Triggers should return TRIGGER not OPAQUE. Looks like this script got

tglsfdc · tglsfdc · commit 1ade4b33f635 · 2004-12-30T00:30:40.000Z
overlooked in 7.3 updates.  Not a critical fix but avoids a notice when
the resulting SQL script is executed.
diff --git a/contrib/oracle/Ora2Pg.pm b/contrib/oracle/Ora2Pg.pm
@@ -881,7 +881,7 @@ print STDERR "Add triggers definition...\n" if ($self->{debug});
 				if ($self->{export_schema}) {
 					$sql_output .= "SET search_path = $self->{schema}, pg_catalog;\n\n";
 				}
-				$sql_output .= "CREATE FUNCTION pg_fct_\L$trig->[0]\E () RETURNS OPAQUE AS '\n$trig->[4]\n' LANGUAGE 'plpgsql'\n\n";
+				$sql_output .= "CREATE FUNCTION pg_fct_\L$trig->[0]\E () RETURNS TRIGGER AS '\n$trig->[4]\n' LANGUAGE 'plpgsql'\n\n";
 				$sql_output .= "CREATE TRIGGER \L$trig->[0]\E\n\t$trig->[1] $trig->[2] ON \"\L$trig->[3]\E\" FOR EACH ROW\n\tEXECUTE PROCEDURE pg_fct_\L$trig->[0]\E();\n\n";
 			}
 		}

Original file line number	Diff line number	Diff line change
`@@ -881,7 +881,7 @@ print STDERR "Add triggers definition...\n" if ($self->{debug});`
`881`	`881`	`if ($self->{export_schema}) {`
`882`	`882`	`$sql_output .= "SET search_path = $self->{schema}, pg_catalog;\n\n";`
`883`	`883`	`}`
`884`		`- $sql_output .= "CREATE FUNCTION pg_fct_\L$trig->[0]\E () RETURNS OPAQUE AS '\n$trig->[4]\n' LANGUAGE 'plpgsql'\n\n";`
	`884`	`+ $sql_output .= "CREATE FUNCTION pg_fct_\L$trig->[0]\E () RETURNS TRIGGER AS '\n$trig->[4]\n' LANGUAGE 'plpgsql'\n\n";`
`885`	`885`	`$sql_output .= "CREATE TRIGGER \L$trig->[0]\E\n\t$trig->[1] $trig->[2] ON \"\L$trig->[3]\E\" FOR EACH ROW\n\tEXECUTE PROCEDURE pg_fct_\L$trig->[0]\E();\n\n";`
`886`	`886`	`}`
`887`	`887`	`}`