我收到错误＆＃34;转换nvarchar值时转换失败＆＃39; MISCELLANEOUS＆＃39;数据类型int＆＃34;当我使用group by子句时

Question

当我运行以下SQL语句时：

SELECT 
    timecollected, SUM(waitingtaskscounttotal) waitingtaskscounttotal 
FROM 
    (SELECT 
         timecollected, CAST(raw_value AS INT) AS waitingtaskscounttotal
     FROM 
         spotlight_perfdata sp
     JOIN 
         spotlight_stat_names sn ON sp.statistic_name_id = sn.statistic_name_id
                                 AND sn.statistic_class_id = CONVERT(NVARCHAR, @statistic_class_id)
     WHERE 
         sp.statistic_class_id = CONVERT(NVARCHAR, @statistic_class_id)
         AND (sp.timecollected >= convert(NVARCHAR, @firstdate, 126)
              AND sp.timecollected <= convert(NVARCHAR, @lastdate, 126))
         AND sp.monitored_object_id = CONVERT(NVARCHAR, @monitored_object_id)
         AND sn.statistic_name = 'waitingtaskscounttotal') TableA
GROUP BY 
    timecollected
ORDER BY 
    timecollected DESC

我收到错误：

  

转换nvarchar值时转换失败＆＃39; MISCELLANEOUS＆＃39;数据类型int。

但是在我从SQL语句中删除了列timecollected之后，它起作用了：

SELECT 
    SUM(waitingtaskscounttotal) waitingtaskscounttotal 
FROM 
    (SELECT 
         timecollected, CAST(raw_value AS INT) AS waitingtaskscounttotal
     FROM 
         spotlight_perfdata sp
     JOIN 
         spotlight_stat_names sn ON sp.statistic_name_id = sn.statistic_name_id
                                 AND sn.statistic_class_id = CONVERT(NVARCHAR, @statistic_class_id)
     WHERE 
         sp.statistic_class_id = CONVERT(NVARCHAR, @statistic_class_id)
         AND (sp.timecollected >= convert(NVARCHAR, @firstdate, 126)
              AND sp.timecollected <= convert(NVARCHAR, @lastdate, 126))
         AND sp.monitored_object_id = CONVERT(NVARCHAR, @monitored_object_id)
         AND sn.statistic_name = 'waitingtaskscounttotal') TableA

我无法弄清楚它有什么问题。

Answer 1

改变这个：

CAST(raw_value AS INT)

到此：

CASE 
WHEN raw_value like '%[0-9]%' and not raw_value like '%[^0-9]%' 
OR raw_value like '-%[0-9]%' and not raw_value like '-%[^0-9]%' 
THEN CAST(raw_value AS int)
ELSE NULL
END

这将使一切不是int NULL

Answer 2

为避免此问题，我将where子句筛选出的数据保存到临时表中，然后进行int转换。