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|
-- test plperl triggers
CREATE TABLE trigger_test (
i int,
v varchar
);
CREATE OR REPLACE FUNCTION trigger_data() RETURNS trigger LANGUAGE plperl AS $$
# make sure keys are sorted for consistent results - perl no longer
# hashes in repeatable fashion across runs
foreach my $key (sort keys %$_TD)
{
my $val = $_TD->{$key};
# relid is variable, so we can not use it repeatably
$val = "bogus:12345" if $key eq 'relid';
if (! defined $val)
{
elog(NOTICE, "\$_TD->\{$key\} = NULL");
}
elsif (not ref $val)
{
elog(NOTICE, "\$_TD->\{$key\} = '$val'");
}
elsif (ref $val eq 'HASH')
{
my $str = "";
foreach my $rowkey (sort keys %$val)
{
$str .= ", " if $str;
my $rowval = $val->{$rowkey};
$str .= "'$rowkey' => '$rowval'";
}
elog(NOTICE, "\$_TD->\{$key\} = \{$str\}");
}
elsif (ref $val eq 'ARRAY')
{
my $str = "";
foreach my $argval (@$val)
{
$str .= ", " if $str;
$str .= "'$argval'";
}
elog(NOTICE, "\$_TD->\{$key\} = \[$str\]");
}
}
return undef; # allow statement to proceed;
$$;
CREATE TRIGGER show_trigger_data_trig
BEFORE INSERT OR UPDATE OR DELETE ON trigger_test
FOR EACH ROW EXECUTE PROCEDURE trigger_data(23,'skidoo');
insert into trigger_test values(1,'insert');
update trigger_test set v = 'update' where i = 1;
delete from trigger_test;
DROP TRIGGER show_trigger_data_trig on trigger_test;
DROP FUNCTION trigger_data();
CREATE OR REPLACE FUNCTION valid_id() RETURNS trigger AS $$
if (($_TD->{new}{i}>=100) || ($_TD->{new}{i}<=0))
{
return "SKIP"; # Skip INSERT/UPDATE command
}
elsif ($_TD->{new}{v} ne "immortal")
{
$_TD->{new}{v} .= "(modified by trigger)";
return "MODIFY"; # Modify tuple and proceed INSERT/UPDATE command
}
else
{
return; # Proceed INSERT/UPDATE command
}
$$ LANGUAGE plperl;
CREATE TRIGGER "test_valid_id_trig" BEFORE INSERT OR UPDATE ON trigger_test
FOR EACH ROW EXECUTE PROCEDURE "valid_id"();
INSERT INTO trigger_test (i, v) VALUES (1,'first line');
INSERT INTO trigger_test (i, v) VALUES (2,'second line');
INSERT INTO trigger_test (i, v) VALUES (3,'third line');
INSERT INTO trigger_test (i, v) VALUES (4,'immortal');
INSERT INTO trigger_test (i, v) VALUES (101,'bad id');
SELECT * FROM trigger_test;
UPDATE trigger_test SET i = 5 where i=3;
UPDATE trigger_test SET i = 100 where i=1;
SELECT * FROM trigger_test;
CREATE OR REPLACE FUNCTION immortal() RETURNS trigger AS $$
if ($_TD->{old}{v} eq $_TD->{args}[0])
{
return "SKIP"; # Skip DELETE command
}
else
{
return; # Proceed DELETE command
};
$$ LANGUAGE plperl;
CREATE TRIGGER "immortal_trig" BEFORE DELETE ON trigger_test
FOR EACH ROW EXECUTE PROCEDURE immortal('immortal');
DELETE FROM trigger_test;
SELECT * FROM trigger_test;
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