ORA-38104: ON 子句中引用的列无法更新 c.emp_id

我有两张简单的桌子

CREATE TABLE employee (
  emp_id INT PRIMARY KEY,
  first_name VARCHAR(40),
  last_name VARCHAR(40),
  birth_day DATE,
  sex VARCHAR(1),
  salary INT,
  super_id INT,
  branch_id INT
);

CREATE TABLE biodata (
  emp_id INT PRIMARY KEY,
  first_name VARCHAR(40),
  last_name VARCHAR(40),
  birth_day DATE,
  sex VARCHAR(1)
);

我想合并它

merge into biodata c
using employee e
on (c.emp_id = e.emp_id)
when matched then
  update set
  c.emp_id=e.emp_id,
  c.first_name=e.first_name,
  c.last_name=e.last_name,
  c.birth_day=e.birth_day,
  c.sex=e.sex
when not matched then
  insert VALUES(e.emp_id,e.first_name,e.last_name,e.birth_day,e.sex);

但甲骨文说：

ORA-38104： ON 子句中引用的列无法更新： c.emp_id

只需删除c.emp_id=e.emp_id from UPDATE条款，因为它不相关

(UPDATE将在表的记录上完成biodata对于什么条件c.emp_id = e.emp_id很满意。所以要更新的记录已经有相同的emp_id as e.emp_id).

merge into biodata c
using employee e
on (c.emp_id = e.emp_id)
when matched then
  update set
  --c.emp_id=e.emp_id,
  c.first_name=e.first_name,
  c.last_name=e.last_name,
  c.birth_day=e.birth_day,
  c.sex=e.sex
when not matched then
  insert VALUES(e.emp_id,e.first_name,e.last_name,e.birth_day,e.sex);

Cheers!!