create table table_a(
id varchar(20),
name varchar(20),
*** varchar(20),
age varchar(20),
loaddate varchar(20)
);create table table_b(
id varchar(20),
name varchar(20),
*** varchar(20),
age varchar(20),
loaddate varchar(20)
);truncate table table_a;
truncate table table_b;
insert into "ora_oauth"."test_a" ("id", "name", "***", "student_no", "loaddate", "rowid") values ('1', '小明', '男', '27', '20200520', 'aaacokaaeaaaawjaaa');
insert into "ora_oauth"."test_a" ("id", "name", "***", "student_no", "loaddate", "rowid") values ('2', '小紅', '女', '28', '20200520', 'aaacokaaeaaaawjaab');
insert into "ora_oauth"."test_a" ("id", "name", "***", "student_no", "loaddate", "rowid") values ('4', '王五', '男', '30', '20200520', 'aaacokaaeaaaawjaac');
insert into "ora_oauth"."test_b" ("id", "name", "***", "student_no", "loaddate", "rowid") values ('1', '小明', '男', '27', '20200529', 'aaacolaaeaaaawraaa');
insert into "ora_oauth"."test_b" ("id", "name", "***", "student_no", "loaddate", "rowid") values ('2', '小紅', '女', '29', '20200529', 'aaacolaaeaaaawraab');
insert into "ora_oauth"."test_b" ("id", "name", "***", "student_no", "loaddate", "rowid") values ('3', '小張', '男', '24', '20200529', 'aaacolaaeaaaawraac');
commit;
merge into table_a a1
using (select id,name,***,student_no,loaddate from table_b a
where not exists(select * from table_a b
where a.id = b.id
and a.name = b.name
and a.*** = b.***
and a.age = b.age)) b1
on (a1.id = b1.id)
when matched then
update set a1.name = b1.name,
a1.*** = b1.***,
a1.age = b1.age,
a1.loaddate = b1.loaddate
when not matched then
insert(id,name,***,age,loaddate) values(b1.id,b1.name,b1.***,b1.age,b1.loaddate);
commit;
最後預期結果：新增小張資料與更新小紅年齡與日期
1 小明 男 27 20200520
2 小紅 女 29 20200529
4 王五 男 30 20200520
3 小張 男 24 20200529
--比對test_b多出的資料，與不一樣的資料
(select id,name,***,student_no,loaddate from test_b a
where not exists(select * from test_a b
where a.id = b.id
and a.name = b.name
and a.*** = b.***
and a.student_no = b.student_no));
結果：3 小張 男 24 20200529
2 小紅 女 29 20200529
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