Re: Get block of N numbers from sequence

Thomas Guettler írta:
> Hi,
>
> how can you get N numbers (without holes) from a sequence?
>
>  Thomas
>
>

# create sequence tmp_seq cache 1000;
CREATE SEQUENCE

From the same client:
# select nextval('tmp_seq');
 nextval
---------
       1
(1 sor)

# select nextval('tmp_seq');
 nextval
---------
       2
(1 sor)

# select nextval('tmp_seq');
 nextval
---------
       3
(1 sor)

# select nextval('tmp_seq');
 nextval
---------
       4
(1 sor)

... (ad nauseum)


From another psql client:

# select nextval('tmp_seq');
 nextval
---------
    1001
(1 sor)

# select nextval('tmp_seq');
 nextval
---------
    1002
(1 sor)

# select nextval('tmp_seq');
 nextval
---------
    1003
(1 sor)

# select nextval('tmp_seq');
 nextval
---------
    1004
(1 sor)

# select nextval('tmp_seq');
 nextval
---------
    1005
(1 sor)

...


You can get up to 1000 (or the number specified as CACHE N)
numbers in a series (without holes) in he same client at once,
you don't even need to be in the same transaction.

Best regards,
Zoltán Böszörményi

--
Bible has answers for everything. Proof:
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----------------------------------
Zoltán Böszörményi
Cybertec Schönig & Schönig GmbH
http://www.postgresql.at/