SP2-0552：未声明绑定变量“NEW”

Question

我正在尝试学习 pl/sql 触发器。我正在尝试通过跟踪教程http://www.tutorialspoint.com/plsql/plsql_triggers.htm 创建一个简单的触发器，但出现以下错误。我在互联网上搜索但找不到解决方案。你能帮我解决这个问题吗？

CREATE OR replace TRIGGER display_salary_changes 
  BEFORE DELETE OR INSERT OR UPDATE ON ok.customers 
  FOR EACH ROW 
DECLARE 
    sal_diff NUMBER; 
BEGIN 
    sal_diff := :NEW.salary - :OLD.salary; 
END; 
/ 


Trıgger DISPLAY_SALARY_CHANGES created.

SP2-0552: Bind Variable "NEW" is not declared.

PL/SQL procedure successfully completed.

编辑：我使用的是 Sql Developer 版本 4.1.1

Answer 1

对我有用（来自您的链接的示例，但它与您的帖子基本相同）：

SQL> create table demo (id integer, salary number);

Table created.

SQL> create or replace trigger display_salary_changes
  2  before delete or insert or update on demo
  3  for each row
  4  when (new.id > 0)
  5  declare
  6     sal_diff number;
  7  begin
  8     sal_diff := :new.salary  - :old.salary;
  9     dbms_output.put_line('Old salary: ' || :old.salary);
 10     dbms_output.put_line('New salary: ' || :new.salary);
 11     dbms_output.put_line('Salary difference: ' || sal_diff);
 12  end;
 13  /

Trigger created.

SQL> show errors
No errors.
SQL> insert into demo (id, salary) values (1, 100);
Old salary:
New salary: 100
Salary difference:

1 row created.

SQL> update demo set salary = salary * 1.1 where id = 1;
Old salary: 100
New salary: 110
Salary difference: 10

1 row updated.

在您的示例中显示

Trıgger DISPLAY_SALARY_CHANGES created.

这看起来不像 SQL*Plus 输出。你用的是什么工具？

之后它给出一个关于未定义绑定变量的 SQL*Plus SP2-0552 错误，然后是

PL/SQL procedure successfully completed.

那是什么程序？我怀疑这是脚本的输出，在创建触发器后其他步骤失败。

触发器有效吗？您通常可以在桌面工具中右键单击并检查属性，或在 SQL*Plus 提示符处输入

show errors trigger display_salary_changes

Answer 2

试试这个：

CREATE OR replace TRIGGER test_trg 
  BEFORE DELETE OR INSERT OR UPDATE ON test 
  FOR EACH ROW 
DECLARE 
    sal_diff NUMBER; 
BEGIN 
    sal_diff := :new.d - :old.d; 
END; 
/ 

Answer 3

请您检查一下您的列名。我在下面尝试了你的代码，我得到了输出。

create table test
(
no number(10),
sal number(10)
);

CREATE OR replace TRIGGER test_tr 
  BEFORE DELETE OR INSERT OR UPDATE ON test 
  FOR EACH ROW 
DECLARE 
    sal_diff NUMBER; 
BEGIN 
    sal_diff := :NEW.sal - :OLD.sal; 
    dbms_output.put_line(sal_diff);
END; 
/ 



insert into test values(1,100);

update test set sal=200 where no=1;

输出：

1 rows inserted.


4 rows updated.
100
100
100
100

1 rows inserted.

Answer 4

我认为它缺少“REFERENCING NEW AS NEW OLD AS OLD”这句话：

  CREATE TRIGGER [trigger_name]
  BEFORE INSERT OR UPDATE ON [table_name]
  REFERENCING NEW AS NEW OLD AS OLD
  FOR EACH ROW