Example
drop table table01;
drop table table02;
create table table01 (
code int,
name varchar(50),
old int
);
create table table02 (
code int,
name varchar(50),
old int
);
truncate table table01;
insert into table01 values (1, 'A', 10);
insert into table01 values (9, 'B', 12);
insert into table01 values (3, 'C', 14);
insert into table01 values (4, 'D', 16);
insert into table01 values (5, 'E', 18);
truncate table table02;
insert into table02 values (1, 'AA', null);
insert into table02 values (2, 'BB', 123);
insert into table02 values (3, 'CC', null);
insert into table02 values (4, 'DD', null);
insert into table02 values (5, 'EE', null);
select * from table01 a order by 2;
select * from table02 a order by 2;
--
merge into table02 a using (
select b.code, b.old from table01 b
) c on (
a.code = c.code
)
when matched then update set a.old = c.old
;
--
select a.*, b.* from table01 a
inner join table02 b on a.code = b.codetable01;
select * from table01 a
where
exists
(
select 'x' from table02 b where a.code = b.codetable01
);
select * from table01 a where a.code in (select b.codetable01 from table02 b);
--
select * from table01 a
where
not exists
(
select 'x' from table02 b where a.code = b.codetable01
);
select * from table01 a where a.code not in (select b.codetable01 from table02 b);
