for functions returning "record"
LINE 1: SELECT * FROM perl_record_set();
                      ^
SELECT * FROM perl_record_set() AS (f1 integer, f2 text, f3 text);
 f1 | f2 | f3 
----+----+----
(0 rows)

CREATE OR REPLACE FUNCTION perl_record_set() RETURNS SETOF record AS $$
    return [
        { f1 => 1, f2 => 'Hello', f3 =>  'World' },
        undef,
        { f1 => 3, f2 => 'Hello', f3 =>  'PL/Perl' }
    ];
$$  LANGUAGE plperl;
SELECT perl_record_set();
ERROR:  set-valued function called in context that cannot accept a set
CONTEXT:  PL/Perl function "perl_record_set"
SELECT * FROM perl_record_set();
ERROR:  a column definition list is required for functions returning "record"
LINE 1: SELECT * FROM perl_record_set();
                      ^
SELECT * FROM perl_record_set() AS (f1 integer, f2 text, f3 text);
ERROR:  SETOF-composite-returning PL/Perl function must call return_next with reference to hash
CONTEXT:  PL/Perl function "perl_record_set"
CREATE OR REPLACE FUNCTION perl_record_set() RETURNS SETOF record AS $$
    return [
        { f1 => 1, f2 => 'Hello', f3 =>  'World' },
        { f1 => 2, f2 => 'Hello', f3 =>  'PostgreSQL' },
        { f1 => 3, f2 => 'Hello', f3 =>  'PL/Perl' }
    ];
$$  LANGUAGE plperl;
SELECT perl_record_set();
ERROR:  set-valued function called in context that cannot accept a set
CONTEXT:  PL/Perl function "perl_record_set"
SELECT * FROM perl_record_set();
ERROR:  a column definition list is required for functions returning "record"
LINE 1: SELECT * FROM perl_record_set();
                      ^
SELECT * FROM perl_record_set() AS (f1 integer, f2 text, f3 text);
 f1 |  f2   |     f3     
----+-------+------------
  1 | Hello | World
  2 | Hello | PostgreSQL
  3 | Hello | PL/Perl
(3 rows)

CREATE OR REPLACE FUNCTION
perl_out_params(f1 out integer, f2 out text, f3 out text) AS $$
    return {f2 => 'hello', f1 => 1, f3 => 'world'};
$$ LANGUAGE plperl;
SELECT perl_out_params();
 perl_out_params 
-----------------
 (1,hello,world)
(1 row)

SELECT * FROM perl_out_params();
 f1 |  f2   |  f3   
----+-------+-------
  1 | hello | world
(1 row)

SELECT (perl_out_params()).f2;
  f2   
-------
 hello
(1 row)

CREATE OR REPLACE FUNCTION
perl_out_params_set(out f1 integer, out f2 text, out f3 text)
RETURNS SETOF record AS $$
    return [
        { f1 => 1, f2 => 'Hello', f3 =>  'World' },
        { f1 => 2, f2 => 'Hello', f3 =>  'PostgreSQL' },
        { f1 => 3, f2 => 'Hello', f3 =>  'PL/Perl' }
    ];
$$  LANGUAGE plperl;
SELECT perl_out_params_set();
 perl_out_params_set  
----------------------
 (1,Hello,World)
 (2,Hello,PostgreSQL)
 (3,Hello,PL/Perl)
(3 rows)

SELECT * FROM perl_out_params_set();
 f1 |  f2   |     f3     
----+-------+------------
  1 | Hello | World
  2 | Hello | PostgreSQL
  3 | Hello | PL/Perl
(3 rows)

SELECT (perl_out_params_set()).f3;
     f3     
------------
 World
 PostgreSQL
 PL/Perl
(3 rows)

--
-- Check behavior with erroneous return values
--
CREATE TYPE footype AS (x INTEGER, y INTEGER);
CREATE OR REPLACE FUNCTION foo_good() RETURNS SETOF footype AS $$
return [
    {x => 1, y => 2},
    {x => 3, y => 4}
];
$$ LANGUAGE plperl;
SELECT * FROM foo_good();
 x | y 
---+---
 1 | 2
 3 | 4
(2 rows)

CREATE OR REPLACE FUNCTION foo_bad() RETURNS footype AS $$
    return {y => 3, z => 4};
$$ LANGUAGE plperl;
SELECT * FROM foo_bad();
ERROR:  Perl hash contains nonexistent column "z"
CONTEXT:  PL/Perl function "foo_bad"
CREATE OR REPLACE FUNCTION foo_bad() RETURNS footype AS $$
return 42;
$$ LANGUAGE plperl;
SELECT * FROM foo_bad();
ERROR:  malformed record literal: "42"
DETAIL:  Missing left parenthesis.
CONTEXT:  PL/Perl function "foo_bad"
CREATE OR REPLACE FUNCTION foo_bad() RETURNS footype AS $$
return [
    [1, 2],
    [3, 4]
];
$$ LANGUAGE plperl;
SELECT * FROM foo_bad();
ERROR:  cannot convert Perl array to non-array type footype
CONTEXT:  PL/Perl function "foo_bad"
CREATE OR REPLACE FUNCTION foo_set_bad() RETURNS SETOF footype AS $$
    return 42;
$$ LANGUAGE plperl;
SELECT * FROM foo_set_bad();
ERROR:  set-returning PL/Perl function must return reference to array or use return_next
CONTEXT:  PL/Perl function "foo_set_bad"
CREATE OR REPLACE FUNCTION foo_set_bad() RETURNS SETOF footype AS $$
    return {y => 3, z => 4};
$$ LANGUAGE plperl;
SELECT * FROM foo_set_bad();
ERROR:  set-returning PL/Perl function must return reference to array or use return_next
CONTEXT:  PL/Perl function "foo_set_bad"
CREATE OR REPLACE FUNCTION foo_set_bad() RETURNS SETOF footype AS $$
return [
    [1, 2],
    [3, 4]
];
$$ LANGUAGE plperl;
SELECT * FROM foo_set_bad();
ERROR:  SETOF-composite-returning PL/Perl function must call return_next with reference to hash
CONTEXT:  PL/Perl function "foo_set_bad"
CREATE OR REPLACE FUNCTION foo_set_bad() RETURNS SETOF footype AS $$
return [
    {y => 3, z => 4}
];
$$ LANGUAGE plperl;
SELECT * FROM foo_set_bad();
ERROR:  Perl hash contains nonexistent column "z"
CONTEXT:  PL/Perl function "foo_set_bad"
--
-- Check passing a tuple argument
--
CREATE OR REPLACE FUNCTION perl_get_field(footype, text) RETURNS integer AS $$
    return $_[0]->{$_[1]};
$$ LANGUAGE plperl;
SELECT perl_get_field((11,12), 'x');
 perl_get_field 
----------------
             11
(1 row)

SELECT perl_get_field((11,12), 'y');
 perl_get_field 
----------------
             12
(1 row)

SELECT perl_get_field((11,12), 'z');
 perl_get_field 
----------------
               
(1 row)

--
-- Test return_next
--
CREATE OR REPLACE FUNCTION perl_srf_rn() RETURNS SETOF RECORD AS $$
my $i = 0;
for ("World", "PostgreSQL", "PL/Perl") {
    return_next({f1=>++$i, f2=>'Hello', f3=>$_});
}
return;
$$ language plperl;
SELECT * from perl_srf_rn() AS (f1 INTEGER, f2 TEXT, f3 TEXT);
 f1 |  f2   |     f3     
----+-------+------------
  1 | Hello | World
  2 | Hello | PostgreSQL
  3 | Hello | PL/Perl
(3 rows)

--
-- Test spi_query/spi_fetchrow
--
CREATE OR REPLACE FUNCTION perl_spi_func() RETURNS SETOF INTEGER AS $$
my $x = spi_query("select 1 as a union select 2 as a");
while (defined (my $y = spi_fetchrow($x))) {
    return_next($y->{a});
}
return;
$$ LANGUAGE plperl;
SELECT * from perl_spi_func();
 perl_spi_func 
---------------
             1
             2
(2 rows)

--
-- Test spi_fetchrow abort
--
CREATE OR REPLACE FUNCTION perl_spi_func2() RETURNS INTEGER AS $$
my $x = spi_query("select 1 as a union select 2 as a");
spi_cursor_close( $x);
return 0;
$$ LANGUAGE plperl;
SELECT * from perl_spi_func2();
 perl_spi_func2 
----------------
              0
(1 row)

---
--- Test recursion via SPI
---
CREATE OR REPLACE FUNCTION recurse(i int) RETURNS SETOF TEXT LANGUAGE plperl
AS $$

  my $i = shift;
  foreach my $x (1..$i)
  {
    return_next "hello $x";
  }
  if ($i > 2)
  {
    my $z = $i-1;
    my $cursor = spi_query("select * from recurse($z)");
    while (defined(my $row = spi_fetchrow($cursor)))
    {
      return_next "recurse $i: $row->{recurse}";
    }
  }
  return undef;

$$;
SELECT * FROM recurse(2);
 recurse 
---------
 hello 1
 hello 2
(2 rows)

SELECT * FROM recurse(3);
      recurse       
--------------------
 hello 1
 hello 2
 hello 3
 recurse 3: hello 1
 recurse 3: hello 2
(5 rows)

---
--- Test array return
---
CREATE OR REPLACE FUNCTION  array_of_text() RETURNS TEXT[][]
LANGUAGE plperl as $$
    return [['a"b',undef,'c,d'],['e\\f',undef,'g']];
$$;
SELECT array_of_text();
             array_of_text             
---------------------------------------
 {{"a\"b",NULL,"c,d"},{"e\\f",NULL,g}}
(1 row)

--
-- Test spi_prepare/spi_exec_prepared/spi_freeplan
--
CREATE OR REPLACE FUNCTION perl_spi_prepared(INTEGER) RETURNS INTEGER AS $$
   my $x = spi_prepare('select $1 AS a', 'INTEGER');
   my $q = spi_exec_prepared( $x, $_[0] + 1);
   spi_freeplan($x);
return $q->{rows}->[0]->{a};
$$ LANGUAGE plperl;
SELECT * from perl_spi_prepared(42);
 perl_spi_prepared 
-------------------
                43
(1 row)

--
-- Test spi_prepare/spi_query_prepared/spi_freeplan
--
CREATE OR REPLACE FUNCTION perl_spi_prepared_set(INTEGER, INTEGER) RETURNS SETOF INTEGER AS $$
  my $x = spi_prepare('SELECT $1 AS a union select $2 as a', 'INT4', 'INT4');
  my $q = spi_query_prepared( $x, 1+$_[0], 2+$_[1]);
  while (defined (my $y = spi_fetchrow($q))) {
      return_next $y->{a};
  }
  spi_freeplan($x);
  return;
$$ LANGUAGE plperl;
SELECT * from perl_spi_prepared_set(1,2);
 perl_spi_prepared_set 
-----------------------
                     2
                     4
(2 rows)

--
-- Test prepare with a type with spaces
--
CREATE OR REPLACE FUNCTION perl_spi_prepared_double(double precision) RETURNS double precision AS $$
  my $x = spi_prepare('SELECT 10.0 * $1 AS a', 'DOUBLE PRECISION');
  my $q = spi_query_prepared($x,$_[0]);
  my $result;
  while (defined (my $y = spi_fetchrow($q))) {
      $result = $y->{a};
  }
  spi_freeplan($x);
  return $result;
$$ LANGUAGE plperl;
SELECT perl_spi_prepared_double(4.35) as "double precision";
 double precision 
------------------
             43.5
(1 row)

--
-- Test with a bad type
--
CREATE OR REPLACE FUNCTION perl_spi_prepared_bad(double precision) RETURNS double precision AS $$
  my $x = spi_prepare('SELECT 10.0 * $1 AS a', 'does_not_exist');
  my $q = spi_query_prepared($x,$_[0]);
  my $result;
  while (defined (my $y = spi_fetchrow($q))) {
      $result = $y->{a};
  }
  spi_freeplan($x);
  return $result;
$$ LANGUAGE plperl;
SELECT perl_spi_prepared_bad(4.35) as "double precision";
ERROR:  type "does_not_exist" does not exist at line 2.
CONTEXT:  PL/Perl function "perl_spi_prepared_bad"
-- Test with a row type
CREATE OR REPLACE FUNCTION perl_spi_prepared() RETURNS INTEGER AS $$
   my $x = spi_prepare('select $1::footype AS a', 'footype');
   my $q = spi_exec_prepared( $x, '(1, 2)');
   spi_freeplan($x);
return $q->{rows}->[0]->{a}->{x};
$$ LANGUAGE plperl;
SELECT * from perl_spi_prepared();
 perl_spi_prepared 
-------------------
                 1
(1 row)

CREATE OR REPLACE FUNCTION perl_spi_prepared_row(footype) RETURNS footype AS $$
   my $footype = shift;
   my $x = spi_prepare('select $1 AS a', 'footype');
   my $q = spi_exec_prepared( $x, {}, $footype );
   spi_freeplan($x);
return $q->{rows}->[0]->{a};
$$ LANGUAGE plperl;
SELECT * from perl_spi_prepared_row('(1, 2)');
 x | y 
---+---
 1 | 2
(1 row)

-- simple test of a DO block
DO $$
  $a = 'This is a test';
  elog(NOTICE, $a);
$$ LANGUAGE plperl;
NOTICE:  This is a test
CONTEXT:  PL/Perl anonymous code block
-- check that restricted operations are rejected in a plperl DO block
DO $$ system("/nonesuch"); $$ LANGUAGE plperl;
ERROR:  'system' trapped by operation mask at line 1.
CONTEXT:  PL/Perl anonymous code block
DO $$ qx("/nonesuch"); $$ LANGUAGE plperl;
ERROR:  'quoted execution (``, qx)' trapped by operation mask at line 1.
CONTEXT:  PL/Perl anonymous code block
DO $$ open my $fh, "</nonesuch"; $$ LANGUAGE plperl;
ERROR:  'open' trapped by operation mask at line 1.
CONTEXT:  PL/Perl anonymous code block
-- check that eval is allowed and eval'd restricted ops are caught
DO $$ eval q{chdir '.'}; warn "Caught: $@"; $$ LANGUAGE plperl;
WARNING:  Caught: 'chdir' trapped by operation mask at line 2.
CONTEXT:  PL/Perl anonymous code block
-- check that compiling do (dofile opcode) is allowed
-- but that executing it for a file not already loaded (via require) dies
DO $$ warn do "/dev/null"; $$ LANGUAGE plperl;
ERROR:  Unable to load /dev/null into plperl at line 1.
CONTEXT:  PL/Perl anonymous code block
-- check that we can't "use" a module that's not been loaded already
-- compile-time error: "Unable to load blib.pm into plperl"
DO $$ use blib; $$ LANGUAGE plperl;
ERROR:  Unable to load blib.pm into plperl at line 1.
BEGIN failed--compilation aborted at line 1.
CONTEXT:  PL/Perl anonymous code block
-- check that we can "use" a module that has already been loaded
-- runtime error: "Can't use string ("foo") as a SCALAR ref while "strict refs" in use
DO $do$ use strict; my $name = "foo"; my $ref = $$name; $do$ LANGUAGE plperl;
ERROR:  Can't use string ("foo") as a SCALAR ref while "strict refs" in use at line 1.
CONTEXT:  PL/Perl anonymous code block
-- check that we can "use warnings" (in this case to turn a warn into an error)
-- yields "ERROR:  Useless use of sort in scalar context."
DO $do$ use warnings FATAL => qw(void) ; my @y; my $x = sort @y; 1; $do$ LANGUAGE plperl;
ERROR:  Useless use of sort in scalar context at line 1.
CONTEXT:  PL/Perl anonymous code block
-- make sure functions marked as VOID without an explicit return work
CREATE OR REPLACE FUNCTION myfuncs() RETURNS void AS $$
   $_SHARED{myquote} = sub {
       my $arg = shift;
       $arg =~ s/(['\\])/\\$1/g;
       return "'$arg'";
   };
$$ LANGUAGE plperl;
SELECT myfuncs();
 myfuncs 
---------
 
(1 row)

-- make sure we can't return an array as a scalar
CREATE OR REPLACE FUNCTION text_arrayref() RETURNS text AS $$
	return ['array'];
$$ LANGUAGE plperl;
SELECT text_arrayref();
ERROR:  cannot convert Perl array to non-array type text
CONTEXT:  PL/Perl function "text_arrayref"
--- make sure we can't return a hash as a scalar
CREATE OR REPLACE FUNCTION text_hashref() RETURNS text AS $$
	return {'hash'=>1};
$$ LANGUAGE plperl;
SELECT text_hashref();
ERROR:  cannot convert Perl hash to non-composite type text
CONTEXT:  PL/Perl function "text_hashref"
---- make sure we can't return a blessed object as a scalar
CREATE OR REPLACE FUNCTION text_obj() RETURNS text AS $$
	return bless({}, 'Fake::Object');
$$ LANGUAGE plperl;
SELECT text_obj();
ERROR:  cannot convert Perl hash to non-composite type text
CONTEXT:  PL/Perl function "text_obj"
----- make sure we can't return a scalar ref
CREATE OR REPLACE FUNCTION text_scalarref() RETURNS text AS $$
	my $str = 'str';
	return \$str;
$$ LANGUAGE plperl;
SELECT text_scalarref();
ERROR:  PL/Perl function must return reference to hash or array
CONTEXT:  PL/Perl function "text_scalarref"
-- check safe behavior when a function body is replaced during execution
CREATE OR REPLACE FUNCTION self_modify(INTEGER) RETURNS INTEGER AS $$
   spi_exec_query('CREATE OR REPLACE FUNCTION self_modify(INTEGER) RETURNS INTEGER AS \'return $_[0] * 3;\' LANGUAGE plperl;');
   spi_exec_query('select self_modify(42) AS a');
   return $_[0] * 2;
$$ LANGUAGE plperl;
SELECT self_modify(42);
 self_modify 
-------------
          84
(1 row)

SELECT self_modify(42);
 self_modify 
-------------
         126
(1 row)