如何复制多行(Oracle)

Question

我正在尝试创建一个将复制表的多行(或只有一行)并为每行插入增加ID的过程.

我的问题是,在我的程序中,我使用游标选择要复制的行,当我选择所有没有WHERE条件的行时,光标一切正常.但是当我设置WHERE条件只选择一行时......没有任何反应

这是我的程序

CREATE OR REPLACE PROCEDURE DuplicateEmployee (p_EmployeeID IN Employee.id%TYPE)
 AS
  p_New_EmployeeID Employee.id%TYPE;
  CURSOR c_DuplicateEmployee IS
    SELECT *
        FROM Employee
        WHERE Employee.id = p_EmployeeID; -- if this line is deleted all content is duplicated
  row_Employee c_DuplicateEmployee%ROWTYPE;
    BEGIN
      FOR myEmployee IN c_DuplicateEmployee LOOP
          p_New_EmployeeID := employee_seq.NEXTVAL;
          INSERT INTO Employee(id, first_name, last_name, start_date, end_date, salary, city, description)
            VALUES(p_New_EmployeeID, myEmployee.first_name, myEmployee.last_name, myEmployee.start_date, myEmployee.end_date, myEmployee.salary, myEmployee.city, myEmployee.description);
      END LOOP;
    COMMIT;
   END DuplicateEmployee;

我知道在这个示例中有一个选择要复制的主键的过程是没有意义的,但在我的生产基础中,它将用于选择外键.

Bellow是创建测试表所需的代码,以及我用于此过程的SEQUENCE

CREATE TABLE Employee
  (
    ID         VARCHAR2(4 BYTE) NOT NULL,
    First_Name VARCHAR2(10 BYTE),
    Last_Name  VARCHAR2(10 BYTE),
    Start_Date DATE,
    End_Date DATE,
    Salary      NUMBER(8,2),
    City        VARCHAR2(10 BYTE),
    Description VARCHAR2(15 BYTE)
  );
INSERT
INTO Employee
    (ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
  VALUES
    ('01', 'Jason', 'Martin', to_date('19960725','YYYYMMDD'), to_date('20060725','YYYYMMDD'), 1234.56, 'Toronto', 'Programmer');
INSERT
INTO Employee
    (ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
  VALUES
    ('02', 'Alison', 'Mathews', to_date('19760321','YYYYMMDD'), to_date('19860221','YYYYMMDD'), 6661.78, 'Vancouver', 'Tester');
INSERT
INTO Employee
    (ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
  VALUES
    ('03', 'James', 'Smith', to_date('19781212','YYYYMMDD'), to_date('19900315','YYYYMMDD'), 6544.78, 'Vancouver', 'Tester');
INSERT
INTO Employee
    (ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
  VALUES
    ('04', 'Celia', 'Rice', to_date('19821024','YYYYMMDD'), to_date('19990421','YYYYMMDD'), 2344.78, 'Vancouver', 'Manager');
INSERT
INTO Employee
    (ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
  VALUES
    ('05', 'Robert', 'Black', to_date('19840115','YYYYMMDD'), to_date('19980808','YYYYMMDD'), 2334.78, 'Vancouver', 'Tester');
 INSERT
INTO Employee
    (ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
  VALUES
    ('06', 'Linda', 'Green', to_date('19870730','YYYYMMDD'), to_date('19960104','YYYYMMDD'), 4322.78, 'New York', 'Tester');
INSERT
INTO Employee
    (ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
VALUES
    ('07', 'David', 'Larry', to_date('19901231','YYYYMMDD'), to_date('19980212','YYYYMMDD'), 7897.78, 'New York', 'Manager');
INSERT
INTO Employee
    (ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
VALUES
    ('08', 'James', 'Cat', to_date('19960917','YYYYMMDD'), to_date('20020415','YYYYMMDD'), 1232.78, 'Vancouver', 'Tester');

这里是将管理主键(ID)的序列

CREATE SEQUENCE "TEST"."EMPLOYEE_SEQ" MINVALUE 1 MAXVALUE 999999999999999999999999999 INCREMENT BY 1 START WITH 1 NOCACHE ORDER NOCYCLE ;

这里是执行程序的代码

BEGIN
  employeepackage.duplicateemployee(5);
END;

我真的不明白为什么当它正在努力复制所有行时它不能正常工作？对于少于2行的游标有限制吗？

任何帮助将非常感激 ;)

Answer 1

你为什么需要一个游标？您可以直接使用SQL执行此操作:

INSERT INTO Employee(id, first_name, last_name, 
                     start_date, end_date, 
                     salary, city, description)
SELECT employee_seq.NEXTVAL, e.first_name, e.last_name,
       e.start_date, e.end_date, 
       e.salary, e.city, e.description
FROM Employee e
WHERE e.id = p_EmployeeID;

无论如何,实际的问题是你ID是一个VARCHAR2(4),而你认为​​它是一个NUMBER.你实际上没有雇员ID = 5,但你确实有一个雇员ID = '05'.所以没有改变任何东西,你的程序已经有效:

BEGIN
  employeepackage.duplicateemployee('05');
END;

当然,更改数据类型是有意义的ID.