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=5 db2 => alter table test alter pay set not null DB20000I SQL 命令成功完成。 db2 => alter table pay add foreign key (depid) references department (depid) db2 => reorg table pay db2 => alter table pay alter pay drop not null db2 => insert into pay (name,depid) select name,depid from phone