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create table Bookmarks (Id varchar(10), BookmarkNumber int);
insert into Bookmarks values ('dd', 1);
insert into Bookmarks values ('aa', 2);
insert into Bookmarks values ('dd', 3);
insert into Bookmarks values ('tt', 5);
insert into Bookmarks values ('ff', 27);
insert into Bookmarks values ('uu', 28);
6 rows affected
insert into Bookmarks (Id, BookmarkNumber)
select 'xx', value
from (
select min(value) as value
from generate_series(1, 99)
left join Bookmarks on BookmarkNumber = value
where BookmarkNumber is null
) x
1 rows affected
select * from Bookmarks order by 2;
| Id | BookmarkNumber |
|---|---|
| dd | 1 |
| aa | 2 |
| dd | 3 |
| xx | 4 |
| tt | 5 |
| ff | 27 |
| uu | 28 |