Question

我正在开发一个项目，允许用户仅通过选择列来构建查询。

我的应用程序似乎工作正常并生成正确的查询。但是当我执行查询时，我得到以下异常

专栏＆＃39; Tasks.Duration＆＃39;在选择列表中无效，因为它是不包含在聚合函数或GROUP BY子句中。

这里没有做的是我的查询实际上包含了正确的GROUP BY语句

以下是我的应用程序生成的查询

SELECT
 [Campaign].[Title] AS [CampaignTitle]
,CASE WHEN [Task].[Duration] <= @p0 THEN @p1 WHEN [Task].[Duration] >= @p2 AND [Task].[Duration] <= @p3 THEN @p4 ELSE @p5 END AS [9pl1WbY1ZkSvSpel3g4xmw]
,COUNT(1) AS [Ib7ZS4arHkSUWhf4saEtmg]
,SUM(CASE WHEN [Task].[Duration] <= @p6 THEN @p7 ELSE @p8 END) AS [xW1GmttC6kWHsc9QIEPN9w]
FROM [Tasks] AS [Task]
INNER JOIN [Campaigns] AS [Campaign] ON [Campaign].[Id] = [Task].[CampaignId]
INNER JOIN [Users] AS [User] ON [User].[Id] = [Task].[CompletedBy]
INNER JOIN [Results] AS [Result] ON [Result].[Id] = [Task].[ResultId]
WHERE
[Result].[IsCompleted] = @p9 AND ( [User].[LastName] = @p10 OR [User].[LastName] = @p11 )
GROUP BY
[Campaign].[Title]
,CASE WHEN [Task].[Duration] <= @p13 THEN @p14 WHEN [Task].[Duration] >= @p15 AND [Task].[Duration] <= @p16 THEN @p17 ELSE @p18 END
HAVING
COUNT(1) >= @p12
ORDER BY
 [Campaign].[Title]
,CASE WHEN [Task].[Duration] <= @p19 THEN @p20 WHEN [Task].[Duration] >= @p21 AND [Task].[Duration] <= @p22 THEN @p23 ELSE @p24 END

更好的是，我尝试用参数值手动替换参数名称。然后我把它们输出查询并在SSMS中执行它并且它没有任何问题。

这就是我执行查询的方式

using (SqlConnection connection = new SqlConnection(this.connectionString))
using (SqlDataAdapter sqlAdapter = new SqlDataAdapter(selectCommand))
{
    try
    {
        selectCommand.Connection = connection;

        DataTable table = new DataTable();

        sqlAdapter.Fill(table);

        return table;
    }
    catch (Exception e)
    {
        throw new ReportException(string.Format("{0} {1}", e.Message, e.GetType().FullName));
    }
}

以下是我用于将参数替换为值

的方法

private string GetPlainQuery(SqlCommand selectCommand)
{
    string output = selectCommand.CommandText;

    for (int i = selectCommand.Parameters.Count - 1; i >= 0; i--)
    {
        var p = selectCommand.Parameters[i];

        string value = p.Value.ToString();

        if (p.SqlDbType == SqlDbType.NChar || p.SqlDbType == SqlDbType.NText || p.SqlDbType == SqlDbType.NVarChar || p.SqlDbType == SqlDbType.Text || p.SqlDbType == SqlDbType.Char || p.SqlDbType == SqlDbType.Date || p.SqlDbType == SqlDbType.DateTime || p.SqlDbType == SqlDbType.SmallDateTime)
        {
            value = string.Format("'{0}'", value.Replace("'", "''"));
        }

        output = output.Replace(p.ParameterName, value);
    }

    return output;
}

导致此错误的原因是什么？我该如何解决？

已更新

这是我用值

替换参数后的查询

SELECT
 [Campaign].[Title] AS [CampaignTitle]
,CASE WHEN [Task].[Duration] <= 100 THEN '<100' WHEN [Task].[Duration] >= 100 AND [Task].[Duration] <= 200 THEN 'BETWEEN 100 AND 200' ELSE '>200' END AS [9pl1WbY1ZkSvSpel3g4xmw]
,COUNT(1) AS [Ib7ZS4arHkSUWhf4saEtmg]
,SUM(CASE WHEN [Task].[Duration] <= 100 THEN 1 ELSE 0 END) AS [xW1GmttC6kWHsc9QIEPN9w]
FROM [Tasks] AS [Task]
INNER JOIN [Campaigns] AS [Campaign] ON [Campaign].[Id] = [Task].[CampaignId]
INNER JOIN [Users] AS [User] ON [User].[Id] = [Task].[CompletedBy]
INNER JOIN [Results] AS [Result] ON [Result].[Id] = [Task].[ResultId]
WHERE
[Result].[IsCompleted] = 1 AND ( [User].[LastName] = 'Yo' OR [User].[LastName] = 'Smith' )
GROUP BY
 [Campaign].[Title]
,CASE WHEN [Task].[Duration] <= 100 THEN '<100' WHEN [Task].[Duration] >= 100 AND [Task].[Duration] <= 200 THEN 'BETWEEN 100 AND 200' ELSE '>200' END
HAVING
COUNT(1) >= 0
ORDER BY
 [Campaign].[Title]
,CASE WHEN [Task].[Duration] <= 100 THEN '<100' WHEN [Task].[Duration] >= 100 AND [Task].[Duration] <= 200 THEN 'BETWEEN 100 AND 200' ELSE '>200' END

Answer 1

我的猜测是错误是由于您在选择列表中的case语句与组中的case语句不同。我通常做的是在子查询中解析这些列，以便更容易阅读和维护外部查询。

Answer 2

我在这里缺少的是框架将在替换参数之前首先验证它们的查询。

由于参数名称在select和group by中不同，因此框架假设它们具有导致问题的不同值。

解决方案是重用相同的参数名称，以使框架保证值相同。

尝试使用c＃

2 个答案: