Date: Sat, 11 Jun 2011 17:23:40 +0200
From: Andreas Kretschmer <akretschmer@spamfence.net>
To: pgsql-sql@postgresql.org
Subject: Re: Subselects not allowed?
Message-ID: <20110611152340.GA9062@tux>
References: <201106111701.54145.leif@solumslekt.org>
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Leif Biberg Kristensen <leif@solumslekt.org> wrote:

> Can anybody tell me why this doesn't work?
> 
> pgslekt=> CREATE SEQUENCE sources_source_id_seq START WITH (SELECT 
> MAX(source_id) FROM sources);
> ERROR:  syntax error at or near "("
> LINE 1: CREATE SEQUENCE sources_source_id_seq START WITH (SELECT MAX...
>                                                          ^
> pgslekt=> 
> 
> regards, Leif

You can't do that, but you can do this:

test=# select * from foo;
 i
----
 98
 99
(2 rows)

Time: 0,146 ms
test=*# \ds seq_foo;
No matching relations found.
test=*# do $$ declare m int; begin select into m max(i) from foo; execute 'create sequence seq_foo start with ' || m; end; $$;
DO
Time: 1,115 ms
test=*# \ds seq_foo;
            List of relations
 Schema |  Name   |   Type   |   Owner
--------+---------+----------+------------
 public | seq_foo | sequence | kretschmer
(1 row)

test=*# select * from seq_foo;
 sequence_name | last_value | start_value | increment_by |      max_value      | min_value | cache_value | log_cnt | is_cycled | is_called
---------------+------------+-------------+--------------+---------------------+-----------+-------------+---------+-----------+-----------
 seq_foo       |         99 |          99 |            1 | 9223372036854775807 |         1 |           1 |       1 | f         | f
(1 row)


I'm using 9.1Beta, but it works since 9.0, see:
http://www.depesz.com/index.php/2009/11/01/waiting-for-8-5-do/#more-1535


Andreas
-- 
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