我有一个大数据表.该表中有1000万条记录.
这个查询的最佳方法是什么?
Delete LargeTable where readTime < dateadd(MONTH,-7,GETDATE())
Run Code Online (Sandbox Code Playgroud) 我尝试通过if-else条件在mvc控制器中显示一个警告框.但是没有显示警告框.我的错误是什么?
调节器
public ActionResult Index()
{
int userId = Convert.ToInt32(Session["userId"].ToString());
if (WebMatrix.WebData.WebSecurity.IsAuthenticated)
{
if (userId == 90043)
{
return View();
}
else
{
TempData["Message"] = "You are not authorized.";
return RedirectToAction("Index", "Home");
}
}
else
{
return RedirectToAction("Index", "Home");
}
}
Run Code Online (Sandbox Code Playgroud) 我试图在控制器中获取客户端IP地址.它工作,但有时我得到这个错误:
The underlying connection was closed: An unexpected error occurred on a receive
String IP = "";
using (WebResponse response = request.GetResponse())
{
using (StreamReader stream = new StreamReader(response.GetResponseStream()))
{
IP = stream.ReadToEnd();
}
}
int first = IP.IndexOf("Address: ") + 9;
int last = IP.LastIndexOf("</body>");
IP = IP.Substring(first, last - first);
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获取客户端IP地址有什么不同的方法吗?
当我执行查询时
Select * from TableName
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我收到此错误:
在页面(1:4796)上的数据库'MYDABATADASE'(ID:5)中进行内部操作期间检测到不一致。请联系技术支持。参考编号7。
如何解决此错误?
我尝试将数据从DB1复制到DB2.但是我得到错误:必须声明表变量"@TableName".
这段代码有什么问题?
功能:
public void TransferData()
{
SqlConnection source = new SqlConnection(strConnectDB1);
SqlConnection destination = new SqlConnection(strConnectDB2);
source.Open();
destination.Open();
SqlCommand cmd= new SqlCommand("SELECT * FROM @TableName", source);
cmd.Parameters.AddWithValue("@TableName", listbox1.SelectedItem.ToString());
SqlDataReader reader = cmd.ExecuteReader();
SqlBulkCopy bulkData = new SqlBulkCopy(destination);
bulkData.DestinationTableName = listbox1.SelectedItem.ToString();
bulkData.WriteToServer(reader);
.
.
}
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按钮:
private void button5_Click(object sender, EventArgs e)
{
CreateTableName();
TransferData();
}
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