intersect 相交，except 相减，union 合并 ，union all 合并全部区别

select * from PV_ENCOUNTER where CODE_PV like '200630001%'
intersect --相交的
select * from PV_ENCOUNTER where CODE_PV like '2006300011'

select * from PV_ENCOUNTER where CODE_PV like '200630001%'
except--不相交的
select * from PV_ENCOUNTER where CODE_PV like '2006300011'

select * from PV_ENCOUNTER where CODE_PV like '200630001%'
union--相同的会去重
select * from PV_ENCOUNTER where CODE_PV like '2006300011'

select * from PV_ENCOUNTER where CODE_PV like '200630001%'
union all--相同的不会去重
select * from PV_ENCOUNTER where CODE_PV like '2006300011'