PL/SQL SELECT INTO 的 ORA-01422 错误，Oracle 匿名块（NOVA 环境）

Question

出现以下错误：ORA-01422：精确提取 returns 多于请求的行数 ORA-6512

PL/SQL 的新手，虽然我知道这个查询应该通过标准 SQL 进行，但我正在尝试弄清楚如何使用 PL/SQL.[=15= 来完成这个查询]

我需要查询 return 邮政编码为“20636”的客户的销售总数

这里是 tables/input:

CREATE TABLE CUSTOMERS
(customerID     INT     PRIMARY KEY,
customerZip     VARCHAR(15) NOT NULL); 

CREATE TABLE SALES
(saleID         INT     PRIMARY KEY,
customerID      INT,
CONSTRAINT SALES_FK1 FOREIGN KEY (customerID) REFERENCES CUSTOMERS(customerID));

INSERT INTO CUSTOMERS (customerID, customerZIP) VALUES (1, '20636');
INSERT INTO CUSTOMERS (customerID, customerZIP) VALUES (2, '20619');
INSERT INTO CUSTOMERS (customerID, customerZIP) VALUES (3, '20650');
INSERT INTO CUSTOMERS (customerID, customerZIP) VALUES (4, '20670');
INSERT INTO CUSTOMERS (customerID, customerZIP) VALUES (5, '20636');

INSERT INTO SALES (saleID, customerID) VALUES (1, 1);
INSERT INTO SALES (saleID, customerID) VALUES (2, 2);
INSERT INTO SALES (saleID, customerID) VALUES (3, 3);
INSERT INTO SALES (saleID, customerID) VALUES (4, 4);
INSERT INTO SALES (saleID, customerID) VALUES (5, 5);

这是我为 PL/SQL 匿名块编写的代码：

DECLARE
customerZip INTEGER;
totalSales INTEGER;
BEGIN
SELECT customerID INTO customerZip from CUSTOMERS where customerZip = '20636';
SELECT COUNT(*) INTO totalSales from SALES where customerID = customerZip;
DBMS_OUTPUT.put_line('We sold ' || totalSales || ' Cars to customers in Zip Code ' || customerZip ||'.');
END;
/

如果我运行这没有在 '20636' 设置两个 customerZIP 属性，它工作正常。一旦我输入多个邮政编码为“20636”的客户记录，我就会收到错误消息。

你能解释一下我在这里做错了什么以及我该如何解决吗？谢谢！

SQL Fiddle link 如果有帮助：http://sqlfiddle.com/#!4/10fc1

Answer 1

你可以使用这样的语句：

SQL> set serveroutput on;
SQL> DECLARE
  v_customerZip CUSTOMERS.customerZip%type:='20636';
  v_customerID  CUSTOMERS.customerID%type;
  totalSales    INTEGER:=0;
  Sales         INTEGER;
BEGIN
 for c in ( SELECT customerID from CUSTOMERS where customerZip = v_customerZip )
 loop
  v_customerID := c.customerID;
  SELECT COUNT(1) INTO Sales from SALES where customerID = v_customerID;
  totalSales := totalSales + Sales;
 end loop; 
  dbms_output.put_line('We sold ' || totalSales || ' Cars to customers in Zip Code ' || v_customerZip ||'.');
END;
/
We sold 2 Cars to customers in Zip Code 20636.

并根据声明部分的需要更改变量 v_customerZip 的值。

或者您可以创建一个过程来完成此任务：

SQL> CREATE OR REPLACE PROCEDURE GET_SALES( v_customerZip CUSTOMERS.customerZip%type ) IS
  v_customerID  CUSTOMERS.customerID%type;
  totalSales    INTEGER:=0;
  Sales         INTEGER;
BEGIN
 for c in ( SELECT customerID from CUSTOMERS where customerZip = v_customerZip )
 loop
  v_customerID := c.customerID;
  SELECT COUNT(1) INTO Sales from SALES where customerID = v_customerID;
  totalSales := totalSales + Sales;
 end loop; 
  dbms_output.put_line('We sold ' || totalSales || ' Cars to customers in Zip Code ' || v_customerZip ||'.');
END;
/
SQL> exec get_sales('&cZ');
Enter value for cz: 20636
We sold 2 Cars to customers in Zip Code 20636.

PL/SQL SELECT INTO 的 ORA-01422 错误，Oracle 匿名块（NOVA 环境）

PL/SQL ORA-01422 Error for SELECT INTO, Oracle Anonymous Block (NOVA Environment)

sql

oracle

plsql

oracle11g

ora-01422