an error in ASP .NET4 + Linq - sql

Question

I'm working on a project that using ASP .NET 4 C# (with Linq) and SQL server. All run well open page on my own computer IIS and connect to local sql database. and it is ok if connection to server database with IIS from my computer. Error happen if open published page (of cause it run from server IIS and will connect to server database).
Error from server's event log is
Log Name: Application
Source: ASP.NET 4.0.30319.0
Date: 4/17/2015 1:33:11 PM
Event ID: 1309
Task Category: Web Event
Level: Warning
Keywords: Classic
User: N/A
Computer: SZHDB1.ds.jdsu.net
Description:
Event code: 3005
Event message: An unhandled exception has occurred.
Event time: 4/17/2015 1:33:11 PM
Event time (UTC): 4/17/2015 5:33:11 AM
Event ID: 89f5a478bff241d3aaa4798ce86ad707
Event sequence: 22
Event occurrence: 1
Event detail code: 0
Application information:
Application domain: /LM/W3SVC/1/ROOT/IMS-2-130737223782305527
Trust level: Full
Application Virtual Path: /IMS
Application Path: D:\WebSite\IMS\
Machine name: SZHDB1
Process information:
Process ID: 3944
Process name: w3wp.exe
Account name: IIS APPPOOL\ASP.NET v4.0
Exception information:
Exception type: UpdateException
Exception message: An error occurred while updating the entries. See the inner exception for details.
at System.Data.Mapping.Update.Internal.UpdateTranslator.Update(IEntityStateManager stateManager, IEntityAdapter adapter)
at System.Data.Objects.ObjectContext.SaveChanges(SaveOptions options)
at Log.set_storeLog(String value) in C:\Users\che57576\Documents\Visual Studio 2010\Projects\InstrManage\InstrManage\App\Common.cs:line 26
at InstrManage.Admin.Group.GridView_group_SelectedIndexChanged(Object sender, EventArgs e) in C:\Users\che57576\Documents\Visual Studio 2010\Projects\InstrManage\InstrManage\Admin\Group.aspx.cs:line 164
at System.Web.UI.WebControls.GridView.HandleEvent(EventArgs e, Boolean causesValidation, String validationGroup)
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
String or binary data would be truncated.
The statement has been terminated.
at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection)
at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning()
at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj)
at System.Data.SqlClient.SqlDataReader.ConsumeMetaData()
at System.Data.SqlClient.SqlDataReader.get_MetaData()
at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString)
at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async)
at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, DbAsyncResult result)
at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method)
at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior, String method)
at System.Data.SqlClient.SqlCommand.ExecuteDbDataReader(CommandBehavior behavior)
at System.Data.Mapping.Update.Internal.DynamicUpdateCommand.Execute(UpdateTranslator translator, EntityConnection connection, Dictionary2 identifierValues, List1 generatedValues)
at System.Data.Mapping.Update.Internal.UpdateTranslator.Update(IEntityStateManager stateManager, IEntityAdapter adapter)
and the related code are here:
'Common.cs':
public class Log
{
string conn, username;
public string storeLog
{
set
{
using (AdminEntities myEntrities = new AdminEntities(conn))
{
IMSlog log = new IMSlog();
log.user_name = username;
log.date_time = DateTimeOffset.Now;
log.what = value;
myEntrities.IMSlogs.AddObject(log);
myEntrities.SaveChanges(); //this is line 26
}
}
}
public Log(string linqConn,string userName)
{
conn = linqConn;
username = userName;
}
}
'Group.aspx.cs':
protected void Page_Load(object sender, EventArgs e)
{
log = new Log(sqlconnstr, Session["UserName"].ToString());
}
and in the same page, in the event:
protected void GridView_group_SelectedIndexChanged(object sender, EventArgs e)
{
bool result;
result = Int32.TryParse(GridView_group.SelectedRow.Cells[0].Text.ToString(), out index);
currentStatus = (GridView_group.SelectedRow.FindControl("CheckBox1") as CheckBox).Checked;
using (TransactionScope scope = new TransactionScope())
{
using (AdminEntities myEntrities = new AdminEntities(sqlconnstr))
{
admin_group c = (from r in myEntrities.admin_group
where r.group_id == index
select r).First();
c.group_enable = !currentStatus;
myEntrities.SaveChanges();
log.storeLog = "Set group ID " + index.ToString() + " to " + Convert.ToString(!currentStatus); // this is line 164
}
scope.Complete(); // To commit.
}
queryGroup();
}
when the above event be trigger, the error will happen.
I've search from lots of time, not sure why my laptop is ok but server cannot.
my laptop is win7 and sql express.
server is asp .net 4 and SQL server 2008.

Answer 1

The problem seems to be that you are trying to save a value too long for the length available in the database.
To find the problem, try to look at the length of the username you are trying to save and compare it to what's available in the database.
By setting a breakpoint on row #26 in Common.cs, you should be able to see the content of the variable username.
Once you find the problem, you can increase the size in your database. Also, it's recommended to validate the length of your username directly in your Web Application so the user can't enter a username too long for your database, an error message should be sent to the user asking him to use a shorter username.

Answer 2

One of the following assignments is too large for your data store
log.user_name = username;
log.date_time = DateTimeOffset.Now;
log.what = value;
You can also check if log.date_time is assigned the correct value