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	plperl's default handling of bool arguments or results is not terribly satisfactory, since Perl doesn't consider the string 'f' to be false. Ideally we'd just fix that, but the backwards-compatibility hazard would be substantial. Instead, build a TRANSFORM module that can be optionally applied to provide saner semantics. Perhaps usefully, this is also about the minimum possible skeletal example of a plperl transform module; so it might be a better starting point for user-written transform modules than hstore_plperl or jsonb_plperl. Ivan Panchenko Discussion: https://postgr.es/m/1583013317.881182688@f390.i.mail.ru
		
			
				
	
	
		
			98 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			98 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| CREATE EXTENSION bool_plperlu CASCADE;
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| NOTICE:  installing required extension "plperlu"
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| --- test transforming from perl
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| CREATE FUNCTION perl2int(int) RETURNS bool
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| LANGUAGE plperlu
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| TRANSFORM FOR TYPE bool
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| AS $$
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| return shift;
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| $$;
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| CREATE FUNCTION perl2text(text) RETURNS bool
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| LANGUAGE plperlu
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| TRANSFORM FOR TYPE bool
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| AS $$
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| return shift;
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| $$;
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| CREATE FUNCTION perl2undef() RETURNS bool
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| LANGUAGE plperlu
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| TRANSFORM FOR TYPE bool
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| AS $$
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| return undef;
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| $$;
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| SELECT perl2int(1);
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|  perl2int 
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| ----------
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|  t
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| (1 row)
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| 
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| SELECT perl2int(0);
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|  perl2int 
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| ----------
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|  f
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| (1 row)
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| 
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| SELECT perl2text('foo');
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|  perl2text 
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| -----------
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|  t
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| (1 row)
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| 
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| SELECT perl2text('');
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|  perl2text 
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| -----------
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|  f
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| (1 row)
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| 
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| SELECT perl2undef() IS NULL AS p;
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|  p 
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| ---
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|  t
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| (1 row)
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| 
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| --- test transforming to perl
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| CREATE FUNCTION bool2perl(bool, bool, bool) RETURNS void
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| LANGUAGE plperlu
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| TRANSFORM FOR TYPE bool
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| AS $$
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| my ($x, $y, $z) = @_;
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| 
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| die("NULL mistransformed") if (defined($z));
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| die("TRUE mistransformed to UNDEF") if (!defined($x));
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| die("FALSE mistransformed to UNDEF") if (!defined($y));
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| die("TRUE mistransformed") if (!$x);
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| die("FALSE mistransformed") if ($y);
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| $$;
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| SELECT bool2perl (true, false, NULL);
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|  bool2perl 
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| -----------
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|  
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| (1 row)
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| 
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| --- test selecting bool through SPI
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| CREATE FUNCTION spi_test()  RETURNS void
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| LANGUAGE plperlu
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| TRANSFORM FOR TYPE bool
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| AS $$
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| my $rv = spi_exec_query('SELECT true t, false f, NULL n')->{rows}->[0];
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| 
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| die("TRUE mistransformed to UNDEF in SPI") if (!defined ($rv->{t}));
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| die("FALSE mistransformed to UNDEF in SPI") if (!defined ($rv->{f}));
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| die("NULL mistransformed in SPI") if (defined ($rv->{n}));
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| die("TRUE mistransformed in SPI") if (!$rv->{t});
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| die("FALSE mistransformed in SPI") if ($rv->{f});
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| $$;
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| SELECT spi_test();
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|  spi_test 
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| ----------
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|  
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| (1 row)
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| 
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| DROP EXTENSION plperlu CASCADE;
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| NOTICE:  drop cascades to 6 other objects
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| DETAIL:  drop cascades to function spi_test()
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| drop cascades to extension bool_plperlu
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| drop cascades to function perl2int(integer)
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| drop cascades to function perl2text(text)
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| drop cascades to function perl2undef()
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| drop cascades to function bool2perl(boolean,boolean,boolean)
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