Alter table in stored procedure

Hi, I have table with serial column: create table kard_ser (kard_ser serial not null ); I would like to change starting serial number after some time and this should be done by all users (public), so I decide to use stored procedure which will receive starting serial number: create dba procedure pom_test(ser_num int) alter table kard_ser modify kard_ser serial (ser_num) not null; end procedure; When I try to execute procedure I get syntax error on alter table statement. I don't know SPL very well, please help.