DataSource Controls :: Using LINQ To Pull Out A Single Value From A Single Result Row Of A Join Query?
May 25, 2010
For context: First of all, I am new to LINQ, as I have been using SubSonic for quite some time now.
I have two tables, Users, and Affiliates. They both have a very typical schema. The FK that joins them is the UserId field, which is in the Affiliates table. I want to create a LINQ query that pulls the Username from the Users table using the AffiliateId value. The AffiliateId is a primary key of the Affiliates table.
I have tried to accomplish this using many variations of the following code:
[Code]....
In the above query, I expect to get a single row result set. However, I instead receive the entire table of results.
How can I make this work? I have yet to see an example or article out there to do what I am trying to do.
I'm trying to achieve an outer join in LINQ but I'm not getting my desired result.There are two relational tables between Fruit_Name and Fruit_Ripe.The Fruit_Ripe table has a boolean field (IsRipe) that I use in my condition.The condition let me show all fruits that is not yet rippen (false) or fruits that isn't inputted yet in Fruit_Ripe table.
Dim fruit_salad = From myFruit In _DataContext.Fruit_Name Group Join myRipeFruit In _DataContext.Fruit_Ripe On myFruit.fId Equals myRipeFruit.fId Into Group From fruitty In Group.Where(Function(d) Not d.isRipe =
i have a form that my i use to look up whether or not there is an email address in the database. i wrote a query with this basic structure:
select *
from table A, table B
where table A.email = "email" or table b = "email"
i though that would return all instances that the email occurred in either table. what i am getting back is a bunch of null or other unrelated records from table A with a matching email in table B. the thing is, these two tables primary key to join them. i thought i wouldnt need to do that though in this case.
here is the actually query i am using if it makes things more clear:
Table1 - user master table. table2 - transaction table. Now I want to write a single query which will give results like table 3. how to write single query.
I am developing asp.net mobile application. I am using XML as a database. I am querying on the XML to access the required elements & attributes by using LINQ to XML in .net. I have the follwing part in my XML file.
[code]....
The similar logic I need for the above defined XML part. In the above XML I want to write the LINQ to XML query which can access the NAME attribute of the 'VALVE' node (<VALVE NAME="PWV">), then it should access the text between 'DISPLAY-NODE' (<DISPLAY-NAME> Production Master Valve </DISPLAY-NAME>), & then it should access the all the attributes of the 'COMMAND' node dynamically ( <COMMANDS USE-TEMPLATE="TRUE" TEAMPLATE-NAME="ValveCommands.xml"></COMMANDS>). All these I want dynamically without explicitly specifying the name of the child node as well as name of their attributes ( similar to the way I written the above query ) Can we write such a code by using LINQ to XML ? It will be better if we can write code for above issue in a single logic ( similar to the way I written the above query ).
To write a join query with or condition. It means a query has two inner join, here it is possible to fetch the records, if one inner join is true and other is false. I got a record when only two join conditions are true.
I have this ListView that has a Drop Down List.Everything works fine (I think/hope) except that the drop down list are not showing its result correctly.This is the code.
Front-End [Code]....
The code behind consist of the page_load and the ItemDataBound [Code]....
I have a stored procedure that returns 3 tables within the single recordset it returns. If I set a SqlDataSource to get data from this procedure, it works, but it only returns the first table. I want to have a GridView display the data from the 2nd or 3rd table using a SqlDataSource, but I can't figure out how to specify a particular table.
While there are some posts discussing this out there, I can't get a definitive answer about whether or not this is even possible (?). In a worst-case scenario, I can create another SP that only returns the 3rd table - but that creates a little maintenance headache that I would prefer to avoid.
I am trying to return single string result through a stored procedure and Linq. This works fine when I test the stored procedure but it is not returning the value to the page. The value returned is always 0 which is the return value. This is the stored procedure:
ALTER PROCEDURE Login @CustomerName nvarchar(50), @Password nvarchar(50) output As Select @Password=Password From Customers Where Customers.CustomerName=@CustomerName
This is the vb ALTER PROCEDURE Login @CustomerName nvarchar(50), @Password nvarchar(50) output As Select @Password=Password From Customers Where Customers.CustomerName=@CustomerName is the code created by the designer
This is the designer function <FunctionAttribute(Name:="dbo.Login")> _ Public Function Login(<Parameter(Name:="CustomerName", DbType:="NVarChar(50)")> ByVal customerName
As String, <Parameter(Name:="Password", DbType:="NVarChar(50)")> ByRef password As String) As IntegerDim result As IExecuteResult = Me.ExecuteMethodCall(Me, CType(MethodInfo.GetCurrentMethod,MethodInfo), customerName, password) password = CType(result.GetParameterValue(1),String) End Function
I want to get data from Projects(which have CourseId) and related CourseName from Courses table.
I have written following code:
var projects = from n in db.Projects join c in db.Courses on n.CourseId equals c.ID orderby n.Name select new { Project = n, Course = c }; return View(projects.ToList());
and I get error:
The model item passed into the dictionary is of type 'System.Collections.Generic.List1[<>f__AnonymousType22[ProjectManager.Models.Project,ProjectManager.Models.Course]]', but this dictionary requires a model item of type 'System.Collections.Generic.IEnumerable`1[ProjectManager.Models.Project]'.
What I need to do in Controller and in View to display this data?
I'm having a problem with my Linq to XML query. I'm getting the result data I want, but it's nested so deep that there must be a better way.Here is my XML:
[Code]....
I'm trying to get a list (simple string[]) of all Item IDs where Category Names contains "Other".Here is my Linq:
[Code]....
[Code]....
Here is a snapshot of my result from Visual Studio:The results I want are there ("item100", "item400", "item500"), but buried so deeply in the results var.
i have two queries they are: query1: select CustID,NoOfChits from tblCust1 where [Group]='A' and CustID='a001' query2: select count(TKCustID) as Taken from tblAuctionGroup where [Group]='A' and TKCustID='a001'
Results of 1st query was: ---------- CustID NoOfChits a001 2
Results of 2nd query was: ---------- Taken 4
But i want to like below: -------------------------- CustID NoOfChits Taken a001 2 4
in the above queries, 1st query displayed two columns and 2nd query displayed one column. but i would like to append the both results in single table or single record, i mean all results should be in same row in same result.
i am trying to use predicatebuilder for a linq to sql query but i cant seem to get a join to another table. in my model, i have a table for applicants and another for job applications.. each applicant can have several job applications.
i expect in linq to sql to be able to do something like;
p.jobapptable.jobappdate where p is the applicant.
this isnt the case..i am trying to use predicatebuilder to search through applicants based on the job applications they have made? how`can i get linq to sql to show the foreign key relationships?
I have huge excel files that I have to open from web browser. It takes several minutes to load huge file. Is it possible to open a single worksheet (single tab) at a time from excel file that contains many worksheets? I have to do this using C# / asp.net MVC
I am trying something apart of my boundries, is there any way to disable a single intem in dropdownlist or stop the ddl change event for a single item.
I have two tables namely "CategoryMapping" and "PartnerCategory"...The partnercategory table has foreign key with categorymapping on CategoryID...
let us say categorymapping should be filed first then partnercategory should be filed based on the categories defined in categorymapping. For example my two tables have the following data: