postgresql - update increment of serial field from several records in postgres -

i want change increment value of columns use sequencial ids. how can it?

i tried following 2 approaches, both failed:

update information_schema.sequences set increment=1; 

this doesn't work because information_schema.sequences it's view.

i tried use alter sequence, adding @ end, like:

alter sequence a.sequence_name increment 2 (select * information_schema.sequences) 

but syntax error.

how can this?

try using setval docs

or

alter sequence... restart with... described here

edited twice

sample how change sequences in owned schema:

do $$ declare record; begin in (select * information_schema.sequences) loop execute $e$alter sequence $e$||i.sequence_name||$e$ increment 2$e$; end loop; end; $$ ;