oracle - 带光标的 pl/sql 更新过程卡住

Question

我编写了一个程序，它使用游标来更新这些表中的某些行-这是程序：

DECLARE
   -- Local variables here
   CURSOR s
   IS
      (SELECT UNIQUE *
         FROM Sellers
        WHERE ID_Seller NOT IN (SELECT ID_Seller
                                  FROM Sellers NATURAL JOIN Sales));

   s_rec   Sellers%ROWTYPE;
BEGIN
   -- Test statements here
   OPEN s;

   LOOP
      FETCH s INTO s_rec;

      EXIT WHEN s%NOTFOUND;
      DBMS_OUTPUT.put_line (s_rec.ID_Seller);
      DBMS_OUTPUT.put_line (s_rec.Salary);
      updateSalary (s_rec.ID_Seller, s_rec.Salary - 50);
   END LOOP;

   CLOSE s;
END;

这是程序 updateSalary：

CREATE OR REPLACE PROCEDURE updateSalary (ID_S        IN VARCHAR2,
                                          newSalary   IN FLOAT)
IS
BEGIN
   UPDATE Sellers s
      SET s.salary = newSalary
    WHERE s.ID_Seller = ID_S;
END updateSalary;

运行程序时，它卡在更新命令上。程序有什么问题？

Answer 1

You need to add **FOR UPDATE** IN CURSOR TO UPDATE THE TABLE

Answer 2

为了更新游标内的表，您需要以“FOR UPDATE”模式打开游标，添加到您的查询“FOR UPDATE”：

(SELECT UNIQUE *
     FROM Sellers
    WHERE ID_Seller NOT IN (SELECT ID_Seller
                              FROM Sellers NATURAL JOIN Sales) FOR UPDATE);