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();
}
其他回答
如果你要转换命令文本:
Private Function ConvToNonParm(ByRef Cmd As SqlClient.SqlCommand) As String
For myCnt As Int16 = 1 To Cmd.Parameters.Count
Dim myVal As String = Cmd.Parameters(myCnt - 1).Value
Select Case Cmd.Parameters(myCnt - 1).SqlDbType
Case SqlDbType.Char, SqlDbType.NChar, SqlDbType.VarChar, SqlDbType.NChar, SqlDbType.NVarChar 'and so on
myVal = "'" & myVal & "'"
'Case "others...."
Case Else
'please assing
End Select
Cmd.CommandText = Replace(Cmd.CommandText, Cmd.Parameters(myCnt - 1).ToString, myVal)
Next
Cmd.Parameters.Clear()
Return Cmd.CommandText
End Function
现在你可以像下面这样获得非参数commandtext:
myCmd.CommandText = "UPDATE someTable SET Value = @Value"
myCmd.CommandText &= " WHERE Id = @Id"
myCmd.Parameters.AddWithValue("@Id", 1234)
myCmd.Parameters.AddWithValue("@Value", "myValue")
myCmd.CommandText = ConvToNonParm(myCmd)
结果是“更新someTable SET值= 'myValue' WHERE Id = 1234”，不再带参数
//For Oracle db in the sql text the parameters could be like :ID,:NAME etc.
//This is same as above Seyed Hossein Mirheydari, but slightly improved,
//this works with parameter names well.
//Further is straight simple one, you need to format for datatypes
//after query is generated.
private string GetFullOraQuery(OracleCommand cmd)
{
string query = cmd.CommandText;
foreach (OracleParameter p in cmd.Parameters)
{
query = query.Replace(":" + p.ParameterName, ((p.Value == null) ? "" : p.Value.ToString()));
}
return query;
}
如果你正在使用SQL Server，你可以使用SQL Server Profiler(如果你有的话)来查看实际执行的命令字符串。这对于复制/粘贴测试很有用，但对于日志记录恐怕就没用了。
我的解决方案:
public static class DbHelper
{
public static string ToString(this DbParameterCollection parameters, string sqlQuery)
{
return parameters.Cast<DbParameter>().Aggregate(sqlQuery, (current, p) => current.Replace(p.ParameterName, p.Value.ToString()));
}
}
不能，因为它不会生成任何SQL。
参数化的查询(CommandText中的那个)作为准备好的语句被发送到SQL Server。执行命令时，参数和查询文本是分开处理的。在任何时间点都不会生成完整的SQL字符串。
您可以使用SQL Profiler来查看幕后操作。
