Linq DateTime.UtcNow and SQL DateTime Datatype

By -

Recently I have being using SQLMetal that generates dbml and the backing code. I encountered a problem that was obtuse, apparently good code was failing to execute. The message from Linq was "Row not found or changed".

 

Launching SQL Profiler showed me the SQL

 

exec sp_executesql N'UPDATE [WebApp].[OperationInfo]
SET [WorkflowResultsID] = @p8
WHERE ([MachineVersionID] = @p0) AND ([OperationID] = @p1) 
AND ([ExecutionDate] = @p2) AND ([OperationType] = @p3) AND ([WorkflowResultsID] IS NULL) 
AND ([ConfigurationResultsID] IS NULL) AND 
([SequenceResultsID] IS NULL) AND ([ExecutionGuids] IS NULL)
 AND ([WorkRequestID] IS NULL) AND ([LastStep] = @p4) AND ([TrafficRuleCommitStatus] = @p5) 
 AND ([CreatedUTC] = @p6) AND ([LastModifiedUTC] = @p7)',
 N'@p0 bigint,@p1 bigint,@p2 datetime,@p3 smallint,@p4 varchar(12),@p5 smallint,@p6 datetime,@p7 datetime,@p8 bigint',@p0=1,@p1=6,@p2='2010-08-05 09:56:47.2470000',@p3=1,@p4='Requirements',@p5=0,@p6='2010-08-05 09:56:47.2470000',@p7='2010-08-05 09:56:47.2470000',@p8=3

Manually executing, I got:

 

Msg 241, Level 16, State 1, Line 4

Conversion failed when converting date and/or time from character string.

 

Looking at the TSQL, I said huh???!!!???

 

I then tried an experiment.

 

Declare @p2 datetime

set @p2='2010-08-05 09:56:47'

set @p2='2010-08-05 09:56:47.247'

set @p2='2010-08-05 09:56:47.2470'

set @p2='2010-08-05 09:56:47.24700'

set @p2='2010-08-05 09:56:47.247000'

set @p2='2010-08-05 09:56:47.2470000'

The red ones gave the above error messages.

 

Tried it with:

 

Declare @p2 datetimeoffset

set @p2='2010-08-05 09:56:47'

set @p2='2010-08-05 09:56:47.247'

set @p2='2010-08-05 09:56:47.2470'

set @p2='2010-08-05 09:56:47.24700'

set @p2='2010-08-05 09:56:47.247000'

set @p2='2010-08-05 09:56:47.2470000'

Set @p2='2010-08-05 09:56:47.2470000'

Set @p2='2010-08-05 09:56:47.2470000'

Everything worked....

then with


Declare @p2 datetime2

set @p2='2010-08-05 09:56:47'

set @p2='2010-08-05 09:56:47.247'

set @p2='2010-08-05 09:56:47.2470'

set @p2='2010-08-05 09:56:47.24700'

set @p2='2010-08-05 09:56:47.247000'

set @p2='2010-08-05 09:56:47.2470000'

Set @p2='2010-08-05 09:56:47.2470000'

Set @p2='2010-08-05 09:56:47.2470000'

Everything worked....

 

In the C# code, I had changed the code from

 

OperationInfo.CreatedUTC=DateTime.Now;

 

to

 

OperationInfo.CreatedUTC=DateTime.UtcNow;

 

This change was causing the problem!

 

The solutions are

  • OperationInfo.CreatedUTC=DateTime.Now.ToUniversalTime();
  • Changing the database column types.

Comments

Post a Comment

Popular posts from this blog

Simple WP7 Mango App for Background Tasks, Toast, and Tiles: Code Explanation

By -
Image
This is a continuation of this post , explaining how the sample app works. Caution : This sample isn’t meant as an example of best patterns and practices. If you see something in the code you would never do, then don’t. Solution File Organization The app has three Visual Studio Projects: the app, the agent, and the shared code library between them. One of the great things about Mango is that now the built-in Visual Studio Unit test functionality is available. By separating out the meat of the work into the SampleShared project, I can also focus my unit testing there. SampleApp1 The app has a MainPage, a ViewModel, and the WMAppManifest.xml file modified to note my ExtendedTask of BackgroundServiceAgent. The Agent is extremely simple with a call to the shared library, an update to the Tile, and a call to pop up Toast. The meat of the work is in the SampleShared library. The AgentMgr manages the background agent : add, remove, find, run now. It is only called f
Read more

Yet once more into the breech (of altered programming logic)

By -
Once upon a time, long long ago, I wrote 8-bit programs in Tiny-C with absolute addressing being the only reality.  Then we had Borland Turbo-C with relative addresses and the joys of relative assembly jumps. Enter Windows and the joys of locking and unlocking memory blocks that you must allocated and manage yourself. Then came Visual Basic which evolved into .Net CLR and decreasing awareness of what is happening under the hood.   With VS2010 including F# and enhanced parallelism in .Net4, we actually have to go retro a bit – back to the world of having to understand the hardware. CPU speeds are no longer increasing – I have an old laptop from six+ years ago that ran at 3.2 GHz. This year I updated one of my machines off-the-shelf from Costco.com, an I7-920 with 4 cores and hyper-threading (8 CPUs appears in Task Manager) and 12 GB of DDR3 RAM. This week I ordered from Costco a Phenom II X6 (Yes – 6 REAL CORES) for one of my daughters.  This CPU will (according to YouTube demos) o
Read more

How to convert SVG data to a Png Image file Using InkScape

By -
Image
Introduction The project required the need to put the visual pie chart on a web page on the client and in a Pdf file created on the server. I eventually choose to use a Telerik Kendo DataViz Chart control on the client, and use a PNG file on the server for the Pdf file. This blog post will explain the process and code to convert the client-side pie chart Svg data to a Png file, and provide a download to the working code. Prerequisites You need to have a trial version of the Telerik Kendo library installed in order to make the sample code work. You also need InkScape installed. InkScape is the application that does the actual conversion. You will need to change the Web.config appSetting of “ExeDirectoryForInkscape” to represent your own installation location. Any SVG Data Will Work The pie chart was created using the Telerik Kendo DataViz chart control. While I name a specific control, as long as you have access to the SVG data, the same conversion process on the server will
Read more