-- create table if not EXISTS atmp(oid int8 PRIMARY key);
-- INSERT into atmp values(1) on conflict(oid) do update set OID = 1;
-- INSERT into atmp values(2) on conflict(oid) do update set OID = 2;
-- INSERT into atmp values(3) on conflict(oid) do update set OID = 3;
-- INSERT into atmp values(1) on conflict(oid) do update set OID = 1;
--
-- create table if not EXISTS atmp2(oid int8 PRIMARY key);
-- INSERT into atmp2 values(1) on conflict(oid) do update set OID = 1;
-- INSERT into atmp2 values(4) on conflict(oid) do update set OID = 4;
-- create table if not EXISTS atmpret(oid int8 PRIMARY key);
--
-- select * from atmp natural join atmp2;
-- select * from atmp as a inner join atmp2 as b on a.oid = b.oid ;
-- select * from atmp as a left join atmp2 as b on a.oid = b.oid ;
-- select * from atmp as a full join atmp2 as b on a.oid = b.oid ;
-- select * from atmp as a right join atmp2 as b on a.oid = b.oid ;
-- select * from atmp as a join atmp2 as b on a.oid = b.oid ;
--求並
DELETE from atmpret;
insert into atmpret ( select * from atmp UNION select * from atmp2) on conflict(OID) do update set OID = (select * from atmp UNION select * from atmp2);
select * from atmpret;
--求交集
DELETE from atmpret;
insert into atmpret (select * from atmp INTERSECT select * from atmp2) on conflict(OID) do update set OID = (select * from atmp INTERSECT select * from atmp2);
select * from atmpret;
--求差 A- B
DELETE from atmpret;
insert into atmpret (select * from atmp EXCEPT select * from atmp2) on conflict(OID) do update set OID = (select * from atmp EXCEPT select * from atmp2);
select * from atmpret;
--求對稱差
DELETE from atmpret;
insert into atmpret (((select * from atmp EXCEPT select * from atmp2)) UNION ((select * from atmp2 EXCEPT select * from atmp))) on conflict(OID) do update set OID = (((select * from atmp EXCEPT select * from atmp2)) UNION ((select * from atmp2 EXCEPT select * from atmp)));
select * from atmpret;
效率如何沒測試過, 有待測試, 但是應該比自己拼接方便快捷