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
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。
其他回答
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
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。
扩展Kon的代码来帮助调试存储过程:
private void ExtractSqlCommandForDebugging(SqlCommand cmd)
{
string sql = "exec " + cmd.CommandText;
bool first = true;
foreach (SqlParameter p in cmd.Parameters)
{
string value = ((p.Value == DBNull.Value) ? "null"
: (p.Value is string) ? "'" + p.Value + "'"
: p.Value.ToString());
if (first)
{
sql += string.Format(" {0}={1}", p.ParameterName, value);
first = false;
}
else
{
sql += string.Format("\n , {0}={1}", p.ParameterName, value);
}
}
sql += "\nGO";
Debug.WriteLine(sql);
}
在我的第一个测试用例中，它生成:
exec dbo.MyStoredProcName @SnailMail=False
, @Email=True
, @AcceptSnailMail=False
, @AcceptEmail=False
, @DistanceMiles=-1
, @DistanceLocationList=''
, @ExcludeDissatisfied=True
, @ExcludeCodeRed=True
, @MinAge=null
, @MaxAge=18
, @GenderTypeID=-1
, @NewThisYear=-1
, @RegisteredThisYear=-1
, @FormersTermGroupList=''
, @RegistrationStartDate=null
, @RegistrationEndDate=null
, @DivisionList='25'
, @LocationList='29,30'
, @OneOnOneOPL=-1
, @JumpStart=-1
, @SmallGroup=-1
, @PurchasedEAP=-1
, @RedeemedEAP=-1
, @ReturnPlanYes=False
, @MinNetPromoter=-1
, @MinSurveyScore=-1
, @VIPExclusionTypes='-2'
, @FieldSelectionMask=65011584
, @DisplayType=0
GO
你可能需要添加一些有条件的“..is…”类型的赋值，例如日期和时间。
一个衬套:
string.Join(",", from SqlParameter p in cmd.Parameters select p.ToString())
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
