I want to add following where clause to Linq query. How subquery like below using linq
WHERE (Restaurants.[IsActive] = 1)
AND exists
(
select 1 from APIKeys
where ApiKey = 'on35e5xbt3m4cbcef4e4448t6wssg11o'
and (KeyType = 1
and fk_RestaurantsID = [t2].[RestaurantsID]
or KeyType = 2
and fk_RestaurantGroupID = RG.RestaurantGroupsID
and [t1].[fk_RestaurantsID] in
(SELECT RestaurantsID
FROM Restaurants
WHERE RestaurantGroupsID = RG.RestaurantGroupsID))
)
AND (0 = (COALESCE([t0].[fk_MembersID],0)))
AND (1 = [t0].[fk_BookingStatusID])
AND ([t0].[Email] = 'nike.s#gmail.com')
AND (([t0].[Phone] = '9999999990') OR ([t0].[MobilePhone] = '9999999990'))
Use Any() to produce subquery which translated to EXISTS. E.g. with AdventureWorks database sample:
from p in Products
where p.FinishedGoodsFlag &&
SalesOrderDetails.Any(od => od.ProductID == p.ProductID)
select new { p.ProductID, p.Name }
Will produce following query to database:
SELECT [t0].[ProductID], [t0].[Name]
FROM [Production].[Product] AS [t0]
WHERE ([t0].[FinishedGoodsFlag] = 1) AND (EXISTS(
SELECT NULL AS [EMPTY]
FROM [Sales].[SalesOrderDetail] AS [t1]
WHERE [t1].[ProductID] = [t0].[ProductID]
))
Related
The following LINQ query isn't allowed when I use multiple where elements - it stops liking the 'into':
var query =
from ph in _db.PlayHits
join ua in _db.UserAgents on ph.UserAgentId equals ua.UserAgentId
where (ph.VideoId == 1 && ua.AgentString.Contains("test"))
into hits
select new
{
ResultCount = hits.Count()
};
Any idea why or how I amend this?
The equivilent sql I want is:
select count(*) as ResultCount
from Playhits ph
join UserAgents ua on ph.UserAgentId = ua.UserAgentId
where ph.VideoId = 1
and ua.AgentString like '%test%'
To my understanding, counting of the results can be done using the extension methond Count as follows.
var query =
from ph in _db.PlayHits
join ua in _db.UserAgents on ph.UserAgentId equals ua.UserAgentId
where (ph.VideoId == 1 && ua.AgentString.Contains("test"));
int Result = query.Count();
I am sql query us producing correct result, but when i'm doing the same in LINQ. Output is incorrect. Please let me know where my making mistake.
Following linq query that i created.
LINQ Query:
List<UserModel> Model = (from users in db.UserM
join ct in db.CustT on users.UserId equals ct.UserID into group1
from g1 in group1.DefaultIfEmpty()
join ti in db.TestIn on g1.TestId equals ti.TestID into group2
from g2 in group2.DefaultIfEmpty()
where (users.CustomerId==CustomerId) && (users.RoleId == 4) && (users.Status == 1)
group new
{
g2.TestInvitationID,
g2.TestID,
}
by new
{
users.FirstName,
users.CreatedOn,
users.Email,
users.UserId
} into group4
select new UserModel
{
Name = group4.Key.FirstName,
CreatedOn = group4.Key.CreatedOn,
EmailId = group4.Key.Email,
UserId = group4.Key.UserId,
NoOfTestTaken = group4.Select(x=>x.TestID).Distinct().Count(),
NoOfInvitationsSent = group4.Count(x => x.TestInvitationID != 0)
}).ToList();
SQL Query:
SELECT IsNull(COUNT(distinct TS.TestId),0) AS NoOfTests,
IsNull(COUNT(TS.TestInvitationID),0) AS NoOfInvitations,
UM.Email,
UM.UserId,
UM.FirstName,
UM.CreatedOn
FROM UserM as UM
left JOIN CustT AS CT
ON UM.UserId=CT.UserId
left JOIN TestIn AS TS
ON TS.TestId = CT.TestId
WHERE UM.CustomerId=41
AND UM.RoleId=4
and UM.[Status]=1
GROUP BY UM.UserId, UM.Email, UM.FirstName, UM.CreatedOn
Tables:
"UserM" - columns: UserId, Email, FirstName, CreatedOn
"CustT" - columns: TestId, UserId,
"TestIn" - columns: TestInvitationId, TestId
The difference between SQL COUNT(expr) and LINQ Count is that the former excludes NULL values, which produces a difference when used on right side of a left outer join with no matching records (SQL will produce 0 while LINQ 1). The closest LINQ equivalent is Count(expr != null).
So the direct translation of your SQL query would be like this (note that the generated SQL query could and most likely will be different):
(A side note: When converting SQL query to LINQ, it's good to use the same aliases to make it easier to see the mappings)
var query =
from um in db.UserMasters
join ct in db.CustTests on um.UserId equals ct.UserID
into ctGroup from ct in ctGroup.DefaultIfEmpty() // left outer join
join ts in db.TestInvitaions on ct.TestId equals ts.TestID
into tsGroup from ts in tsGroup.DefaultIfEmpty() // left outer join
where um.CustomerId == UserSession.CustomerId
&& um.RoleId == 4
&& um.Status == 1
group ts by new { um.UserId, um.Email, um.FirstName, um.CreatedOn } into g
select new UserModel
{
Name = g.Key.FirstName,
CreatedOn = g.Key.CreatedOn,
EmailId = g.Key.Email,
UserId = g.Key.UserId,
NoOfTestTaken = g.Where(ts => ts != null).Select(ts => ts.TestID).Distinct().Count(),
NoOfInvitationsSent = g.Count(ts => ts != null)
};
var result = query.ToList();
I suspect that the following row is the problem because is not the same like in your sql:
Linq:
NoOfInvitationsSent = group4.Count(x => x.TestInvitationID != 0)
SQL:
IsNull(COUNT(TS.TestInvitationID),0) AS NoOfInvitations
Due to counting items from a left join Linq should be instead:
NoOfInvitationsSent = group4.Where(i => i != null).Count()
To put it all together, with a bit of better formatting:
var model = (from users in db.UserMasters
join ct in db.CustTests on users.UserId equals ct.UserID into group1
from ct in group1.DefaultIfEmpty()
join ti in db.TestInvitaions on ct.TestId equals ti.TestID into group2
from ct in group2.DefaultIfEmpty()
where users.CustomerId == UserSession.CustomerId &&
users.RoleId == 4 &&
users.Status == 1
group new { ct.TestInvitationID, ct.TestID }
by new
{
users.FirstName,
users.CreatedOn,
users.Email,
users.UserId
} into grouping
select new UserModel
{
Name = grouping.Key.FirstName,
CreatedOn = grouping.Key.CreatedOn,
EmailId = grouping.Key.Email,
UserId = grouping.Key.UserId,
NoOfTestTaken = grouping.Where(i => i != null).Select(x => x.TestID).Distinct().Count(),
NoOfInvitationsSent = grouping.Where(i => i != null).Count()
}).ToList();
I always thought LINQ to SQL equivalent for an exists query is to use Any(). But i recently wrote a query in LINQ , which basically is trying to find if duplicate records exists in single table.
Anycontext.Contacts.Any(c => ((c.FirstName == contact.FirstName && c.LastName == contact.LastName && c.AddressLine1 == contact.AddressLine1 && c.Zip == contact.Zip)||
(!String.IsNullOrEmpty(contact.Email) && c.Email == contact.Email)))
matching criteria is simple to find contacts with same FirstName, LastName and AddressLine1 or same Email. This query times out in 30 sec(default), there are just 500K rows in this table.
Wherecontext.Contacts.Where(c => ((c.FirstName == contact.FirstName && c.LastName == contact.LastName && c.AddressLine1 == contact.AddressLine1 && c.Zip == contact.Zip)||
(!String.IsNullOrEmpty(contact.Email) && c.Email == contact.Email))).Count()>0
I was forced to use Where clause and then do count greater than 0 to find if any duplicate exists in the set. What i can not understand is, why LINQ to SQL on simple Any clause timing out.
Any explanation will be really great here.
EDIT
SQL From from LINQ Pad
ANY
SELECT
(CASE
WHEN EXISTS(
SELECT NULL AS [EMPTY]
FROM [Accounts].[Contacts] AS [t0]
WHERE ([t0].[CompanyID] = #p0) AND ((([t0].[FirstName] = #p1) AND ([t0].[LastName] = #p2) AND ([t0].[AddressLine1] = #p3) AND ([t0].[Zip] = #p4)) OR (([t0].[FirstName] = #p5) AND ([t0].[LastName] = #p6) AND (EXISTS(
SELECT NULL AS [EMPTY]
FROM [Accounts].[PhoneNumbers] AS [t1]
WHERE ([t1].[ContactNumber] = #p7) AND ([t1].[ContactID] = [t0].[ContactID])
))))
) THEN 1
ELSE 0
END) AS [value]
Where
SELECT [t0].[ContactID]
,[t0].[CompanyID]
,[t0].[CompanyTitle]
,[t0].[FirstName]
,[t0].[LastName]
,[t0].[AddressLine1]
,[t0].[AddressLine2]
,[t0].[City]
,[t0].[State]
,[t0].[Zip]
,[t0].[Email]
,[t0].[Salutation]
,[t0].[IsActive]
FROM [Accounts].[Contacts] AS [t0]
WHERE ([t0].[CompanyID] = #p0)
AND (
(
([t0].[FirstName] = #p1)
AND ([t0].[LastName] = #p2)
AND ([t0].[AddressLine1] = #p3)
AND ([t0].[Zip] = #p4)
)
OR (
([t0].[FirstName] = #p5)
AND ([t0].[LastName] = #p6)
AND (
EXISTS (
SELECT NULL AS [EMPTY]
FROM [Accounts].[PhoneNumbers] AS [t1]
WHERE ([t1].[ContactNumber] = #p7)
AND ([t1].[ContactID] = [t0].[ContactID])
)
)
)
)
Not completely sure if this is what you want, but you could compare, I'm guessing you wont run the test often, as it would be better to test for existence before you input the data to the DB.
If you want to find the duplicates then
var queryA = from a in db.someTable
select a.value;
foreach(var row in queryA){
Console.Write(queryA.Where(b => b == row).Count() > 1 ? row: "");
}
If you just want to test if it exist then.
var queryA = from a in db.someTable
select a.value;
var queryB = queryA;
queryB.Distinct();
Console.Write(queryB.Count() != queryA.Count() ? "Yes" : "No");
I am trying to select from multiple tables in an entity model. But there are two columns I would like to select and it's just not working out. The LINQ statement I have is:
var searchResult = from i in _imEntities.Issues
join dept in _imEntities.Departments
on i.Issued_to_dept equals dept.Dept_ID
where i.State == 1
select new {
i.ID_No,
i.Issue_Date,
Raised_By = dept.Dept_Name
.Where(i.Raised_by_Dept == dept.Dept_ID),
Issued_To = dept.Dept_Name
.Where(i.Issued_to_dept == dept.Dept_ID),
Details = i.Details
};
The column names are all correct, but I just can't get the dept_Names into the Raised_By and Issued_To fields. Is there another way to execute this?
Try this:
var query = from i in _imEntities.Issues
join dept_r in _imEntities.Departments
on i.Issued_to_dept equals dept_r.Dept_ID
join dept_i in _imEntities.Departments
on i.Issued_to_dept equals dept_i.Dept_ID
where i.State == 1
select new {
i.ID_No,
i.Issue_Date,
Raised_By = dept_r.Dept_Name,
Issued_To = dept_i.Dept_Name,
Details = i.Details
};
It's not clear what you are trying to achieve. But you definitely trying to apply where filter on single name string (also predicate syntax is not correct). Here is query which conditionally returns Dept_Name in Raised_By and Issued_To properties:
var query = from i in _imEntities.Issues
join dept in _imEntities.Departments
on i.Issued_to_dept equals dept.Dept_ID
where i.State == 1
select new {
i.ID_No,
i.Issue_Date,
Raised_By = (i.Raised_by_Dept == dept.Dept_ID) ? dept.Dept_Name : null,
Issued_To = (i.Issued_to_dept == dept.Dept_ID) ? dept.Dept_Name : null,
Details = i.Details
};
How can I migrate this stored procedure into LINQ
DECLARE #customerIDs TABLE (customerID INT)
DECLARE #c INT
if (#customerName != '')
BEGIN
INSERT INTO #customerIDs
select id from customer
where name like '%' + #customerName + '%'
SELECT #c = COUNT(*) FROM #customerIDs
END
else
SET #c = 0
-- Insert statements for procedure here
SELECT DISTINCT l.*, dbo.GetListOfBranches(l.id) as 'list_of_branches', dbo.GetTopLevelCustomer(cid.customerID) FROM [login] l
LEFT JOIN login_to_customer ltc ON ltc.login_id = l.id
LEFT JOIN #customerIDs cid ON cid.customerID = ltc.customer_id
WHERE
(#c = 0 OR ltc.customer_id = cid.customerID) AND
(l.surname LIKE '%' + ISNULL(#surname, l.surname) + '%') AND
(l.forename LIKE '%' + ISNULL(#forename, l.forename) + '%') AND
(user_type = ISNULL(#userType, user_type)) AND
(l.active = ISNULL(#active, l.active))
ORDER BY surname ASC
I have got this so far:
List<Int32> customerIds = new List<int>();
if (!String.IsNullOrEmpty(customerName))
{
CustomerDataContext custDataContext = new CustomerDataContext();
customerIds = (from a in custDataContext.Customers
where a.name.Contains(customerName)
select a.id).ToList<Int32>();
}
LoginDataContext dataContext = new LoginDataContext();
var query = (from t in dataContext.logins
join t2 in dataContext.login_to_customers on t.id equals t2.login_id into a
from subquery in a.DefaultIfEmpty()
select new { t, listOfBranches = dataContext.GetListOfBranches(t.id), topLevelCustomer = dataContext.GetTopLevelCustomer(t.id) });
I need would then do a
if (customerIds.Count() > 0)
{
query = query.Where(a => customerIds.Contains(a.t.customer_id))
}
but as I need to perform the distinct I cant have the customer_id column in the query. Is there a way to include the
LEFT JOIN #customerIDs cid ON cid.customerID = ltc.customer_id
WHERE
(#c = 0 OR ltc.customer_id = cid.customerID)
Within the LINQ?
Thanks,
Richard