C# - Can LINQ To SQL Detect Where A Table Association Breaks
Jul 28, 2010
I have two tables I am using to fill a gridview. The tables have a common field named RangeActivityID. My problem is that the database is very old and some of the older entries do not match up IDs between tables, so I am unable to add an association between them in the database.
I do not care about the old data which doesn't match up, so in my .dbml file, I manually created an association in order to select good data from both tables. This is the LINQ query I have:
var collective = from p in rangeConnection.RangeActivities
orderby p.RangeActivityID
select new
{
TestName = p.TestName,
DateTime = p.ActivityDateTime,.......
I can set my grid datasource to 'collective' and everything works, but if I uncomment the three commented lines, the query returns no results because the tables have data that doesn't meet the association criteria. Is there a way to have the LINQ query ignore results that do not match up?
I inherited this autoextender control, and I like the way it's working. Except that when I submit my form any object that was in the list no longer comes up. For example, I type in b, and anyone in my database with the last name starting with b would appear in in a list to be selected. If I select someone, and then apply those changes back to the database, no one with the last name b will appear in the list again if I type in b.
I have a 1:M relationship between Contact and EmploymentHistory.I want to create a new association that is the current employment, which would be 1:1 so I can do Contact.CurrentEmployment.The EmploymentHistory table has a CurrentEmployment flag.Is there a way to do this in Entity Framework?
I have to find the best way to do this using LINQ. I need to summarize an amount in a iTransaction table by
Account (e.g. 12345) and add that amount to an same Account ( e.g12345) if it exists in a iAccount table . Here is the code which syntax checks ok and tested ok up to the .submitChanges statement (i.e. I stopped and didn't allow the submit.
Following is the LINQ code. (1) Is that a good way to do this. OR should I try the INTERCEPT.
(2) How is the best way to insert a new record/row in the iAccounts table if it DOES NOT exist in the iAccount Table.
I have 3 tables 1-Category, 2-AssignToCategory, 3-User
Fields in Category (Id, CategoryName)
Fields in AssignToCategory (Id, CategoryId, UserId) -->CategoryName,UserId as forigen key
Fields in User (Id, Fullname)
There is no association defined just used forigen keys.Impoted in EF. Now I want to create association.
1 - Right Click on User and Category for association and 1 to many created UNCHECKING FK checkbox as foriden keys already defined. Relation created than double clicked on relation to assign Principal and Dependent key (Principal (User,Category) and Dependent is AssignToCategory). All done.
Error Error 1 Error 113: Multiplicity is not valid in Role 'User' in relationship 'UserAssignedToCategory'. Because all the properties in the Dependent Role are nullable, multiplicity of the Principal Role must be '0..1'. c:userslordalidocumentsvisual studio 2010ProjectsCodingCodingModelsCoding.edmx 93 11 Coding
Same error for Category.How do i create association if its not defined on imported tables.
SIDE NOTE: If I removed forigen keys from AssignToCategory and created an association with FK check box clicked so EF put the forigen keys than everything is fine.
I have implemented the File Upload (upon reading Scott Hanselman's excellent post)I have multiple files associated with various questions on the form though, and would like to associate each saved file with an internal ID.
How can I do this? For example, if question # 3 has a file uploaded abc.pdf, how can I associated that file with ID #3?
is it possible to have a button defined outside a grid view and give it a command name of "select" and somehow attach it to the gridview, so the grid recieves a select command when clicked without writing code?
I have a Listview that is connected to an EntityDataSource. What I'm having trouble doing is showing fields of an association in the Item Template rather than just the id.
For example, what it currently shows:
Name: John Doe Race: 3
What I wish it would show
Name: John Doe Race: Caucasian
Some example code:
[Code]....
Obviously, I'm getting the number because Race_ID is an integer. What I'm less sure about is how to bind it or Eval it in some manner that will let me match that id to a name in the other table (which is associated). I've tried <%# Eval("Race.Name") %>' and a few other things to try to get a name rather than an ID but I always get either the id or nothing at all.
I,am trying to create a self association relation for an organization chart data tree in Entity Framework,after trying different ways for prevention of exceptions like 3007 and etc. I found that when I put my foreign key in my POCO near Parent and Items navigation properties its work.but I think this is not correct that we have both ParentID scalar property and Parent navigation property. review this and tell me is it correct or not.I'm using VS 2010 RC and ofcource .net framework 4.0 RC
i want add a record to my table(News) in the database School.
so i create a class for news table look like this:
public class News { private int _newsid; private string _datetoshow; private string _title; private string _description; private string _writtenby; public int NewsID { get { return this._newsid; } set { this._newsid = value; } } public string DateToShow.......
pop up is:
'system.Data.Linq.Table <New>' does not contain a definition for add and no extension method 'Add' accepting a first argument of type 'System.Data.linq.Table<New>' could be found (are you missing directive or an assembly reference?)
In my application i want to compare data of two users from database table using linq.
lets say i have ten columns in UserMaster table.
Now based on the comparision i want to display result.
Like is 10 out of 10 columns matches for those two users result will be 100,if 9 columns matches then result will be 90 and if 0 matches thn result will be 0.
There are multiple different type of name/value pairs. I want to specifically return the custfield value where custfield name is "INCIDENT", and the custfield value where custfield name is "NETWORK" all for the appropriate WORKORDERID
I've tried a few different ways and just can't grasp how the linq is supposed to go to get the results I want. I can get an incident value, or network value, but not both.
I have the proper association set up in the dbml so both of these work to get the single value:
var b = from i in edcwdv.WOCUSTFIELDs join p in edcwdv.WORKORDERs on i.WORKORDERID equalsp.WORKORDERID where i.CUSTFIELDNAME.Contains("INCIDENT") select new { i.CUSTFIELDNAME, i.CUSTFIELDVALUE, p.WORKORDERID }; var incident = from wo in edcwdv.WORKORDERs orderby wo.WORKORDERID where wo.WOCUSTFIELDs.CUSTFIELDNAME.Contains("INCIDENT") select new { wo.WORKORDERID, wo.WOCUSTFIELDs.CUSTFIELDVALUE}; So essentially i want to pull the value for each of the fields, INCIDENT and NETWORK
Using Visual Studio I've created a DBML file, and added a table to it from a local database. This created a data context called UserDataContext. In my ASPX page I can create an instance of the data context using:
UserDataContext db1 = new UserDataContext();
However when I try to query against the table I get to:
var query = from o in db1.
and from there I can't see the table.... the dbml shows the table has public access.
DBSearchDataContext db = new DBSearchDataContext(); object q = from b in db.Articles where b.Tags.Contains(val) | b.NewsTitle.Contains(val) | b.EnglishContent.Contains(val) select b;
I cannot exclude results where category = video or photos. H to exclude category where value is "videos" or "Photographs"
I have a table created on the fly. The table structure is dynamic.
This is the table structure generated by the end of year 2010
DealerCode, 201010, 201011, 201012
This is the table structure generated by the end of Jan 2011
DealerCode, 201011, 201012, 201101
What I need to do is selecting all data and then bind it into a gridview
To build a LINQ query, we need to drag the table into dbml file first. As we don't know how the table look like, can we add it in dynamically? Are there any other solutions?
I am writing a function in which i generate autocode in specific format i want to make this function generalize so that i send tablename and columnname parameter and function return the next code. I am using linq to sql with MVC e.g. i want to make table name and column name dyanamic
I have tables two tables, the "book" and the "author", a book can have many authors and vice versa, so there is an intermediate table called "book_author" with two columns as foreign key for those two primary keys
book_author book_id author_id
I'm trying to edit the book details and also its author using the entity date model, The controller class method
[Code]....
The HTML edit form
[Code]....
I can only update the book table, but not author that the book has or the book_author, I'm new to asp.net, I can't easily find a tutorial on this issue, I think the logic is to delete the author of the book first and then add the author for that book, but I don't know exactly about that linq and C# code. Can show me? I can only update the book table, but not author that the book has or the book_author, I'm new to asp.net, I can't easily find a tutorial on this issue, I think the logic is to delete the author of the book first and then add the author for that book, but I don't know exactly about that linq and C# code.
i am choosing a category from a DropDownList controll, and if want to add a new category at the same time i have a TextBoks for it, i have create a Model, BLL and DAL classes, my problem is:
in the DAL class i want to add a new row to Question, but i need to check first if the object.category exsist in the table Category, if it does i want to get the Cid for it if it dosen't exist i want to create a new raw then get the Cid, this is my code:
public string add(Faq inFaq) { using (var db = new DBClassDataContext()) { try { var se = from Category in db.Categorys where Category.category == inFaq.category select Category.Cid; if (se.Count() == 0 ).........
