I am working on a website similar to nerddinner. Is it possible to perform similar join using Linq to entities what is done with linq to sql in nerddinner.I am posting the codes below.
public IQueryable<Dinner> FindByLocation(float latitude, float longitude) { var dinners = from dinner in FindUpcomingDinners() join i in db.NearestDinners(latitude, longitude)
I have the following LINQ query that does a left join:
var results = from v in ctx.dat_Visitor join sp in ctx.vwSP on v.lu_Mentor.ID equals sp.ID into sp2 select new {
[code]...
My problem is that this LINQ query times out on me. I even upped the default timeout from 15 seconds to 120 seconds and it still times out. dat_Visitor has no more than 10 records in it, but vwSP (which is a view) has somewhere around 100,000 records. I know for sure that the timeout has to do with when I attempt to actually return sp2 in the results. If I change my LINQ query to not return sp2 in the results, then it is quick. Without sp2 the query looks like such:
var results = from v in ctx.dat_Visitor join sp in ctx.vwSP on v.lu_Mentor.ID equals sp.ID into sp2 select new { Visitor = v.Name, Tot = sp2.Count() };
Lastly, I'm using the 3.5 framework, but I am having serious thoughts about upgrading the website to 4.0, since I could then use DefaultIfEmpty().
I have two DataSet were mention below DataSet1 & DataSet2. DataSet1 records are already in User Database table. I would like to insert the DataSet2 records to User table, Before going to insert the Dataset2, I am trying to check the duplicate records in DataSet2 Compare with DataSet1. How to identify the duplicate records in DataSet2 using LINQ. I want to Get the List of Duplicate record set. Or Return the True Or False. Note: In User table SiteId and UserName is Combinational primary key Records.
I trying to create a search mechanism for records in a EDM based on text entered on a text box in a web page.
For example, if I enter a partial name of a customer and/or state abrebiation for that customer on the Text Box (abc, TX)s, I want to search name and state fields in a Customer table in my database for matching customers.
I found a solution with the namespaceSystem.Linq.Dynamic, but for some reason it is not working. It does not expose the Search() method. Here is the code I am using to perform the search;
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:
I'm trying to build a linq2Entity/gridview function for a forum, that draws data from multible tables.The result should be: Get the latest 10 threads that user(xx) has replyed in, that is not disabled or has a subject that is not allowed.Include information on the last post, thread owner user, and last post user, in each thread. ere is my code... is returns the correct threads and some that should not be there.
I have faced the peculiar case in Sql server's Inner join. I have 2 tablesFor example:Table Name: A and B I have shown the below code.
Select * From A Inner Join B ON A.JobCode =B.JobLookupID
This select statement return 500000 records but both table did not have that much recordsI have shown the Records in every table:A=19396 and B= 25366 records.How it will return more then 5 lakh records in above select statemenet?. Please let me know if any one faced this issue earlier?
How to use Stored Procedures with Linq to Entities? I prefer an example with input and output The videos on asp.net only show how to do this with Linq to SQL.
SELECT * FROM MessageAlerts AS A LEFT OUTER JOIN Contacts AS C ON A.ContactId = C.Id LEFT OUTER JOIN Users AS U ON A.UserId = U.Id INNER JOIN Businesses AS B ON B.Id = C.BusinessId OR B.UserId = U.Id
how to do this : ON B.Id = C.BusinessId OR B.UserId = U.Id with linq in entity framework.
I want to check for duplicate records,if the record is already inserted then "record has already been inserted" should appear or else if its a new record then it should be inserted.. This function is inserting even if it exists and showing the error msg..
Sub CheckForDuplicateRec() Dim da As SqlDataAdapter Dim ds As New DataSet Dim dt As New DataTable cmd = New SqlCommand("Select * from Table3 where Name='" & txtname.Text & "' AND FName='" & txtfathersname.Text & "' AND MName='" & txtmothername.Text & "' AND Add1='" & txtadd.Text & "' AND Add2='" & txtadd2.Text & "' AND Add3='" & txtadd3.Text & "' AND City='" & txtcity.Text & "' AND State='" & ddlstates.SelectedValue & "' AND Pincode=" & txtpincode.Text & "", con) da = New SqlDataAdapter(cmd) da.Fill(ds) dt = ds.Tables("Table3") If dt.Rows.Count = 0 Then cmd = New SqlCommand("Insert into Table3 (Name,FName,MName,Add1,Add2,Add3,City,State,PinCode) values('" & txtname.Text & "','" & txtfathersname.Text & "','" & txtmothername.Text & "','" & txtadd.Text & "','" & txtadd2.Text & "','" & txtadd3.Text & "','" & txtcity.Text & "','" & ddlstates.SelectedValue & "','" & txtpincode.Text & "')", con) cmd.ExecuteNonQuery() Else lblError.Text = "Records already exists" End If End Sub
WHY are all the examples on this site linq to SQL? Did ms not themselves announce dropping support for l2SQL over a year ago? i really don't get it. Examples are great.. but really not helping me since i've gone ahead and listened to MS. And can someone at MS clarify what the position is for linq 2 SQL.. Is it supported? Recommended? What the hell.
I am trying to learn LINQ to entities, and am working out how to best structure my BLL layer. I have generated the entity model and have created a generic repository in my DAL that returns results as IList<T>. I initially created the BLL to also return
results as IList<T>:
public IList<DAL.Customer> SelectAll() { [code]...
Now I am working on the aspx page, and I can create an ObjectDataSource and configure it to use my BLL, but since I am returning IList, I can't sort since I am not using a DataView. I have seen some articles on the web for converting IList to DataView, but that seems like a lot of overhead for every query.My goal is to keep a clean separation between layers without making things overly complicated. I would like to know how others have done this, or maybe a link to a good tutorial that shows how to structure all three layers.
I was trying to find out how I can join more than 2 tables using the LINQ-to-SQL syntax. For instance, joining 2 tables in SQL:
SELECT * FROM Table1 AS T1 INNER JOIN Table2 AS T2 ON T1.Key=T2.Column1WHERE T2.Key='17';
can be expressed as:
var Result = from T1 in DbContext.Table1 join T2 in DbContext.Table2 on T1.Key equals T2.ForeignKey where T2.Key=17 select new { T1, T2 };
But how would I join 3 or more tables using LINQ? For example:
SELECT * FROM (Table1 AS T1 INNER JOIN Table2 AS T2 ON T1.Key=T2.Column1) INNER JOIN Table3 AS T3 ON T3.Key=T2.Column2 WHERE T2.Key='37';
I've been searching and experimenting and I cannot seem to find any informraiton on this. One example I found involves putting the result for the frist join into a temp object, and then performing the second join. I'm not sure performance-wise if that's the same as doing a 3-table join directly using a single SQL statement.
I have 9 tables i need data out of.. 8 of those tables will always just return 1 row of fields that i need. the 9th table can contain many records.. So what i need is a few fields out of each of the 8 tables and then ALL records from the 9th table.. so i know that because there will be multiple records in the 9th table returned, that the fields i pull from the other 8 tables will contain duplicate information and thats fine since i will be displaying the individual records from table 9 on their own page..So everything could be for the same vendor, except for the date in the 9th table that contains specific dates and details about each record returned.When i review the execution plan im getting an yellow exclamation icon on a nested inner join and has this message as the warning: No Join Predicate
Here is what i have, but is returning incorrectly, way to may records, seems to be stuck in a loop.. then below that, i have one that returns the correct number of records, but everything except one column is duplicate, all the TR columns should be unique in the values stored in them.. the rest should all be duplicates, just because its the same vendor, so all the other information will be generic information about that record.
[Code]....
This FROM and WHERE return the correct number of records, but the fields are all duplicated except the last column with is transaction_date, seems that the 3 TR fields are being populated with the first records data or something.. not sure.
I have a webform which users fill in and all fields are submitted to table. How do I check that the record doesn't already exist in the table before the data is submitted? And if the data does exist I'd like to display error message label.
I have a page which consists of a grid and add new button. When the user clicks add new button he gets several fields to be entered. So, when he clicks submit I usually write a query which checks if there is an entry already in the database. In this case, I succeeded. However, my task is to also show the records identical and let the user decide to proceed or not.SO, I am not sure of how to proceed with this one. So, can anyone just help me in giving an idea on how to proceed with this one?
IF NOT EXISTS (SELECT * FROM Programme WHERE Title = @Title) BEGIN SET @ErrorMsg =@Title + ' Already Exists' RAISERROR (@ErrorMsg,11,1) return END I am Using this code to avoid Duplicate records in Database. Which code I have to write in .aspx.cs Page To Show Error Message on .aspx Page..
