Joining LINQ Query Results For Each Item Together?
Feb 3, 2011
In my application, I have a search query textbox (txtSearch) that works well with one-word queries with the following LINQ:[code]So how would I make the above query more generic (ie: able to handle any number of words in a query)?I should note that the object being queried is a List of strings pulled from an Access database. As it stands, this application only queries the database once and I'd like to keep it that way if possible.
I have a query that can be summarised in SQL as follows;
Select S.StockCode From StockToCheck As S
[Code]....
Where the S var is a list of strings. This gives the error 'S' is not declared and points to the S in the function call / join (GetPOSStock). So it does not seem possible to do this in Linq, can anyone confirm?
'check for empty return Dim count As Integer = (From s In myEntity.employee Where employeeID = myEmployeeIDVariable).Count 'If there is a record, then process
I have a VB .Net linq query that I want to return values from two tables. I currently have this: Dim query = (From c In db.Client _ Join u In db.Users _ On u.UserID Equals c.UserID _ Where (c.ClientID = 1) Select c, u).ToList query (System.Collections.Generic.List(Of )) returns several rows as expected each item containing a c and a u. How do I iterate through the queries collection?
I have the following LINQ-to-Entities query:[code]This will give me all the resident assignments for the current year/term. Then I have this LINQ-to-Entities query:[code]This will give me all the rooms. I want to iterate through the assignments and based on what room is assigned update the occupancy in reset_occupancy. I'm not 100% sure how to accomplish this. Here is my pseudo code of what I want to accomplish:[code]
We are doing a query against an in-memory collection of LINQ data objects. The wrinkle is that we are ordering by a column in a related table whose records have not necessarily been loaded yet (deferred loading:)
Dim oPkgProducts = _ From b In oBillPkg.BillProducts _ Where b.Successful.GetValueOrDefault(Common.X_INDETERMINATE) = _
I have a list of object with 3 properties (quantity, service, name)I want to have all names and services in my list (kinda cross join) and the grouped quantity of the row corresponding. Not clear i guess
Quantity Service Name 3 Srv2 Bob 4 Srv2 Paul 2 Srv1 Paul 1 Srv2 Nick
I want as output All the services and all the names and corresponding quantities (0 if none)
Srv1 Paul 2 Srv1 Bob 0 Srv1 Nick 0
[code]....
Here is what I got so far, but I dont even get the expected resultsAnd I am acutally certain there is a pretty easy way of achieving what i want...
Dim services = (From a In interventions Select New With {.Service = a.Service}).Distinct() Dim months = (From b In interventions Select New With {.Month = b.DateHeureIntervention.Month}).Distinct() 'Dim query = (From s In services _
I know that LINQ queries are deferred and only executed when the query is enumerated, but I'm having trouble figuring out exactly when that happens.Certainly in a For Each loop, the query would be enumerated.What's the rule of thumb to follow? I don't want to accidentally enumerate over my query twice if it's a huge result.
For example, does System.Linq.Enumerable.First enumerate over the whole query? I ask for performance reasons. I want to pass a LINQ result set to an ASP.NET MVC view, and I also want to pass the First element separately. Enumerating over the results twice would be painful.It would be great to turn on some kind of flag that alerts me each time a LINQ query is enumerated. That way I could catch scenarios when I accidentally enumerate twice.
how to take a query that returns a single row of data and load that data into textbox controls.I know about ExecuteScalar but it is only good for a single column of data from the query.
I'm having a hard time joining 2 datatables and have the joined datatable as result. First datatable (labels) holds data including a printerid. Second datatable (printers) holds printer references (id > unc). I would like to have as endresult (joined) a datatable with all data from the first datatable with the field (unc) of the second datatable. [Code]
I have to join two main tables, and I need to filter the results by elements in an ASP.NET web form. These filters are created on the fly so I have to use a lot of where extensions to filter the query. I want to execute the query with as optimized SQL as possible.
I am first doing a simple join between TW_Sites and TW_Investigators. Then there are two sub-tables that are involved. TW_InvestigatorToArea and TW_InvestigatorToDisease. While most of the where clauses are working fine, I have found a performance issue that won't be an issue right now, but will be an issue as the table gets bigger.
The arrays DiseaseCategories and DiseaseAreas would be the results of a CheckBoxList result.
Protected Sub LoadResults() 'Get Dictionary of Filters Dim FilterDictionary As OrderedDictionary = Session.Item("InvestigatorFilterDictionary") ' Initialize LinqToSql
Forgive my ignorance on this.I have this LINQ Query:Dim ngBikersDataContext As New CarBikeWalkDataContext
bikersList = (From c In ngBikersDataContext.Reg_Bikers _ Order By c.L_Name _ Select New Bikers() With { _ .BikerID = c.BikerID, _ .F_Name = c.F_Name, _
[Code]...
with the error "Overload resolution failed because no accesible 'Select' accepts this number of arguments." Over the "NEW" I get an error " ')'expected."
Ok i have a query i use to parse an xml file to get an id number of a movie that allows me to get more detailed information about that movie from a database.Now the problem is the id is returned correctly with xml files stored on my hard drive (c:\desktop\movies)but when i try and parse an xml file on an external drive it dont get a hit on the <id>1123</id> node.
query Function movieID(ByVal directory) 'Get the movie name
I've got some code to try and loop through LINQ results, but it doesn't seem to be working.
HERE'S THE CODE
Public Sub ProcessRequest(ByVal context As System.Web.HttpContext) Implements System.Web.IHttpHandler.ProcessRequest ''# the page contenttype is plain text'
I have setup an OleDbConnection and my query works just fine but the problem I am facing is that I want the entire query not just a certain row or column. I also would like to place this entire query into a blank excel spread sheet.[code]
Before LINQ I would have my main application return the results of a SQL query into a dataSet. I would then transfer the dataset as a parameter to the external dll. Now I am bringing through a LINQ to SQL query that is returned as an IQueryable(Of vClientTable) object. I want to be able to transfer that set of vClientTable results to my external dll in order for the dll to work with the data included in the results.
I am probably doing it all wrong as well as trying to do it all wrong, but would like some advice on what would be the best method to use.
DB Query Public Shared Function getClientData(ByVal clientID As Int32) As IQueryable(Of vClientTable) Try Dim r = From p In dbLINQ.vClientTable _
[Code]....
Obviously in the external dll it has no idea what an IQueryable(vClientData) object is and even if I create a dbml file and datacontext in my external project for the dll that includes the same class to the DB table/view it still says that the objects are different types.
Just when I was thinking that I had Linq To Xml sussed I'm faced with yet another error! I think if I was to understand the linq search process in general better I might have more success, so any good links regarding that are also welcome. To my problem however; using the code below:
I'm having trouble populating an object from an XML file. I've copied an example I've found almost exactly, with variable names changed, but I keep getting the "Enumeration yielded no results" exception.
Here is my code:
[code]...
Essentially, the XML query is supposed to return the title and the description for every Property which has an element called Language Code, which is equal to "en-us". I have a feeling that my problem lies in my XML code, but I've been stuck here for a long time now.
