DataSource Controls :: One Linq Query With Two Db Connection?
May 31, 2010
I want to use from two db connection in one linq query
My sample is:
int a=1;
if(a==1)
DataClasses1DataContext1 db = new DataClasses1DataContext1();
else
DataClasses1DataContext2 db = new DataClasses1DataContext2();
var q =
from c
in db.F_Groups
select c;
In this code a=1 so db connection is DataClasses1DataContext1
I want if a=2 then db connection = DataClasses1DataContext2
but this code is error.
db connections is completely same but in two deferent class a db connection is sql and another is oracle
I am using LINQ to SQL files in my class libray since every LINQ to SQL sources file is a seprate file and i have to set database connection string in each class library. Now, i have total 7 class libraires in my project how connection string be passed from web.onfg to LINQ file, so that i don't need to manually change the connection string. lke we did in asp.net 2.0 using connection string property in class file library.
How could we pass the same in LINQ's designer file.
I am having problem in diffrentitate error between internet connection loss error and Other Error in query for example: duplicate record found.
Both the error fall into System.Data.SqlClient.SqlException category.
But the way to handle both this 2 error is different.For connection error , i need to bring user to connection loss page while for duplicate record found error, i need to show the user a pop up.
Unless i do a checking exactly on the error message , else i have no ways to differentiate connection loss error and any other error. Am i correct for this?
I'm getting the following error after uploading my site on live server:Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached.i'm using the following code:
public static IQueryable<Property> Properties(string name, string city, string state, int pageIndex, int pageSize, ref int total) { ServerDataContext server = new ServerDataContext(); total = server.Properties.Count(x => x.Name.StartsWith(name) && x.City.StartsWith(city) && x.State.Contains(state)); return server.Properties.Where(x => x.Name.StartsWith(name) && x.City.StartsWith(city) && x.State.Contains(state)).Skip(pageIndex * pageSize - pageSize).Take(pageSize); }
Im doing thing profile, zip code thing on my site. One table has a list of zipcodes and in the other is a profile and there they keep what zip code they entered. I already have the radius code but idk how to get a list of all the profiles in a radius.I'm going to store the zip codes that come back from the zip code table in a arraylist and put it in a session state so i don't have to keep getting the same thing over and over again. The problem is i don't know how to write the linq to sql query to take the arraylist of zip codes and look up all the users that have that as there set zip code in there profile.
So I'm trying to add a single item to a query I wrote. The query is then pass to the e.Result of a LinqDataSource_Selecting event. This datasource is being used by a dropdown list and label in a listview.
I am trying to add a "New" field to the end of the list.
Currently I have this working, but it seems like a really messy solution. First I make a class with the fields I need:
I need to know how to extract the result of the attempted LINQ query below and set it equal to the strFile variable.Everything Intellisensed OK here but ine 5 shows a syntax error at the parenthesis.
I'm having a problem with a Linq query where is executing the second half of an OrElse even though the first half evaluates to true.
[Code]....
When Manufacturer is null, I get a NullReferenceException. The "Manufacturer.Trim()" should never be executed, because the first half of the OrElse evaluates to true. Just to test it out, I also tried this:
[Code]....
This actually works fine... Manufacturer.Trim() is never executed, and I get no error. Why is the Trim() statement being executed in the first case? If Manufacturer is null, then it shouldn't be.
Need to figure out the correct way to do a simple SUM function in Linq, but also manipulate one of the feilds coming back by doing a Substring on it, here is the original SQL query:
As the title sugests, I am missing a (basic?) concept as I teach myself asp.net, linq, and C#. It has been awhile since I've done anything object oriented, so I don't know how much that is impacting this gap in my understanding. Anyhow, here is what I am trying to do. I have three SQL Server tables: PERSON, POSITION, AREA. There is a 1 to many relationship between PERSON and POSITION, and a 1 to 1 relationship between POSITION and AREA. Given the following code I verify who the person is who has logged into the browser:
[Code]....
I want to be able to return all of the AREAs the person is able to access, based on the position they currently hold. I am able to easily do this in a SQL Server query, and I am sure I can do this with a SQL stored procedure once I pass the EMPLOYEE_ID to the procedure. However, I would rather do this in the page_load event, and load the returned results into gridview1 for the viewer. The issue I am running into is in building the LINQ query. When I try to build it, I can only get access to two of the three tables, depending on which table I select with db. Is it possible to access all three tables in the same query?
I have the following LINQ query which works correctly:
[Code]....
The following query, however causes an error:
[Code]....
"Could not translate expression 'Table(t_f2f_event).Where(e => ((e.EVT_START_DATE > Invoke(value(System.Func`1[System.Nullable`1[System.DateTime]]))) && (e.EVT_START_DATE < Invoke(value(System.Func`1[System.Nullable`1[System.DateTime]])))))' into SQL and could not treat it as a local expression."
I have a problem here.In my database I store member status in 1 and 0, when it come to my gridview I need change 1 and 0 to active and inactive. My company is using Linq, so I must follow. I wrote in this style, I calling a changeToWord() function to change 1 and 0 to active and inactive.
var q=from a in db.members select new{ mem_name=a.name, status=ChangeToWords(a.status) }
It compiles with no error, but when I execute the page, it prompt out a error message to me.
I'm trying to find an easy way to view the query that has been generated as part of the LINQ to DataSet syntax in my application. I found Scott Gu's blog and his creation of the Linq to SQL Debug Visualizer but it doesn't appear to work for my application. I am using OracleClient if that is important.
My next step is to simply configure the Oracle Manager for the database to see the query but I can't believe there's not an easy way to view this generated query.
I tried to find a LINQ section on this forum, but couldn't, so I'll post this here since is deals with LINQ, C#, MVC, SQL Server, and well...just about everything.
Here's the details....My Application is an ASP .Net MVC 1.0 app, using C# 3.5, SQL Server 2005 Std, and LINQ to Entity.
In my View, I have numerous Html.CheckBox controls, they get passed to my Controller as a string collection via a JQuery Ajax call. The values of each checkbox are seperated by a comma(,). I then Split the string, to get the individual values. The overall purpose to to allow users to build a custom report with only the data elements they have checked the boxes for. Here is my controller:
[Code]....
The part that I am having a problem with is that I only want to Insert the data elements into my DB table for the ones that the user has selected the checkbox for. So, for example, I'd like to do something like this:
[Code]....
I don't know if there is a LINQ switch statement in which I can access outside variables and the columns of the table, or any thing like that.
I am trying to fill a gridview with the data from Product table selecting few columns . I am using 3 - tier architecture and in DAL getproduct(userid) I am writing the query but cannot figure out exactly how to get that working .. here is piece of method I wrote
