Hi I have SQL Table where I am storing values like this:
Column Name: Registration_ID
180,1801,1803,18011,220
180,1801,
180,1801,1803
No I want to match exact Registration_ID and get records based on the Registration_ID. I have tried Contains but is not matching exact values.
Here is my query:
var Result=db.Entity_StudentRepository.Get(x =>
x.Registration_ID.Contains(Used_For_Id.ToString())).Select(x => x.Registration_ID).ToArray();
Could you please try the following query and let know if it works-
db.Entity_StudentRepository.AsEnumerable().Where(t=> Registration_ID.Split(',').Select(int.Parse).Contains(Used_For_Id));
Related
Select * from web_data where Title like "%Lawn%" || Title like "%silk%"......and so on.
Lawn, Silk etc are in List<web_data>. So i'm looking for a way to search those substrings in the Title column(discription property). One of them must be contained, then the row should be returned.
I've tried this
query = query
.Where(x => filter.FabricType.Any(f => x.discription.Contains(x.discription)))
.AsQueryable();
It's not working. That linq to sql code returns an error:
Local sequence cannot be used in LINQ to SQL implementations of query operators except the Contains operator.
any alternatives?
You can use Contains() or You can also use .StartsWith() or .EndsWith().
collListItem.Where(x => x.discription.Contains("Lawn") || x.discription.Contains("silk")).ToList();
I have Documents table and Signs table. Document record can be related with many records in Signs table.
Now, I want to get all records of Documents table when document ID appears in Signs table.
Here I get all documents:
var documents = (from c in context.documents select c);
Here I get all my signs and save into List:
var myDocuments = (from s in context.signs where s.UserId== id select s.ID).ToList();
This list contains collection on document ID.
And here, I'm trying to get all documents that exists in myDocuments list:
documents.Where(item => myDocuments.Contains(item.ID));
But, when I do .ToList() allways return all records (in database only exists one compatible record)
What is wrong in LinQ statement?
The problem is that this statement doesn't modify the contents of documents, it merely returns the results (which you're not doing anything with):
documents.Where(item => myDocuments.Contains(item.ID));
documents is still the full list.
Change this line to something like:
var matchingIDDocs = documents.Where(item => myDocuments.Contains(item.ID));
And then use matchingIDDocs in place of "documents" later in your code.
I need to write a query in such way that the array(collection) is contain only sub query objects.
Suppose we have the two tables as follows:
TableA:
objectId, name
TableB:
objectId, names[array of name: parse pointer collection]
Here is my code which I tried:
// sub query
var subQuery = new Parse.Query('TableA');
subQuery.doesNotExist('name');
// main query
var query = new Parse.Query('TableB');
query.exists("names");
//query.containsAll("names", subQuery); // this means names should contain all subQuery, so this is not use full for me.
query.matchesQuery("names", subQuery);
This code is running fine, but this is not working as I want and also not showing the any error.
It seems that you don't need a subquery per se, but rather to first query your list of names, and then use that in your main query. What you seem to be looking for is: containedIn( key, values ) , as in:
query.containedIn("name", namesFromFirstQuery)
Actually I want to get the full table but it should be based on Doc_Type==distinct
Means it should only pick the records from table that has unique Doc_Type. I have tried with following but it returns me a single column into tolist() but I want to get full table. How can I do it?
var data = DB.tblDocumentTypes.Select(m => m.Doc_Type).Distinct().ToList();
You can use GroupBy
var data = DB.tblDocumentTypes.GroupBy(m => m.Doc_Type).Select(x => x.First());
In the table ReservationWorkerPeriods there are records of all workers that are planned to work on a given period on any possible machine.
The additional table WorkerOnMachineOnConstructionSite contains columns workerId, MachineId and ConstructionSiteId.
From the table ReservationWorkerPeriods I would like to retrieve just workers who work on selected machine.
In order to retrieve just relevant records from WorkerOnMachineOnConstructionSite table I have written the following code:
var relevantWorkerOnMachineOnConstructionSite = (from cswm in currentConstructionSiteSchedule.ContrustionSiteWorkerOnMachine
where cswm.MachineId == machineId
select cswm).ToList();
workerOnMachineOnConstructionSite = relevantWorkerOnMachineOnConstructionSite as List<ContrustionSiteWorkerOnMachine>;
These records are also used in the application so I don't want to bypass the above code even if is possible to directly retrieve just workerPeriods for workers who work on selected machine. Anyway I haven't figured out how it is possible to retrieve the relevant workerPeriods once we know which userIDs are relevant.
I have tried the following code:
var userIDs = from w in workerOnMachineOnConstructionSite select new {w.WorkerId};
List<ReservationWorkerPeriods> workerPeriods = currentConstructionSiteSchedule.ReservationWorkerPeriods.ToList();
allocatedWorkers = workerPeriods.Where(wp => userIDs.Contains(wp.WorkerId));
but it seems to be incorrect and don't know how to fix it. Does anyone know what is the problem and how it is possible to retrieve just records which contain userIDs from the list?
Currently, you are constructing an anonymous object on the fly, with one property. You'll want to grab the id directly with (note the missing curly braces):
var userIDs = from w in workerOnMachineOnConstructionSite select w.WorkerId;
Also, in such cases, don't call ToList on it - the variable userIDs just contains the query, not the result. If you use that variable in a further query, the provider can translate it to a single sql query.