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2025-03-04 07:00:04

从SqlCommand对象获取生成的SQL语句?

我有以下代码:

Using cmd As SqlCommand = Connection.CreateCommand
    cmd.CommandText = "UPDATE someTable SET Value = @Value"
    cmd.CommandText &= " WHERE Id = @Id"
    cmd.Parameters.AddWithValue("@Id", 1234)
    cmd.Parameters.AddWithValue("@Value", "myValue")
    cmd.ExecuteNonQuery
End Using

我想知道是否有任何方法来获得最终的SQL语句作为字符串，它应该看起来像这样:

UPDATE someTable SET Value = "myValue" WHERE Id = 1234

如果有人想知道我为什么要这么做

用于记录(失败的)语句 可以将其复制粘贴到企业管理器中进行测试

当前回答

这个方法是我自己写的。我用了布鲁诺·拉尼克的代码。也许它对某人有用。

 public static string getQueryFromCommand(SqlCommand cmd)
    {
        StringBuilder CommandTxt = new StringBuilder();
        CommandTxt.Append("DECLARE ");
        List<string> paramlst = new List<string>();
        foreach (SqlParameter parms in cmd.Parameters)
        {
            paramlst.Add(parms.ParameterName);
            CommandTxt.Append(parms.ParameterName + " AS ");
            CommandTxt.Append(parms.SqlDbType.ToString());
            CommandTxt.Append(",");
        }

        if (CommandTxt.ToString().Substring(CommandTxt.Length-1, 1) == ",")
            CommandTxt.Remove(CommandTxt.Length-1, 1);
        CommandTxt.AppendLine();
        int rownr = 0;
        foreach (SqlParameter parms in cmd.Parameters)
        {
            string val = String.Empty;
            if (parms.DbType.Equals(DbType.String) || parms.DbType.Equals(DbType.DateTime))
                val = "'" + Convert.ToString(parms.Value).Replace(@"\", @"\\").Replace("'", @"\'") + "'";
            if (parms.DbType.Equals(DbType.Int16) || parms.DbType.Equals(DbType.Int32) || parms.DbType.Equals(DbType.Int64) || parms.DbType.Equals(DbType.Decimal) || parms.DbType.Equals(DbType.Double))
                val = Convert.ToString(parms.Value);

            CommandTxt.AppendLine();
            CommandTxt.Append("SET " + paramlst[rownr].ToString() + " = " + val.ToString());
            rownr += 1;
        }
        CommandTxt.AppendLine();
        CommandTxt.AppendLine();
        CommandTxt.Append(cmd.CommandText);
        return CommandTxt.ToString();
    }
2017-07-28 16:20:30

其他回答

我也有同样的问题，在阅读了这些回复后，我错误地认为不可能得到准确的结果查询。我错了。

解决方案: 在SQL Server Management Studio中打开活动监视器，将进程部分缩小为应用程序在连接字符串中使用的登录用户名、数据库或应用程序名称。当调用db刷新活动监视器时。当您看到流程时，右键单击它并查看详细信息。

注意，对于繁忙的db来说，这可能不是一个可行的选项。但是您应该能够使用这些步骤大大缩小结果。

2014-02-21 15:47:01

这个方法现在对我很有效。也许它对某人有用。请原谅所有的冗余。

    Public Shared Function SqlString(ByVal cmd As SqlCommand) As String
    Dim sbRetVal As New System.Text.StringBuilder()
    For Each item As SqlParameter In cmd.Parameters
        Select Case item.DbType
            Case DbType.String
                sbRetVal.AppendFormat("DECLARE {0} AS VARCHAR(255)", item.ParameterName)
                sbRetVal.AppendLine()
                sbRetVal.AppendFormat("SET {0} = '{1}'", item.ParameterName, item.Value)
                sbRetVal.AppendLine()

            Case DbType.DateTime
                sbRetVal.AppendFormat("DECLARE {0} AS DATETIME", item.ParameterName)
                sbRetVal.AppendLine()
                sbRetVal.AppendFormat("SET {0} = '{1}'", item.ParameterName, item.Value)
                sbRetVal.AppendLine()

            Case DbType.Guid
                sbRetVal.AppendFormat("DECLARE {0} AS UNIQUEIDENTIFIER", item.ParameterName)
                sbRetVal.AppendLine()
                sbRetVal.AppendFormat("SET {0} = '{1}'", item.ParameterName, item.Value)
                sbRetVal.AppendLine()

            Case DbType.Int32
                sbRetVal.AppendFormat("DECLARE {0} AS int", item.ParameterName)
                sbRetVal.AppendLine()
                sbRetVal.AppendFormat("SET {0} = {1}", item.ParameterName, item.Value)
                sbRetVal.AppendLine()

            Case Else
                Stop

        End Select
    Next

    sbRetVal.AppendLine("")
    sbRetVal.AppendLine(cmd.CommandText)

    Return sbRetVal.ToString()
End Function
2011-04-06 08:45:03

从参数命令到非参数命令，可以修改

Using cmd As SqlCommand = Connection.CreateCommand
    cmd.CommandText = "UPDATE someTable SET Value = @Value"
    cmd.CommandText &= " WHERE Id = @Id"
    cmd.Parameters.AddWithValue("@Id", 1234)
    cmd.Parameters.AddWithValue("@Value", "myValue")
    cmd.ExecuteNonQuery
End Using

To

Private sub Update( byval myID as Int32, byval myVal as String)
    Using cmd As SqlCommand = Connection.CreateCommand
        cmd.CommandText = "UPDATE someTable SET Value = '" & myVaL & "'" & _
                          " WHERE Id = " & myID  
        cmd.ExecuteNonQuery
    End Using
End sub
2019-09-04 00:15:59

也需要覆盖非存储过程，所以我用以下逻辑扩充了CommandAsSql库(见上面@Flapper的回答下的评论):

    private static void CommandAsSql_Text(this SqlCommand command, System.Text.StringBuilder sql)
    {
        string query = command.CommandText;

        foreach (SqlParameter p in command.Parameters)
            query = Regex.Replace(query, "\\B" + p.ParameterName + "\\b", p.ParameterValueForSQL()); //the first one is \B, the 2nd one is \b, since ParameterName starts with @ which is a non-word character in RegEx (see https://stackoverflow.com/a/2544661)

        sql.AppendLine(query);
    }

pull请求在: https://github.com/jphellemons/CommandAsSql/pull/3/commits/527d696dc6055c5bcf858b9700b83dc863f04896

Regex的想法是基于@stambikk和EvZ上面的评论，以及https://stackoverflow.com/a/2544661/903783的“更新:”部分提到了“消极的事后判断”。在正则表达式的开头使用\B而不是\B来进行单词边界检测是因为p.parameterName总是以“@”开头，而“@”不是单词字符。

注意ParameterValueForSQL()是CommandAsSql库中定义的一个扩展方法，用于处理单引号字符串参数值等问题。

2018-09-19 15:58:06

sql命令查询将通过exec sp_executesql执行，所以这里有另一种方法来获取语句作为字符串(SqlCommand扩展方法):

public static string ToSqlStatement(this SqlCommand cmd)
{
    return $@"EXECUTE sp_executesql N'{cmd.CommandText.Replace("'", "''")}'{cmd.Parameters.ToSqlParameters()}";
}

private static string ToSqlParameters(this SqlParameterCollection col)
{
    if (col.Count == 0)
        return string.Empty;
    var parameters = new List<string>();
    var parameterValues = new List<string>();
    foreach (SqlParameter param in col)
    {
        parameters.Add($"{param.ParameterName}{param.ToSqlParameterType()}");
        parameterValues.Add($"{param.ParameterName} = {param.ToSqlParameterValue()}");
    }
    return $",N\'{string.Join(",", parameters)}\',{string.Join(",", parameterValues)}";
}

private static object ToSqlParameterType(this SqlParameter param)
{
    var paramDbType = param.SqlDbType.ToString().ToLower();
    if (param.Precision != 0 && param.Scale != 0)
        return $"{paramDbType}({param.Precision},{param.Scale})";
    if (param.Precision != 0)
        return $"{paramDbType}({param.Precision})";
    switch (param.SqlDbType)
    {
        case SqlDbType.VarChar:
        case SqlDbType.NVarChar:
            string s = param.SqlValue?.ToString() ?? string.Empty;
            return paramDbType + (s.Length > 0 ? $"({s.Length})" : string.Empty);
        default:
            return paramDbType;
    }
}

private static string ToSqlParameterValue(this SqlParameter param)
{
    switch (param.SqlDbType)
    {
        case SqlDbType.Char:
        case SqlDbType.Date:
        case SqlDbType.DateTime:
        case SqlDbType.DateTime2:
        case SqlDbType.DateTimeOffset:
        case SqlDbType.NChar:
        case SqlDbType.NText:
        case SqlDbType.NVarChar:
        case SqlDbType.Text:
        case SqlDbType.Time:
        case SqlDbType.VarChar:
        case SqlDbType.Xml:
            return $"\'{param.SqlValue.ToString().Replace("'", "''")}\'";
        case SqlDbType.Bit:
            return param.SqlValue.ToBooleanOrDefault() ? "1" : "0";
        default:
            return param.SqlValue.ToString().Replace("'", "''");
    }
}

public static bool ToBooleanOrDefault(this object o, bool defaultValue = false)
{
    if (o == null)
        return defaultValue;
    string value = o.ToString().ToLower();
    switch (value)
    {
        case "yes":
        case "true":
        case "ok":
        case "y":
            return true;
        case "no":
        case "false":
        case "n":
            return false;
        default:
            bool b;
            if (bool.TryParse(o.ToString(), out b))
                return b;
            break;
    }
    return defaultValue;
}
2016-12-06 10:43:40

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