获取一个表中的数据插入到另一个表
insert into studentsNew(id,name,sex,age) select id,name,sex,age from students where id between 30000 and 100000;
设置某列的默认值
alter table studentsNew alter column begindate set default 20171222;
alter table studentsNew alter column enddate set default 99991231;
更新原表关联数据，插入新增数据（新表中少两列字段）
UPDATE students tt set enddate=20171223 where exists(select * from stu ss where tt.id=ss.id);
alter table students alter column begindate set default 20171223;
alter table students alter column enddate set default 99991231;
insert into students(id,name,sex,age) select id,name,sex,age from stu;
select * from students st, stu ss
where st.id=ss.id
删除表1中两个表相同数据，再把表2数据全部插入到表1
DELETE from students tt WHERE exists(select * from stu ss where tt.id=ss.id);
insert into students(id,name,sex,age) select id,name,sex,age from stu;
查询30000-100000中间数据
select * from students where id>30000 and id<100000
select * from students where id between 30000 and 100000
获取一个表中的数据插入到另一个表
insert into studentsNew(id,name,sex,age) select id,name,sex,age from students where id between 30000 and 100000;
设置某列的默认值
alter table studentsNew alter column begindate set default 20171222;
alter table studentsNew alter column enddate set default 99991231;
查询两表的关联数据
select * from studentsNew ss,stu_test tt where ss.id=tt.id
更新表一列的数据
update stu_test set begindate=20171223
