C# - Entity Framework - Update Field Value To Current DB Server Time?
Dec 9, 2010
I've pulling back an entity object from a database and I need to update the date to the DB server's date/time - usually you could accomplish this by setting it with the SQL getDate() function.
How can I accomplish this in the following scenario:
var client = context.client.Where(c=>c.clientID == 1).FirstOrDefault();
// the value needs to be the value of the server's current date, i.e, getDate()... not DateTime.Now
client.someDate = <somevalue>;
context.SaveChanges();
I have an EDM, it includes the entities extension and history. My goal is to use history to keep track of all the changes made to extension entity. For example, if extension with ID 223 has its property 'Name_Display' changed - I want the history entity to record this.
I'm using ASP.NET with VB.NET. Where in my code do I put the hook to say, "update the history entity" and what should that hook look like?
I am mapping a stored procedure to an entity by right clicking on the entity (in the .edmx) and selecting "Stored Procedure Mapping." This brings you to a Mapping Details - "Name of Entity" Window that allows you to select the insert, update, and delete stored procedures associated with the Entity. It also maps the stored procedure parameter to the Entity "Property" (Column).
I'm gettin an error "error 2042: Parameter Mapping specified is not valid." The cause of the error is fairly obvious, in the Insert stored procedure that has been selected, a 'CHAR' parameter is being mapped to an Int32 Entity Property. I altered the stored procedure parameter to match the entity, I deleted the stored procedure, readded, and reslected it as the Insert function. I also cleaned, validated, updated model from database. No matter what I do, the parameter list in the mapping details doesn't reflect the change to the stored procedure. It's stuck on a char --> int32 mapping, even though it has been changed, like it's buried deep in meta data some where.
I'm writing a custom .NET MembershipProvider (not the built in one) and trying to update using Entity Framework. But of course i have no access to (Try)UpdateModel. How can i update it?
I have a date/time stored in a smalldatetime field (ms sql 2005) that i want to compare with the current time and receive a difference. If the difference is less than 30 minutes, do this....if more do that....
How can I give set foreign key value field in Entity Framework. I have Kartlar entity (related from kartlar table). I need simple save method this field but, RehberID, KAmpanyaId,BirimID is foregin Key....
public static class SatisServicesUpdateTables { public static void SaveKartlar(int RehberID, int KampanyaID, int BrimID) { using (GenSatisModuleEntities genSatisKampanyaCtx = new GenSatisModuleEntities()) { Kartlar kartlar = new Kartlar(); kartlar.RehberReference.EntityKey = new System.Data.EntityKey("genSatisKampanyaCtx.Rehber", "ID", RehberID); kartlar.KampanyaReference.EntityKey = new System.Data.EntityKey("genSatisKampanyaCtx.Kampanya", "ID", KampanyaID); kartlar.BirimReference.EntityKey = new System.Data.EntityKey("genSatisKampanyaCtx.Birim", "ID", BrimID); kartlar.Notlar = "hfhfhfhfhfhfghfghfgfghk"; genSatisKampanyaCtx.AddToKartlar(kartlar); genSatisKampanyaCtx.SaveChanges(); } } }
But it throws to me : ArgumentException was unhandled by user code link text
I have been updating my Entity Framework by simply right clicking and clicking on "update model from database". I usually go under the "Add" tab and then click the tables and click finish. I also use "refresh" sometimes as well. What are the differences between these? and also when I do refresh or add sometimes the entity comes out wrong or keeps some of the old information in cache, how can I just get the entity to match my database and clean out any of the old cached things.
I have a few entities I'd like to update at the same time. However I'd like to write individual update methods in each classes partial class file, for each entity and call them all at the same time. For example:
public sub UpdateEntity1() ... end sub
public sub UpdateEntity2() ... end sub
public sub UpdateEntity3() ... end sub
public sub UpdateAll() UpdateEntity1() UpdateEntity2() UpdateEntity3() end sub
My question is how do I manage the object context? do I create one object context in the class I'm calling UpdateAll(), then pass it as a parameter to each individual update method? Or do I create a new context for each Update? I'd like to use the same context because the object are related, and this would decrease the db calls to update all the records.
But, name may not have changed, it may only be a change to the content textbox.
The problem is that entity framework treats Name as changed just because I've set it's value, regardless of whether I've set exactly the same value or not.
Ideally, I would like EF to only mark things as changed if they genuinely have changed.
How should I solve simulation update, when one user updates already updated entery by another user?
First user request 'Category' entityobject, second user does the same. Second user updates this object and first user updates. I have field timestamp field in database that wa set to Concurrency Mode - Fixed.
How do I use a stored procedure to change one or more (but not all) fields of a entity in EF4? I have a stored procedure "ChangePassword" taking a username and and a password as parameters and a User entity containing properties for Username and Password as well as other properties. I want to be able to use this stored procedure from a function to update the password from a function in one of my repositories. How to do this?
I have read some articles about the new enitity framework and I think it looks very cool from a development perspective.
considering a production environment loaded with data. How does one apply changes to the model? You cannot regenerate the model and in most large organizations, database changes are executed by DBS's and not developers. In such situaitons, it is the role of the developer to develop delta-scripts that the dba can execute.
My experiense with Hibernate (Java) and the like is that you have to pay double when using such frameworks.
I have a webservice which of course has to be .net 3.5 (a side note is does anyone know why you can't create a webservice using .net 4.0?).
Anyhow it is using entity framework, which I have recently discovered was a really bad mistake to try to use this in .net 3.5.
I have a table "Licenses" with the following columns: LicenseKey, ProductCode, OrderID, Seq, UserName.
In my asp.net 4.0 application I can simply do the following to perform an update:
[Code]....
But it appears there is no ExecuteStoreCommand in .net 3.5 with entity framework. Can anyone explain to me how to accomplish the same thing? The thing I need to point out is that because this is a multi-user access service. I need to verify that SQL will only update the given record where OrderID and Seq is what I tell it ONLY if the UserName is already null. So if two users process the same statement at the same time only one would work and the other would not because the sql should fail (or return 0, rather than a 1) for the second one.
This is the sqlDateTime overflow problem again. Background. As I'm sure you know dates must be between 1/1/1753 and 12/31/2999. If you have an empty date field, it throws and exception. So I created a function (below) that solve the problem when attempting to update or insert a record with a date field. Works great.
Public Shared Function MakeDateField(ByVal pasDate As String) As Nullable(Of DateTime)
If IsDate(pasDate) Then Try If pasDate <= System.DateTime.MinValue Then Return Nothing Else Return CType(pasDate, DateTime) End If Catch ex As NullReferenceException Return Nothing End Try Else Return Nothing End If End Function
So I thought about using a time field. I have the field, have the validator in place and then attempted to test the page. It resulted in my least favorite error message "sqlDateTime overflow".
I can think of several workarounds like adding a date or a fixed date to the time field, or converting it to a string. Each of these is problematic.
IS THERE A BETTER WAY TO UPDATE/INSERT TIME FIELDS.
I need to do an update a field in database every x minutes. ie: a person login and I need to update a field related to they every X minutes until the value reach a value. Like this, this person start a count event from 1 to 10, they log off the web, but this count must remain countting until reachs 10, 1 by 1 every 7 minutes. I cannot do a SQL Job. Should I User a System.Timer??? Should I record the time and value of the last update, when the person log in I cauculate and update the value??
I have a table in my database with a one to many relationship to another table, which has a relationship to a third table:
[Code].....
This seems to work fine. My question to you good folks: Is there a correct way to do this? I tried following the making a custom model binder per the blog link I posted above but it didn't work (there was an issue with reflection, the code expected certain properties to exist) and I needed to get something going ASAP. PS - I tried to cleanup the code to hide specific information, so beware I may have hosed something up.
Is there a way to export a EF 4.0 Data Model to EF 3.5?
I looked around and found that we are not able to access EF 4.0 from a ASP.Net 3.5 project here: [URL]
Our project is the 1st to go to .Net 4.0 using Entity Framework and we (the team) were wondering if there was a way for the other projects that "might" need to access our data that are still using the .Net 3.5 framework.
I'm working on a new project where I have the luxury of working from a Model to Database approach using Entity Framework 4.
The project I'm working on is taking an agile approach where different phases will be rolled out over time.
Will the Model First approach work in my case? I noticed when you "Generate Database from Model" it recreates the entire schema from scratch which will obviously wipe all the data that is in the db. I was hoping for a more "Update Database from Model" approach where the db would just be altered to reflect the changes rather than recreated
