Question

日期变量未在存储过程中正确传递。此部分返回null

(CONVERT_TZ( (FROM_UNIXTIME(@fromDate/1000)),''UTC'', @timeZone) )AS startingDate, 
(CONVERT_TZ( (FROM_UNIXTIME(@toDate/1000)),''UTC'', @timeZone) ) AS endingDate,

这些日期显示为空

l1.started BETWEEN @startDate AND @endDate

我错过了这些值没有传递给查询

CREATE PROCEDURE reportFreeCoolingTrackerTest (
        IN fromDate varchar (50),
        IN toDate varchar (50),
        IN timeZone varchar (50))

    BEGIN
            DECLARE startDate varchar (50);
            DECLARE endDate varchar (50);
            DECLARE mylogID Int;

             SET startDate = FROM_UNIXTIME(fromDate/1000);
             SET endDate = FROM_UNIXTIME(toDate/1000);
             SET mylogID = (SELECT logID FROM logs l WHERE l.details LIKE 'FCT%');
             SET @tbl = CONCAT('log',mylogID);

 set @q1 = CONCAT('SELECT 
    i.details,l1.item31985,l1.item31987,
    ((l1.item31985 - l1.item31987)*(time_to_sec(timediff(t2.completed, l1.completed)))) / 3600  AS kwDifference,
    ((l1.item31985 - l1.item31987) *  (substr(l.details, instr(l.details , '':'' ) +1))) AS cost,
    (((l1.item31985 - l1.item31987) *  (substr(l.details, instr(l.details , '':'' ) +1)))
    *(time_to_sec(timediff(t2.completed, l1.completed)) / 3600)) AS costT,
      time_to_sec(timediff(t2.completed, l1.completed)) / 3600 AS coolingHours,
      time_to_sec(timediff(@endDate, @startDate)) / 3600 AS totalTimeRange,
    (CONVERT_TZ( (FROM_UNIXTIME(@fromDate/1000)),''UTC'', @timeZone) )AS startingDate, 
    (CONVERT_TZ( (FROM_UNIXTIME(@toDate/1000)),''UTC'', @timeZone) ) AS endingDate,DATABASE() AS databaseName,
     CASE
        when l1.activityId = t2.activityId THEN 1
        ELSE 0
    END AS errorCheck, t2.completed AS errorDay,a.scheduleType,@lgName,@mylogID  


  FROM logs l 
      INNER JOIN groups g ON g.groupId = l.groupId
      LEFT JOIN groups g1 ON g.parentId = g1.groupId
      LEFT JOIN groups g2 ON g1.parentId = g2.groupId
      LEFT JOIN groups g3 ON g2.parentId = g3.groupId                
      INNER JOIN activities a ON l.logId = a.logId 
      INNER JOIN  ',  @tbl,'  l1 ON a.activityId = l1.activityId ');

   set @q2 = CONCAT(@q1, 'INNER JOIN ', @tbl);

   SET @q3 = CONCAT(@q2, ' t2 ON t2.recordId = l1.recordid + 1
      INNER JOIN items i ON l.logId = i.logId AND i.name LIKE ''%KW%''
      INNER JOIN users u ON l1.userId = u.userId AND i.name LIKE ''%KW%''
     WHERE i.itemID = "31985"  AND  l1.activityId = 1257
      AND l1.started
        BETWEEN @startDate
            AND @endDate
     ORDER BY l1.recordId,l1.started');   

    PREPARE stmt FROM @q3;

     EXECUTE stmt;
  DEALLOCATE PREPARE stmt;
    END //

DELIMITER ;

Answer 1

您的代码存在许多问题。以下是主要内容：

您将过程输入参数和局部变量与用户（会话）变量混合在一起。例如。你有一个输入参数fromDate，但你在查询@fromDate中引用它是用户（会话）变量并且与参数无关。这就是为什么你得到NULL而不是实际值。
不是将查询字符串与变量值连接，而是将变量名称作为字符串文字的一部分。
在查询字符串中插入日期字符串文字（例如变量fromDate和startDate）时应引用它们。同样适用于timeZone值。
在您的查询字符串中，您指的是@lgName变量，该变量很可能不包含任何值。即使它确实然后通过用户（会话）变量传递它，你应该通过另一个过程参数完成它。
这部分
```
SET mylogID = (SELECT logID FROM logs l WHERE l.details LIKE 'FCT%');
```
应返回唯一的值，否则会破坏您的代码。使用LIKE可以轻松生成多行。这就是说应用LIMIT 1（或聚合函数，例如MIN()或MAX）或使用基于具有（具有）PK或{的列的条件重写它{1}}约束。
UNIQE，fromDate，startDate是局部变量。但由于某种原因，您使用用户变量mylogID来保存表名值。抛弃它，只需在构建查询字符串时连接@tbl和'log'值。

据说你的程序看起来像

mylogID

这是 SQLFiddle 演示，显示最终查询字符串而不是执行它

变量未将正确或任何数据传递给查询

1 个答案: