mit ir? valoszinuleg csak a group oszlop nevet kell idezojelbe rakni.
a postgres-ben gond nelkul lefut:
```
CREATE TABLE hup AS
select "group", "prefix","value" from (values
('group1', 'a123', '1.2'), ('group1', 'a1234', '1.2'), ('group1', 'a1235', '1.4'),('group2', 'a1234', '1.6'),('group2', 'a12345', '1.6')) as mytable("group", "prefix","value" );
DELETE FROM hup t1
WHERE EXISTS (SELECT 1 FROM hup t2 WHERE t1."group" = t2."group" and t1.value = t2.value and LEFT(t1.prefix, LENGTH(t2.prefix)) = t2.prefix and LENGTH(t2.prefix) < LENGTH(t1.prefix));
```