db2 => create table test (name char(8) not null primary key,depid smallint,pay bigint)DB20000I SQL 命令成功完成。db2 => create table test1 (name char(8) not null primary key,depid smallint references department (depid),pay bigint)DB20000I SQL 命令成功完成。db2 => update department set depmanager=‘abc‘ where depid=5db2 => alter table test alter pay set not nullDB20000I SQL 命令成功完成。db2 => alter table pay add foreign key (depid) references department (depid)db2 => reorg table paydb2 => alter table pay alter pay drop not nulldb2 => insert into pay (name,depid) select name,depid from phone