Re: Subselects not allowed?

Guillaume Lelarge <guillaume(at)lelarge(dot)info> writes:
> On Sat, 2011-06-11 at 17:01 +0200, Leif Biberg Kristensen 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 "("

> Because it's not supported. The START clause expects a value, not a
> subquery.

More generally, there are no "utility" statements in PG that accept
non-constant expressions in their parameters. (A utility statement is
anything other than SELECT, INSERT, UPDATE, DELETE.)

There's been occasional speculation about changing that, but it would
take a significant amount of work I think.

regards, tom lane