Обсуждение: loops

On Tue, Jun 02, 2009 at 11:32:03AM -0400, Esneiker wrote:
> Hello, can anybody tell me how to do loops in postgres?

As usually, the fine manual:

http://www.postgresql.org/docs/current/interactive/plpgsql-control-structures.html

Best regards,

depesz

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Esneiker wrote:
>
> Hello, can anybody tell me how to do loops in postgres?
>

SQL, the query language, has no such control structures.  SQL is a
'declarative' language rather than a procedural one.

pl/pgsql stored procedures do, however, as they embed SQL in a
procedural context.
depesz posted the link to the appropriate docs.

On Tue, Jun 2, 2009 at 12:24 PM, John R Pierce <pierce@hogranch.com> wrote:
> Esneiker wrote:
>>
>> Hello, can anybody tell me how to do loops in postgres?
>>
>
> SQL, the query language, has no such control structures.  SQL is a
> 'declarative' language rather than a procedural one.
>
> pl/pgsql stored procedures do, however, as they embed SQL in a procedural
> context. depesz posted the link to the appropriate docs.

you can simulate simple loops with 'generate_series' and other set
returning functions like unnest or equivalent:

insert into foo(foo_id) select generate_series(1,10) v;
insert  into foo(val) select unnest(current_schemas(true));