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.
how can i select a record from A table and insert into B table using linq?
View 2 RepliesI 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.
[Code]....
I declared a 3 X 3 Matrix
int[,] matrix=new int[3,3]
{
{1,2,3},
{4,5,6},
{11,34,56}
};
when i try to enumerate it like var diagonal = matrix.AsQueryable().Select(); I am unbale to convert it as enumerable collection.How to do that?
I am working on LINQ. I am calling a SQL Stored Procedure with 2-3 parameters it's working fine. When i am going to call Stored Procedure with 8 to 9 parameters the auto generated column is not comming automatically. So i am unable to use LINQ with Stored Procedure with multiple parameters.
View 4 RepliesI'm unable to fetch just one integer value using this LINQ-query. LINQ seems to return everything as IEnumerable but I don't want that. First query should return just one string value which is then used in another query. That one should return integer which is also return value for method:
public static long GetTableIdByTableName(string name)
{
var result = (from aTable in objScope.Extent<Table>()
where aTable.Name == name
select { aTable.Id });
return ???????????
}
I have a question about linq delete.
I have 2 table in database and they are joined.
First Table: UserID, UserName, UserSurname, UserPhone, CompanyId
Second Table: CompanyId, CompanyName
First Table I have many recods with related second table.
I want to delete one company in second record, But firtly I have to delete users (more than 1)
How can I delete it with using linq?
I have downloaded Visual Web Developer 2010 Express and am trying to use LINQ. In order to do that I have added a LINQ to SQL class to the web site and have dragged tables from the database view into the LINQ designer, which worked fine.But..When I add: using System.Data.Linq;to MainPage.xaml.cs, I receive an error:
Error 3 The type or namespace name 'Data' does not exist in the namespace 'System' (are you missing an assembly reference?)Even although I have references to System.Core, System.Data, System.Data.Linq in the website references.
For some unknown reason I suddenly am unable to create an object variable for a Linq Data Class. If I create a new project and try the process again with the same database everything works as advertized.The code I am using is Dim db As New RoggDataContext which gives me an error on the object variable "db": Overload resolution failed because no accessibility 'NEW' accepts this number of arguments.I have looked inside every file in the Web Project like the web config to check the connection string, gobal, and designer.vb looking for any errors whit no JOY. I also tried to create a new form and code behind with a button and received the same error.This is mind blowing because as I already stated, I can create a new Web Site and the problem goes away.
View 3 RepliesI have a database table called Animals which I drag on to my Linq to SQL DBML file.
This creates me a class called Animal.
I then create a class to extend it, like so:
public partial class Animal{
//my extra code here
}
But what I also want to do is have a class like this:
public class Zebra : Animal{
//even more extra code here
}
The trouble is I get an InvalidCastException from my repository, when I do this:
Animal a = dataContext.Animals.Where(c=>c.id.Equals(id)).SingleOrDefault();
return (Zebra)a;
I've stripped back my classes to the point where they're completely empty in an attempt to work why it doesn't work. To no avail.
This casting process did used to work in the non-LINQ-2-SQL project that I'm switching to MVC/LINQ.
I wanted to delete the record from data but I receive this error "Unable to cast object of type 'System.Data.Linq.DataQuery`1[training_eval.Course]' to type 'training_eval.Course'.
Dim eval_sure = From ev In db.Evaluates Where ev.course_id = indexcourse Select ev.course_id
Dim del_course = From c In db.Courses Where c.Course_id = indexcourse
db.Courses.DeleteOnSubmit(del_course)
db.SubmitChanges()
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?)
i use Default membership provider for my membership
i add a profile table for some more information from user and it related with UserId with aspnet_Users
to get data from my database i use Entity Data Model
now i want to write a Linq to get data from all 3 tables
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.
i dont want to write if else for somany time.
I am new to linq.
Tables:
WORKORDER and CUSTFIELD
Fields:
WORKORDER = WORKORDERID
CUSTFIELD = WORKORDERID, CUSTFIELDNAME, CUSTFIELDVALUE
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
how can i do a join in this query to another table
dynamic list = _db.Users.Where(m => m.vcr_UserName != "superadmin" ).OrderByDescending(m => m.int_UserId).ToPagedList(Cpage, defaultPageSize);
i must have a topagedList there
I M New to Linq, I M Searching articles using
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
[Code]....
I have several tables to load from depending on a string value using Linq to Sql I currently have
[Code]....
but of course that only gets the specific table DOffices if I wanted to grab tables at runtime what would be the best way to go about it?
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 ).........
I have a table of user ids that is huge.
I have an array of user ids that I want.
I have two tables that have a foreign user id key.
What is the best way to get this information performance wise?
Ideally in SQL the final result would be somewhat like this (null values if there is no user ID in one table but not the other):
userid table1value table2value
1 null 12
5 123 null
And if so is there an example in vb .net? I want to add a linq result to the cache and then allow a mvc post to search the cache for better performance...every way I implement it I receive an object not referenced error...
I'm confused, maybe I shouldn't be doing it this way but the mvc post will be checking up to 2000 records and it would seem best not to have it querying the database everytime.
I am working on an ASP.net page that also users ChartFX. I need to pull a row from a database table and then flip it so that all of the labels for the row are in a column and all of the data from the row is in a parallel column to the labels.
I would really like to do this using LINQ and then create a table in memory to store these values until I need to use them.