PL/SQL 中的 If-Else

Question

我想编写一个程序来执行仅允许提款的提款操作，如果帐户中有足够的资金，则更新帐户表并打印消息“交易成功”。否则打印，“数量不足”。 .该过程应以 Account_id 和提款金额为输入。

Account:
ACCNO   NUMBER  PK
CUSTOMER_NAME   VARCHAR2(30)     
BALANCE NUMBER(15,2)     

12345   Williams    23455.6
23456   Robert  43221
34521   John    23449

功能要求：

procedure withdraw(ano number , amt number)

示例输入：

withdraw(12345, 2000);

样本输出：

Transaction successful.

我尝试编写如下代码-

set serveroutput on;
create or replace procedure withdraw(ano number, amt number) is withdraw_operation account%rowtype;
begin
select * into withdraw_operation from account 
if (amt > balance)
then dbms_output.put_line('Transaction successful');
else dbms_output.put_line('Insufficient Amount');
end if;
end; 

但这没有显示任何输出或错误，请帮助。提前致谢！

Answer 1

这没有显示任何输出也没有错误

这很难相信，因为您发布的内容不正确。

---

无论如何：从您发布的内容来看，应该是这样的：

样本数据：

SQL> SET SERVEROUTPUT ON;
SQL>
SQL> SELECT * FROM account;

     ACCNO CUSTOMER    BALANCE
---------- -------- ----------
     12345 Williams    23455,6
     23456 Robert        43221
     34521 John          23449

程序：

SQL> CREATE OR REPLACE PROCEDURE withdraw (ano NUMBER, amt NUMBER)
  2  IS
  3     withdraw_operation  account%ROWTYPE;
  4  BEGIN
  5     SELECT *
  6       INTO withdraw_operation
  7       FROM account
  8      WHERE accno = ano;
  9
 10     IF amt > withdraw_operation.balance
 11     THEN
 12        DBMS_OUTPUT.put_line ('Transaction successful');
 13     ELSE
 14        DBMS_OUTPUT.put_line ('Insufficient Amount');
 15     END IF;
 16  END;
 17  /

Procedure created.

测试：

SQL> EXEC withdraw(12345, 2000);
Insufficient Amount

PL/SQL procedure successfully completed.

SQL>