全是数据库的操作，全是SQL语句，有的对，有的不对，练手用的
create table MMCR006(ID varchar(5), NAME varchar(30));
select * from mmcr006
alter table mmcr006 add STUDENT varchar(15)
alter table mmcr006 add GRADE varchar(111)
alter table mmcr006 drop COLUMN grade
insert into mmcr006 values('b','c','d','null')
reorg table BM2MES.MMCR006
alter table mmcr006 add constraint PRIMARY KEY(ID)
update mmcr006 set ID = 'q' where name = '1'
select *(delete from mmcr006 where id = 'a')
create table MMCR007(MAT_NO varchar(5), ORDER_NO varchar(30));
select * from mmcr007
alter table mmcr007 add IPAGEINDEX varchar(50)
insert into mmcr007 values('b','c','d')
select * from mmcr006 inner join mmcr007 on MMCR006.ID = mmcr007.MAT_NO
