PL/SQL 错误 - 精确提取返回的行数超过了请求的行数答案

【问题标题】：PL/SQL Error - exact fetch returns more than requested number of rowsPL/SQL 错误 - 精确提取返回的行数超过了请求的行数
【发布时间】：2018-01-15 10:29:52
【问题描述】：

我目前正在尝试编写一个 PL/SQL 脚本，该脚本将从我的 saleinv 表中收集与用户输入的序列号匹配的信息。目前，我的代码正在返回错误错误消息是 ORA-01422：精确提取返回的行数超过了请求的行数。如果有人可以向我解释如何解决该问题，将不胜感激。我的代码如下。

    ACCEPT p_saleinv PROMPT 'Enter sales invoice number: '
    VARIABLE g_output VARCHAR2(4000)

    DECLARE

 v_ABC NUMBER(4);
 v_DEF EXCEPTION;
 v_freightcost car.freightcost%TYPE;
 v_totalcost car.totalcost%TYPE;

CURSOR saleinvoicelist IS
SELECT *
FROM saleinv
WHERE saleinv = '&p_saleinv';

BEGIN

SELECT COUNT(*)
INTO v_ABC  
FROM saleinv
WHERE saleinv = '&p_saleinv';

SELECT freightcost,totalcost
INTO  v_freightcost,v_totalcost
FROM car c, saleinv si
WHERE  c.serial = si.serial
AND   c.cname  = si.cname;


IF v_ABC = '0' THEN

  RAISE v_DEF;

ELSE 

   FOR v_saleinv IN saleinvoicelist LOOP
      :g_output := :g_output||TRIM(v_saleinv.saleinv)||' ';
      :g_output := :g_output||TRIM(v_saleinv.cname)||' ';
      :g_output := :g_output||TRIM(v_saleinv.saledate)||' ';
      :g_output := :g_output||TRIM(v_saleinv.serial)||' ';
      :g_output := :g_output||TO_CHAR(v_freightcost,'122345.69')||CHR(10);
      :g_output := :g_output||TO_CHAR(v_saleinv.tax,'12345.99')||' ';
      :g_output := :g_output||TO_CHAR(v_saleinv.licfee,'123.76')||' ';
      :g_output := :g_output||TO_CHAR(v_saleinv.commission,'1234.59')||' ';
      :g_output := :g_output||TO_CHAR(v_totalcost,'123489.97')||CHR(10);
      :g_output := :g_output||TO_CHAR(v_saleinv.totalprice,'12345.45')||' ';

   END LOOP;

END IF;

EXCEPTION

 WHEN v_DEF THEN

  ROLLBACK WORK;

  :g_output := 'Such data does not exist.';

  WHEN OTHERS THEN

   ROLLBACK WORK;

   -- check error message
   :g_output := 'Error'||CHR(10);
   :g_output := :g_output||'Error code is '||SQLCODE||CHR(10);
   :g_output := :g_output||'Error message is '||SQLERRM;

  END;
   /
   PRINT g_output

【问题讨论】：

你需要一个GROUP BY someField 以及你有Count(*)的地方
@Ofisora - 仅当查询的投影包含一些非聚合列时。这不是这里的情况，所以不需要 GROUP BY。

标签： mysql sql oracle plsql

【解决方案1】：

这个错误最可能的原因是下面的选择

SELECT freightcost,totalcost
INTO  v_freightcost,v_totalcost
FROM car c, saleinv si
WHERE  c.serial = si.serial
AND   c.cname  = si.cname;

因为您要选择变量，所以选择只能返回一行。我假设您使用的序列号将从该选择返回多行。您需要确保它返回一个唯一的行。

【讨论】：

【解决方案2】：

下面的 SELECT INTO 语句只要求单数变量中的单数输出。您需要处理异常或修改代码，如果您期望更多输出然后使用 FOR LOOP。希望下面的 sn-p 有所帮助。

ACCEPT p_saleinv PROMPT 'Enter sales invoice number: '
VARIABLE g_output VARCHAR2(4000)
DECLARE
  v_ABC NUMBER(4);
  v_DEF EXCEPTION;
  v_freightcost car.freightcost%TYPE;
  v_totalcost car.totalcost%TYPE;
  CURSOR saleinvoicelist
  IS
    SELECT * FROM saleinv WHERE saleinv = '&p_saleinv';
BEGIN
  SELECT COUNT(*) INTO v_ABC FROM saleinv WHERE saleinv = '&p_saleinv';


  BEGIN
  SELECT freightcost,
    totalcost
  INTO v_freightcost,
    v_totalcost
  FROM car c,
    saleinv si
  WHERE c.serial = si.serial
  AND c.cname    = si.cname;
  EXCEPTION 
     WHEN TOO_MANY_ROWS THEN
  dbms_output.put_line('Too many rows fetched');
     RETURN;
     WHEN NO_DATA_FOUND THEN
  dbms_output.put_line('No rows fetched');
    RETURN;
  IF v_ABC       = '0' THEN
    RAISE v_DEF;
  ELSE
    FOR v_saleinv IN saleinvoicelist
    LOOP
      :g_output := :g_output||TRIM(v_saleinv.saleinv)||' ';
      :g_output := :g_output||TRIM(v_saleinv.cname)||' ';
      :g_output := :g_output||TRIM(v_saleinv.saledate)||' ';
      :g_output := :g_output||TRIM(v_saleinv.serial)||' ';
      :g_output := :g_output||TO_CHAR(v_freightcost,'122345.69')||CHR(10);
      :g_output := :g_output||TO_CHAR(v_saleinv.tax,'12345.99')||' ';
      :g_output := :g_output||TO_CHAR(v_saleinv.licfee,'123.76')||' ';
      :g_output := :g_output||TO_CHAR(v_saleinv.commission,'1234.59')||' ';
      :g_output := :g_output||TO_CHAR(v_totalcost,'123489.97')||CHR(10);
      :g_output := :g_output||TO_CHAR(v_saleinv.totalprice,'12345.45')||' ';
    END LOOP;
  END IF;
EXCEPTION
WHEN v_DEF THEN
  ROLLBACK WORK;
  :g_output := 'Such data does not exist.';
WHEN OTHERS THEN
  ROLLBACK WORK;
  -- check error message
  :g_output := 'Error'||CHR(10);
  :g_output := :g_output||'Error code is '||SQLCODE||CHR(10);
  :g_output := :g_output||'Error message is '||SQLERRM;
END;
/

【讨论】：