Hi, all:
PostgreSQL version : 10.3. I use "nextval" in the sql , but I think the result is not right, maybe it is a bug.
The test case as bellow:
create sequence seq1;
select nextval('seq1');
create table tx1(id1 int, id2 int);
insert into tx1 select generate_series(1,100), random()*102;
explain verbose select * from tx1 where id2 = nextval('seq1');;
select * from tx1 where id2 = nextval('seq1');
postgres=# explain verbose select * from tx1 where id2 = nextval('seq1');;
QUERY PLAN
------------------------------------------------------------
Seq Scan on public.tx1 (cost=0.00..43.90 rows=11 width=8)
Output: id1, id2
Filter: (tx1.id2 = nextval('seq1'::regclass))
(3 rows)
postgres=# select * from tx1 where id2 = nextval('seq1'); -- here, may be the result is not right
id1 | id2
-----+-----
56 | 57
(1 row)
:: I think "nextval('seq1')" equal 2, so " select * from tx1 where id2 = nextval('seq1')" equals " select * from tx1 where id2 = 2", is it ?
Thanks,
Wanglin
